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Ethiopia Sanitary & Phytosanitary Standards and Livestock & Meat Marketing Program (SPS-LMM)

Texas Agricultural Experiment Station (TAES)/Texas A&M University

Feed resources and feeding management: A manual for feedlot operators and development workers

Adugna Tolera (PhD) SPS-LMM Program

September 2008 Addis Ababa

Feed resources and feeding management

The preparation and publication of this manual is made possible by the support of the American people through the United States Agency for International Development (USAID) under Cooperative Agreement No.663-A-00-05-00437-00. The contents are the sole responsibility of the Ethiopia SPS-LMM Program and do not necessarily reflect the views of USAID or the United States Government.


Feed resources and feeding management: A manual for feedlot operators and development workers

Adugna Tolera (PhD) SPS-LMM Program

September 2008 Addis Ababa


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Table of Contents

Page List of Tables ...........................................................................................................................III List of Figures ..........................................................................................................................IV List of Abbreviations and Acronyms........................................................................................V Acknowledgements..................................................................................................................VI 1. Introduction............................................................................................................................1 2. Challenges of meat and live animal export............................................................................1

2.1 Sustainability of livestock supply for export ..................................................................1 2.2. Feed supply and quality ..................................................................................................1 2.3. Consequences of poor nutrition ......................................................................................2

3. Commercial feedlots vs small scale fattening operations ......................................................2 4. Ration formulation and feeding system .................................................................................3

4.1. Best cost ration formulation............................................................................................4 4.2. Total mixed ration...........................................................................................................4

5. Potential feed resources for feedlots ......................................................................................6 5.1. Concentrate feeds............................................................................................................7

5.1.1. Agro-industrial by-products.....................................................................................7 5.1.1.1. Oilseed cakes ........................................................................................................7 5.1.1.2. Milling by-products.............................................................................................11 5.1.1.3. Occasional surplus grain or grain damaged during processing ........................13 5.1.1.4. Phalaris sp. (Asandabo) weed seed ....................................................................13 5.1.1.5. Whole cottonseed ................................................................................................14 5.1.1.6. Molasses..............................................................................................................15 5.1.1.7. Poultry Litter.......................................................................................................16 5.1.1.8. Brewery by-products ...........................................................................................16 5.1.1.9. Mineral and vitamin supplements .......................................................................16

5.2. Roughages.....................................................................................................................17 5.2.1 Hay .........................................................................................................................17 5.2.2. Cereal and pulse crop residues..............................................................................20 5.2.3. Sugar cane tops......................................................................................................22 5.2.4. Hulls .......................................................................................................................23 5.2.5. Natural pastures.....................................................................................................24 5.2.6. Cultivated forages and pastures ............................................................................24

5.3. Other feed resources .....................................................................................................28 5.3.1. Household and horticultural wastes ......................................................................28 5.3.2. Thinning and leaf stripping from maize and sorghum...........................................28 5.3.3. Sweet potato vines..................................................................................................29 5.3.4. Cassava foliage and meal ......................................................................................29 5.3.5. Banana and enset plants and by-products .............................................................30 5.3.6. Cactus pear ............................................................................................................32 5.3.7. Foliage and pods from naturally growing trees and shrubs .................................32

6. Feed planning.......................................................................................................................33 6.1. Long term planning...................................................................................................33 6.2. Short term planning...................................................................................................33

7. Water supply ........................................................................................................................33 8. Summary ..............................................................................................................................34 9. References............................................................................................................................34 Annex.......................................................................................................................................36


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List of Tables Table 1. Example of a total mixed ration for fattening Boran bulls ..........................................6 Table 2. Major nutrient contents of the total mixed ration ........................................................6 Table 3. Most common concentrate and roughage feeds used by commercial feedlots............6 Table 4. Chemical composition and in vitro dry matter digestibility of noug seed cake

extracted by mechanical (with and without pre-cooking) and solvent extraction methods .......................................................................................................................9

Table 5. Chemical composition and in vitro DM digestibility of cottonseed cake as influenced by extraction methods .............................................................................10

Table 6. Chemical composition and in vitro dry matter digestibility of mechanically extracted linseed cake with and without pre-cooking...............................................11

Table 7. Chemical composition of wheat bran, wheat middlings and rice bran.....................12 Table 8. Chemical composition and in vitro organic matter digestibility of Asandabo

(Phalaris sp.) weed seed collected from Bale Agricultural Development Enterprise farms .........................................................................................................................13

Table 9. Nutritive value of whole cottonseed ........................................................................15 Table 10. Nutritive value of brewery and distillery byproducts ..............................................16 Table 11. Mineral composition of different mineral soils found in Ethiopia ..........................17 Table 12. Nutritive value of some grass and legume hays ......................................................18 Table 13. Quality of natural pasture hay harvested at different times in Debre Libanos, central

highlands of Ethiopia ...............................................................................................18 Table 14. Nutritive value of some cereal and legume straws ..................................................21 Table 15. Nutritive value of cottonseed hull............................................................................23 Table 16. Nutritive value of average quality mixed natural pasture, Cenchirus ciliaris (Buffel

grass) and Cynodon dactylon (Bermuda grass) ........................................................24 Table 17. Nutritive value of some horticultural wastes (DM basis) ........................................28 Table 18. Comparison of nutritive value of cassava hay and alfalfa hay ................................30 Table 19. Nutritive value of different parts of the enset plant .................................................31


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List of Figures Figure 1. Noug Cake .................................................................................................................9 Figure 2. Cottonseed Cake......................................................................................................10 Figure 3. Wheat bran...............................................................................................................12 Figure 4. Wheat grain screening used as feed for feedlot cattle at Sinana Agricultural

Development .............................................................................................................13 Figure 5. Phalaris or asandabo weed grain being harvested for feed at Hunte farm of Bale

Agricultural Development Enterprise .......................................................................14 Figure 6. Molasses in a storage tank.......................................................................................15 Figure 7. Natural pasture hay harvested at late stage of maturity in Sululta, North of Addis

Ababa ........................................................................................................................19 Figure 8. Natural pasture hay stacked in loose form on a raised structure .............................19 Figure 9. Baled hay is convenient to handle and transport ....................................................20 Figure 10. Tef straw stored in stack.........................................................................................21 Figure 11. A number of heaps of bales of wheat straw stored for feeding feedlot cattle, Hunte

Farm, Bale Agricultural Development Enterprise .................................................22 Figure 12. Sugar cane tops for sale to urban and peri-urban livestock producers in Wondo

Washa, Awassa woreda .........................................................................................23 Figure 13. A farmer in Adami-Tullu Jiddo-Kombolcha district, with Leucaena leucocephala

in his backyard .......................................................................................................25 Figure 14. Pennisetum purpureum (Napier grass) ...................................................................26 Figure 15. Rhodes grass being cut for hay using a scythe (Hwassa).......................................27 Figure 16. Oats (Shashemene Woreda) ...................................................................................27 Figure 17. Vetch (Shashemene Woreda Nursery site).............................................................27 Figure 18. Enset .......................................................................................................................31


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List of Abbreviations and Acronyms ADF Acid detergent fiber Ca Calcium CP Crude protein DM Dry matter EIAR Ethiopian Institute of Agricultural Research ILRI International Livestock Research Institute IVDMD In vitro dry matter digestibility Kg kilo gram Mcal Mega calorie MJ Mega joule ME Metabolizable energy NDF Neutral detergent fiber NEg Net energy of gain NEm Net energy of maintenance OM Organic matter P Phosphorus SPS-LMM Ethiopia Sanitary and Phytosanitary Standards and Livestock

and Meat Marketing Program TDN Total digestible nutrients TMR Total mixed ration USA United States of America USAID United States Agency for International Development


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Acknowledgements The preparation of this manual was initiated by the Ethiopia Sanitary and Phytosanitary Standards and Livestock and Meat Marketing Program (SPS-LMM), which is implemented by Texas Agricultural Experiment Station (TAES) of Texas A&M University System and financially supported by the United States Agency for International Development (USAID). I am very grateful to Dr Hank Fitzhugh, Chief of Party of SPS-LMM Program, for his encouragement, insightful comments and guidance at all stages of preparation of the manual. I would also like to thank Ato Belachew Hurrissa, Deputy Chief of Party of SPS-LMM, for his support and constant follow up of the work. I thank Prof. David Hutcheson for his very valuable comments on the draft of the manual. I owe him a great deal for his insights on best cost ration formulation and feeding system. I am very grateful to Dr Salvador Fernandez-Rivera for his great ideas of collating available information on Ethiopian feed resources and make it available for users in easily usable form. While preparing this manual I have referred to various published and unpublished sources of information including research papers published, in journals or workshop proceedings, by scientists working in different agricultural research systems and universities as well as various M.Sc and PhD dissertations, particularly M.Sc. Theses from Haramaya and Hawassa Universities. However, the list would be too long to accommodate all in this small publication. Hence only very few references that were cited for very specific purposes were included in the reference list. While compiling the nutritive values of the various feeds, I have also used the Ethiopian Feed Resources Database; a web based feed resources database and information system developed at International Livestock Research Institute (ILRI) in collaboration with the Ethiopian Institute of Agricultural Research (EIAR) with financial support of USAID through SPS-LMM Program.


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1. Introduction

Ethiopia has a large livestock population and diverse agro-ecological zones suitable for livestock production and for growing diverse types of food and fodder crops. However, livestock production has mostly been subsistence oriented and characterized by very low reproductive and production performance. On the other hand, market oriented livestock production has been gradually emerging in recent years. The Government of Ethiopia is trying to increase the export of meat and live animals that can contribute to market-led economic growth and poverty reduction in the country. The USAID funded Sanitary & Phytosanitary Standards and Livestock & Meat Marketing (SPS-LMM) Program has been launched in support of these government efforts. The goal is to increase annual export of meat from Ethiopian cattle, sheep and goats by about three fold. One of the main constraints hampering the attainment of this goal is the supply of livestock which can meet export quality requirements. This is mainly influenced by the type of animals coming to the feedlots, animal health issues and availability and quality of feeds. 2. Challenges of meat and live animal export

2.1 Sustainability of livestock supply for export The sources of animal supply for fattening and export are mainly the pastoral areas and some smallholder mixed farming areas. These smallholder farmers and pastoralists usually keep a limited number of animals to fulfill their subsistence requirements. Until recently livestock production has not been market oriented. The production and reproductive performance of animals under these production systems is usually sub-optimal. The main feed resource base is natural pastures and crop residues. The use of purchased feeds and other inputs is very much limited or non-existent. Poor feeding and the resulting poor performance of animals in the smallholder livestock production system has an impact on supply of animals for feedlots on sustainable basis, future fattening performance of the animals and the yield and quality of meat produced from such animals.

2.2. Feed supply and quality Feed shortage is the main cause for the poor performance of the livestock sector in Ethiopia. Most livestock destined for export or slaughter are produced in the pastoral areas from rain fed pastures and are slaughtered with little or no access to better quality feeds required to increase weight, improve condition and dressing percentage and reduce age at slaughter. In pastoral areas, natural pastures are the main source of livestock feed. However, they cannot fulfill the nutritional requirements of the animals particularly during the dry season, due to poor management and their inherent low productivity and quality. Although the total livestock population is increasing, the livestock holding per household is decreasing from year to year due a gradual decrease in the area of grazing land caused mainly by increasing cultivation. Moreover, large areas of grazing land in the pastoral areas are becoming unsuitable for grazing due to bush encroachment. In the mixed farming areas both natural natures and crop residues make the main source of livestock feed. Fodder conservation for use during the dry season is not common in most parts of the country.


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2.3. Consequences of poor nutrition Poor nutrition is the major impediment to market oriented livestock production. It leads to slow growth rate in growing animals and low production and reproduction performance. Poorly fed animals give low output of meat and milk. Nutritional problems also lead to delayed age of onset of puberty, long parturition intervals, low conception rates and low overall lifetime reproductive performance. Under poor feeding conditions animals take too long to reach optimum slaughter weight and the meat produced by such animals may not satisfy the desired quality attributes (such as tenderness) to fulfill the demand of the consumers. When the quality of the fodder is low animals are not able to eat what is required to put on weight. Because of the slow growth rate, the animals become old before they reach the desired live weight for sale. Hence the quality of the beef becomes far from satisfactory. Feed utilization is very inefficient as most of the feed (about 85%) is used for body maintenance. In such a system there appears to be a tremendous potential for improvement. Proper feeding, health care and overall management of livestock is a pre-requisite for realizing the potential benefits of the huge livestock resources of the country. Available feed resources should be used more effectively and efficiently. There is a potential for enhancing livestock productivity by supplementary feeding using different agro-industrial by-products, horticultural crop wastes and occasional surplus grain. 3. Commercial feedlots vs small scale fattening operations Both large scale (commercial feedlots) and small scale fattening operations are carried out in Ethiopia. Commercial feedlots feed relatively large number of animals at a time. The commercial feedlots keep from as few as about 20-50 animals to as many as 5000 heads of cattle at a time. Almost all commercial feedlots depend on purchased concentrates and roughage feeds for their operation as they do not have land for feed production. Most feedlots are located in East Shewa zone of Oromia Regional State, particularly around Mojo, Adama, Wonji and Melkassa areas. This gives them easy access to agro-industrial byproducts such as wheat bran, oilseed cakes and molasses, which form a major portion of the concentrate mix fed to the animals. Purchased native grass hay from Sululta, north of Addis Ababa, and tef and wheat straws make up the roughage component of the diet. Another place where commercial feedlot operation is carried out is Bale Agricultural Development Enterprise. The major feed resources used on all farms of the Enterprise are crop by-products such as straw, grain screenings, low grade grain and weed seeds. Wheat and barley straws are abundant byproducts produced on all farms of the Enterprise and comprise a major proportion of the diet of the animals. Feeds purchased from outside include linseed cake and molasses and occasionally wheat bran, although on most farms, wheat bran has been replaced by a grass weed seed (Phalaris seed). A substantial amount of this seed is produced on Hunte farm as a residue during seed cleaning. On the other hand, there are traditional and indigenous systems of cattle and small ruminant fattening practices in different parts of the country. These are typically carried out in the backyard using any feed resources produced on the farm. The notable examples of backyard fattening practices are carried out in Wolayita and Hararge areas. Farmers in Wolayita have a long tradition of fattening oxen using locally available feeds. They feed one or two oxen for about 3-4 months and sell during festive holidays such as Meskel and Christmas. The main feed resources are crop residues, cut-and-carry grass and various agricultural byproducts such as sweet potato vines and tuber, thinning or whole crop maize, enset supplemented with boiled maize and haricot bean and household wastes such as atella and coffee residues.


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Similarly the fattening practice in East and West Harage zones of Oromiya Regional State is based on thinning and leaf stripping of maize and sorghum, grasses and weeds from crop lands and other agricultural byproducts such as sweet potato vines. Backyard fattening in Arsi Negelle area is based on areqe atella (a residue resulting from home distilling of an alcoholic liquor, areqe) and wheat straw supplemented with a small amount of wheat bran and linseed cake or any other oilseed cake. A similar practice of backyard fattening of one or two animals based on atella, crop residues and/or cut grass with occasional supplementation of wheat bran has also been observed in Selale, North Shewa zone of Oromia Regional State.

4. Ration formulation and feeding system Ration formulation is the process of combining an assortment of feed ingredients into a ration that will meet the nutrient requirements of animals for the intended purpose of production. A balanced ration is one that provides all the required nutrients in such proportions and amounts that will properly nourish a given animal for 24 hours. In addition, consideration must be given to the amount of dry matter that the animal is able to or will consume during the 24 hour period. The goal of any feeding program is to provide the correct amount and balance of nutrients to animals at proper time to achieve the desired level of performance and profitability. In order to formulate rations and predict performance of animals fed a given ration, it is necessary to predict intake, which is usually about 2-3% of body weight on DM basis. Rations are nutritionally balanced and formulated to meet the nutrient requirements of animals both for maintenance and production. In the case of feedlot animals, production refers to body weight gain and changes in body condition. Thus, feedlot animals require nutrients for maintenance and body weight gain. The ration must be balanced in such a way that it provides:

• sufficient quantity of energy yielding nutrients • sufficient quantity and adequate quality of proteins • sufficient quantity and correct balance of minerals • the necessary vitamins • sufficient bulk or roughage for normal rumen function

The energy requirements are expressed in terms of net energy of maintenance (NEm) or net energy of gain (NEg). The net energy system partitions the energy consumed into the energy needed to maintain body weight of the animal and energy used for body weight gain. The net energy of maintenance has a higher partial efficiency than the net energy of gain. The net energy of maintenance depends on the metabolic body weight of the animal and can be calculated as follows: NEm (Mcal/day) = 0.077*(Body weight, kg)0.75. The net energy system can also be used to calculate the amount of feed needed to meet an animal’s energy needs and formulate a ration to supply the needed energy per unit of dry matter. Protein is needed for muscle or lean tissue growth. As animals approach maturity both muscle development and protein requirement will decrease. Thus, protein requirement is higher in younger and growing animals than in older finishing animals. Beef cattle are ruminant animals that can utilize both roughages and concentrates. The roughage: concentrate ratio depends on the age of the animals and stage of feeding and decreases towards the final stage of the finishing operation. If a body weight gain of higher than 1 kg/day is desired, roughages should not make up more than 15-20% of the ration. In order to obtain higher level of body weight gain, high energy feeds such as maize should be fed in place of roughages. As the daily rate of gain increases, the net energy of gain increases while the net energy of maintenance remains the same.


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The feed ingredients used by most feedlots in Ethiopia (agro-industrial byproducts, hays or crop residues) are low in calcium. On the other hand, the agro-industrial byproducts contain more phosphorus than calcium, a condition that is very likely to cause calcium deficiency. Limestone is an excellent source of calcium and it can be included at the rate 1-1.75% of the ration to avoid the problem. Rations must be formulated and updated regularly to avoid underfeeding or overfeeding of nutrients. Underfeeding can cause impaired performance of animals whereas overfeeding would increase feed cost and decrease profitability. Proper ration formulation requires analysis of feeds that are highly variable from batch to batch such as forages and by-product feeds. Tabular values and previous analytical results may not be reliable for determining nutritive value of these feed ingredients.

4.1. Best cost ration formulation In formulating rations, components such as protein, energy, fiber, minerals and vitamins are usually considered. In addition to formulating a balanced ration for the animals, attention must also be given to meeting the nutrient requirement of the animals at best cost. Best cost ration formulation is based on the following three sets of information.

a) The nutrient requirements of the animals under consideration b) The nutritive value of feed ingredients to be included in the ration formula c) Cost of the feed ingredients

An Excel Program for calculating Best Cost Rations was introduced by Dr David Hutcheson, a senior feedlot consultant from Texas, USA. In this method, the best buy of commodities to be used in the ration formula are first determined taking into account their protein and energy contents as well as their price. The Program uses a simultaneous equation to solve for the overall values of each commodity under consideration in comparison with two reference commodities, one for protein and the other one for energy. A feed with the highest positive difference is a best buy feed. Then the ration must be balanced to meet the nutrient requirements of the animal. Nutrient requirements of animals are affected by the age and body weight of the animal, its growth rate, balance and interactions of components of the diet and nutrient availabilities. The ration must contain the right amounts of protein, energy (carbohydrates and fats), minerals and vitamins. Adequate supply of water must also be given due consideration for efficient utilization of the feed.

4.2. Total mixed ration What is total mixed ration? Total mixed ration (TMR) refers to a complete ration produced by blending all the feed ingredients, including roughages, concentrates as well as mineral and vitamin supplements. It is a ration that provides adequate nourishment to meet the nutrient requirements of animals. Because of complete mixing of all feed ingredients, each bite of feed consumed by an animal contains the same proportion of roughages and concentrates and the required level of nutrients (energy, protein, minerals and vitamins) needed by the animal. Feeding total mixed ration also creates a consistent rumen environment that helps improve feed utilization and productivity of animals.


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Advantages of using total mixed ration

a. Total mixed ration aids in eliminating animal selectivity of individual feeds. All forages, protein and energy supplements as well as minerals and vitamins are thoroughly mixed. If the roughages and concentrates are fed separately some animals may select the roughages only or consume only very little of the concentrate. Such animals cannot attain the desired level of body weight gain. On the other hand, some animals may selectively consume only the grain or concentrate and disregard the roughage. Such animals could suffer from stomach upset such as acidosis due to over consumption of grain and grain by-products and lack of structural carbohydrates in the diet. When total mixed ration is used, the animal has very little chance of sorting for individual feed ingredients.

b. Total mixed ration enables more accurate determination of dry matter (DM) and nutrient intake of animals. Completely mixed feeds, coupled with grouping of animals according to age and/or weight and feeding them to appetite allows greater flexibility in feeding exact amount of nutrients (energy, protein, minerals and vitamins) to more nearly nourish the animals according the desired level of performance (body weight gain).

c. When thoroughly mixed with the roughage component, concentrate mixtures can be liberally fed to feedlot animals resulting in more efficient use of feeds. It allows the animals to consume as close to their nutrient requirements for desired production, and at the same time maintains the physical structure or roughage characteristics required for optimum rumen function.

d. It allows overall better control of feed offered and consumed by animals and, thus, better control of feed costs.

e. It enables use of a wide variety of feedstuffs including less palatable ones.

Challenges of using total mixed ration To be an efficient and effective feeding program, the TMR has to be managed correctly. Critical management factors include the following.

a. There is a need for correct grouping of animals according age and body weight. b. The dry matter intake has to be closely monitored and there is a need for good feed

bunk management. Correct ration formulation and knowing the amount of DM consumed by the animals is very important to optimize productivity of the animals. Without good DM intake information, it is difficult to correctly formulate rations to meet the nutrient requirements of animals for body weight gain. Underfeeding of nutrients results in reduced performance of animals and overfeeding increases feed costs.

c. Thorough and consistent mixing of the ingredients is very important. A chopper is needed to cut (chop) the roughage feeds into small pieces to facilitate mixing with the concentrate.

d. Even after chopping, the roughages and molasses pose difficulty of mixing well with the concentrate mix. Thus, a special type of mixer (horizontal mixer) is required to mix the chopped roughages and molasses with the concentrate mix. In the absence of a horizontal mixer, the chopped roughage (hay or straw) and molasses could be manually mixed with the concentrate on a clean cemented floor using a shovel.


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Table 1. Example of a total mixed ration for fattening Boran bulls (Source: Hutcheson, 2007; unpublished)

Ingredient Percentage Maize grain 34 Wheat bran 23 Wheat middlings 15 Noug cake 10 Teff straw, chopped 8 Cane molasses 8 Limestone 1.75 Salt 0.25

Total 100 Table 2. Major nutrient contents of the total mixed ration

Nutrient Composition As fed DM basis Dry Matter (%) 92.4 100.0 NEm (Mcal/kg) 1.55 1.67 NEg (Mcal/kg) 0.97 1.05 Crude Protein (%) 12.6 13.7 Calcium (%) 0.87 0.94 Phosphorus (%) 0.70 0.75

5. Potential feed resources for feedlots As shown in section 2 above, most commercial feedlots depend on purchased concentrate and roughage feeds. The concentrate feeds are high in energy and/or protein. Accordingly they are classified as energy or protein sources or sources of both energy and protein. The roughage feeds are characterized by relatively higher fiber content and lower energy and protein contents than concentrates. Table 3 shows some of the most common concentrate and roughage feeds used by commercial feedlots. Table 3. Most common concentrate and roughage feeds used by commercial feedlots

Concentrates Energy Protein Energy & Protein

Roughages • Grain

(Maize, oats, barley, wheat, sorghum)

• Molasses

• Oilseed cakes – Noug cake – Cottonseed cake – Sesame cake – Peanut cake – Sunflower cake – Linseed cake

• Poultry litter • Brewers grain • Distillers grain

• Wheat bran • Wheat short • Wheat

middling • Rice bran • Whole cottonseed • Bean bran • Lentil bran

• Grass hay • Cereal & pulse

straws • Screenings (barley &

wheat) • Hulls (barley, beans,

lentils, beans, rice, cottonseed)


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5.1. Concentrate feeds

Concentrate feeds are characterized by high energy and/or protein contents. Concentrate feeds mostly include various agro-industrial byproducts and occasional surplus grains and grain byproducts. The most common concentrate feeds include the following.

• Milling by-products (wheat bran, wheat short, wheat middling, rice bran) • Oilseed cakes (noug cake, cottonseed cake, peanut cake, linseed cake, sesame cake,

sunflower cake etc.) • Molasses • Whole cottonseed and • Occasional surplus grain or grain damaged during processing.

Depending upon availability and price, modern finishing rations may contain about 75-95% concentrate and up to 90% of the energy may come from grain.

5.1.1. Agro-industrial by-products

Agro-industrial by-products are the by-products of the primary processing of crops, including bran and related by-products of flourmills, oilseed cakes from small and large-scale oil processing plants and by-products of the sugar factory such as molasses. These by-products are of relatively high quality feed. Agro-industrial by-products such as oilseed cakes and meals, wheat bran and molasses are important components of the concentrate feeds used in feedlots.

5.1.1.1. Oilseed cakes

Oilseed cakes are the residues or cakes that are produced as byproducts during extraction of oil from oilseeds. They include noug cake, cottonseed cake, groundnut cake, linseed cake, sesame cake, sunflower cake and others. Ethiopia grows most of the temperate and sub-tropical oilseed plants such as linseed, groundnuts, rapeseed, sesame, sunflower, cottonseed and noug or niger seed. Noug is native to Ethiopia.

• Processing of oilseeds could be carried out both at large scale and small-scale levels with variable degree of efficiency of extraction of the oil from the oilseeds. All oil processing plants, except Addis-Modjo Oil Factory, use the expeller (mechanical) method of extraction. The mechanical extraction employs the application of pressure to force out the oil from the oilseed whereas the solvent extraction uses organic solvent, usually hexane, to dissolve the oil from the oilseed.

• The oilseed cakes are rich in protein and serve as sources of protein in concentrate mixtures. The protein content may vary from 20-50% depending upon the type of oilseed and the method of extraction of oil (mechanical vs solvent). However, the protein content of most oilseed cakes (such as noug and linseed cake) lies within the range of 28-35%. Most oilseed cakes are low in the essential amino acids cystine and methionine and have variable and usually low lysine content.

• Depending upon the method of processing, some oilseed cakes may have high proportion fiber bound nitrogen, which could reduce digestibility of the protein. Such incidence is higher in oilseed cakes obtained from small scale press mills than from large scale press mills and solvent extraction (Mogus, 1992). The application of high temperature and pressure during extraction using the press method may denature the protein and reduce the nutritive value by reducing its digestibility.


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• Oilseed cakes can also supply considerable amount of energy, depending upon the method of extraction of oil and the amount of residual oil remaining in the cake. The energy content varies from 2.03 to 3.7 Mcal ME/kg DM depending on processing method. Net energy maintenance varies from 1.28 to 2.02 Mcal per kg DM and Net energy of gain varies from 0.71 to 1.36 Mcal per kg DM (see the Annex). Extraction of oil leaves a residue that may contain from nearly none to about 12% fat content depending upon the process and efficiency of extraction thereby contributing to the energy content of the diet. Solvent extraction removes nearly all the oil from oilseeds leaving only about 1% or less in the residue.

• Oilseed cakes produced by mechanical extraction of the oil from the seeds contain more fat and fiber and less protein than those produced by solvent (chemical) extraction. The high temperature and pressure of the expeller extraction may denature the protein in the oilseed cake and reduce its digestibility, particularly degradability in the rumen.

• The calcium content is usually low, which varies from 0.17 to 0.72% of DM whereas most oilseed cakes are high in phosphorus content (0.75-1.31). In general, oilseed cakes have high phosphorus, potassium and magnesium contents and low content of calcium and sodium (Mogus, 1992).

• In the case of cottonseed cake, there is a big variation in the protein and fiber content and digestibility of the cake depending upon whether the seeds were decorcoticated before extraction or not. The decortication of oilseeds before pressing for oil extraction removes the fiber contained on the seed coat and husks. Decortication removes the possible limitations that could be imposed by these components on feed intake and digestibility of the oilseed cakes. In cottonseed, decortication refers to removal of the residual lint and the seed coat.

• The different oilseed cakes differ very widely in their chemical composition. The crude protein (CP) content is higher in groundnut and decorticated cottonseed cake than in the other cakes. The lowest CP content is found in undecorticated cottonseed cake because of the dilution effect of the hulls on the other nutrients. The fiber (NDF and ADF) content is highest in undecorticated cottonseed cake followed by sunflower and noug cakes, which are not dehuled under Ethiopian condition, before extraction. Decorticated peanut cake has the lowest fiber content.

Noug seed cake – Noug seed cake (Figure 1) is one of the oilseed cakes commonly used as a protein supplement in the diet of farm animals in Ethiopia. Annually about 84,802.34 tons of noug seed are produced in Ethiopia and oil extraction is done almost entirely by mechanical press with predominantly old machines used in the milling industry (CSA, 2003). The amount of noug seed cake produced is about 50% of the noug seed processed. Hence the amount of noug seed cake produced per annum would be about 42, 401.17 tons. Most of the noug seed is produced in the western parts of the country, particularly western Oromia (West and South West Shewa, East Wallaga, Horro Guduru) and western Amhara (Gojjam and Gonder) regions. Most of the oil mills extracting oil from noug seed are principally located in these areas as well as in and around Addis Ababa.


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Figure 1. Noug Cake

The protein content of noug seed cake varies from 28 to 38% with most values lying between 30 and 35% (Table 4). The fat content varies from 2.1 to 12.6% with an average of 8.4% and an energy value of 2.37 Mcal ME/kg DM. It has high fiber (34.4% NDF and 8.4% lignin) content and relatively low digestibility (61.7% in vitro DM digestibility) compared to most other oilseed cakes. Noug seed cake can be highly lignified if the seed is not dehulled before extraction. Because of its high crude protein content, noug seed cake can be used a protein supplement in the diet of farm animals. When added to energy source feeds, it can improve feed intake, digestibility and animal performance. The crude protein and fat content of noug seed cake varies depending upon the method and efficiency of oil extraction from the noug seeds. Table 4.Chemical composition and in vitro dry matter digestibility of noug seed cake extracted by mechanical (with and without pre-cooking) and solvent extraction methods

Mechanical (press) extraction

Component Without precooking

With precooking

Solvent extraction

Ether extract (% DM) 12.2 (7.8-20.1)* 10.2 (6.0-16.5) 2.8

Crude protein (% DM) 31.4 (27.0-34.2) 30.9 (27.6-33.8) 33.4

Neutral detergent fiber (% DM) 36.7 (32.1-42.7) 35.9 (31.8-42.9) 32.7

Lignin (% DM) 13.3 (11.5-21.1) 12.4 (10.5-13.6) 14.6

In vitro DM digestibility (%) 61.8 (59.5-64.3) 62.8 (59.5-71.5) 58.8

*Values in the parenthesis are ranges

Cottonseed cake – It is a by-product obtained after extraction of oil from cottonseed using either of the two (mechanical and solvent) oil extraction methods. It has high protein content, usually more than 36% and the protein content of most cottonseed meals is usually around 40%. However, this may be lowered by addition of finely ground hulls. In general, it is an excellent protein supplement for ruminants. However, it is deficient in vitamin D, carotene and calcium, but rich in phosphorus. It may also contain a toxic substance known as gossypol, which could be harmful to very young animals that do not yet have a functional rumen. However, gossypol toxicity is not a problem for adult ruminants because of their ability to detoxify free gossypol in their rumen.

Cottonseed has a thick coat or husk, which is rich in fiber and of low digestibility. The presence of the husk lowers the nutritive value of the cottonseed cake. Thus the


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undecorticated cottonseed cake is suitable for the feeding of adult ruminants only. The husk can be completely or partially removed by the process of decortication, a process that involves cracking and riddling. Removal of the husk lowers the fiber content of the cake thereby improving the digestibility of the other nutrients. In general, the crude protein content of cottonseed cake may vary from 25 to 51% whereas the neutral detergent fiber (NDF) vary from 21 to 55% depending upon the extraction method and whether the seeds were decorticated or not before extraction (Table 5).

Table 5. Chemical composition and in vitro DM digestibility of cottonseed cake as influenced by extraction methods

Decorticated Undecorticated

Component (%) Press Solvent Press Solvent

Ether extract (% DM) 7.6 1.9 8.5 1.6

Crude protein (% DM) 44.5 51.1 25.0 26.6

Neutral detergent fiber (% DM) 23.5 21.1 48.9 55.2

Lignin (% DM) 4.6 4.8 10.7 11.0

In vitro DM digestibility (%) 77.8 78.6 56.7 53.2

ME (MJ/kg DM) 12.3 8.5

Figure 2. Cottonseed Cake Linseed cake – Linseed cake has a protein content of about 30% (Table 6). Linseed cake is one of the most popular protein supplements because of its high protein content and palatability. Moreover, linseed cake has a slight laxative effect, which helps to keep the animals healthy. It is unique among the oilseed cakes in that it contains about 3-10% mucilage. In general, it appears to have a conditioning effect on animals. Thus, it is useful for fattening animals as it can produce rapid gain and excellent finish. It gives the animals a shiny coat, though the body fat may be soft, and makes them more attractive to buyers on visual appraisal.


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Table 6. Chemical composition and in vitro dry matter digestibility of mechanically extracted linseed cake with and without pre-cooking

Without precooking With precooking

Component Mean Range Mean Range

Ether extract (% DM) 16.0 10.8-22.0 12.9 8.2-18.1

Crude protein (% DM) 29.1 24.1-30.5 28.2 26.0-31.6

Neutral detergent fiber (% DM) 34.1 26.0-41.1 31.6 26.8-39.1

Lignin (% DM) 7.1 5.6-12.4 8.4 6.7-9.6

In vitro DM digestibility (%) 70.5 61.6-72.1 72.1 71.5-72.6

Groundnut or peanut cake- Peanut cake is produced when oil is extracted from peanut, which is composed principally of the kernels with some portion of the hull. It has higher protein content (around 50%) than the other oilseed cakes. It is a palatable, high quality protein supplement, although, the protein is lower in methionine content compared to the other oilseed cakes. Peanut cake contains 2-7% oil and low fiber content. Storage of peanut cake under moist condition may result in the production of toxic products such afflatoxin produced by a species of fungus known as Aspergilus flaveus. Peanut is predominantly produced in Hararghe in the eastern part of the country. The main producer of peanut cake is the Hamaressa Edible Oil Factory near the town of Harar.

5.1.1.2. Milling by-products

Milling by-products include bran and related by-products of flour mills such as wheat short, wheat middling, rice bran and screening. These by-products are produced during milling of grain to produce flour for human consumption. Wheat bran is the most common milling by-product used for livestock feeding in Ethiopia. Wheat screenings are broken or shriveled kernels plus some foreign materials such as cheat and weeds. The various milling by-products are of great interest as livestock feed in commercial or market oriented livestock operations. The milling by-products, molasses and grain or damaged grain will predominantly serve as sources of energy. The milling by-products and grains are rich in starch and soluble carbohydrates whereas molasses is predominantly composed of readily fermentable soluble carbohydrates.

Wheat bran – Wheat grain consists of about 82% endosperm, 15% bran and 3% germ. Wheat bran (Figure 3) is the major milling by-product used as livestock feed in Ethiopia. It is the outer fibrous layer separated from the rest of the grain and germ. It is physically fibrous and flaky product. It is the outer kernel plus some flour with a protein content of 14-18% and ME content of 12 MJ/kg. The net energy maintenance of wheat bran is 1.63 Mcal per kg DM and net energy of gain is 1.03 Mcal per kg DM. It has high phosphorus (1%) but low calcium (0.1%) content. Wheat bran is quite palatable and is well known for its laxative characteristics because of its swelling and water holding capacity. This is due to its high fiber and non-starch carbohydrate content.

Wheat bran is one of the energy source concentrates containing easily digestible carbohydrates (α-linked polysaccharides). Such feeds are readily digested in the rumen with high energy yielding potential. Wheat bran also has a high protein content of about 17% (Table 7) and is a relatively good source of most of the water soluble vitamins except niacin. The crude protein in wheat bran has a relatively high digestibility of about 75%. The fiber and energy content of wheat bran may vary depending upon the quality of wheat being milled


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and the exact processing method used as these factors affect the overall blend of the bran components. When added to protein source feeds, wheat bran can improve feed intake, digestibility and growth performance of animals.

Figure 3. Wheat bran

Wheat middlings – Wheat middlings represent another byproduct of the wheat milling industry containing a higher proportion of germ and flour than wheat bran. Wheat middlings generally include screenings, bran, germ and flour remnants. They are common ingredient in feedlot rations and good sources of crude protein and supplemental energy. They have about 92% of the energy value of maize grain and contain more protein than maize. Wheat middlings contain nearly 40% NDF, which is highly digested in the rumen. They are very palatable and can be included in the ration mix at a level of about 15-25% of the total ration dry matter.

Rice bran – Rice production is a recent introduction to Ethiopia and it grows only in limited areas. About 86% of the rice is produced in Amhara Regional National State and the remaining 14% is produced in Oromia, Beneshangul-Gumuz and Gambella regions. In areas where rice is produced and processed for food, rice bran, rice hulls and broken rice grains are produced as by-products. Rice bran consists of the fibrous outer layer of the grain, some hulls and chipped grain. It may also include calcium carbonate, which is added during the milling process. In general, rice mill byproducts are characterized by high fiber and low energy content (Table 7). The bran is the most nutritious part of the rice crop. It has a protein content of about 9% and a fat content of 8%. Besides protein and oil, rice bran is an excellent source of vitamins B and E. The high oil content in rice bran increases its energy value. However, it may also cause rancidity under warm and humid climatic conditions thereby reducing palatability and increasing potential risk of toxicity. Table 7. Chemical composition of wheat bran, wheat middlings and rice bran

Components Wheat bran Wheat middlings Rice bran

Dry matter (%) 89.7 92.7 92.3

Ash (% DM) 6.6 5.0 17.7

Crude protein (% DM) 16.8 17.8 8.9

Neutral detergent fiber (% DM) 45.9 44.4 40.7

Lignin (% DM) 2.8 3.4 5.9

Calcium (% DM) 0.15 0.14 0.10

Phosphorus (% DM) 1.20 1.15 0.68


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5.1.1.3. Occasional surplus grain or grain damaged during processing

Grain damaged during processing and occasional surplus grain can be used as energy supplement. Substantial amount of screenings and damaged grains are produced during grain processing and seed cleaning. Grain represents a concentrated feed resource, which can be transported over a long distance with relatively less expense. Cereal grains (maize, wheat, barley, oats, sorghum and rice) are usually highly digestible (80-85%), rich in energy and have a protein content of about 8-12% of DM. Maize grain has a high potential in this respect because of its high energy content, relative abundance and reasonable price most of the time. Until very recently the price of maize grain used to be very close to the price of wheat bran. However, the extremely high price of maize observed recently is a unique phenomenon, which is a reflection of the global trend in food/feed prices. Cereal grains are low in calcium content and need to be supplemented with limestone to correct the deficiency. Excess consumption or rapid introduction of grain can cause sickness (bloating, acidosis) and even death of animals.

Figure 4. Wheat grain screening used as feed for feedlot cattle at Sinana Agricultural Development

Screenings of barley and wheat (Figure 4) have potentially high contribution to the diet of farm animals. Fourth grade barley screening has a crude protein content of about 12%, NDF and ADF contents of about 21.5 and 7.8%, respectively and in vitro organic matter digestibility of about 83%.

5.1.1.4. Phalaris sp. (Asandabo) weed seed

Phalaris species (Asandabo) weed seed has intermediate protein content, low fiber content and high in vitro organic matter digestibility (Table 8). Table 8. Chemical composition and in vitro organic matter digestibility of Asandabo (Phalaris sp.) weed seed collected from Bale Agricultural Development Enterprise farms Component Mean Range

Dry matter (%) 94.7 94.4-95.1

Ash (% DM) 5.8 3.2-9.1

Crude protein (% DM) 13.3 12.1-14.1

Neutral detergent fiber (% DM) 22.1 19.1-25.6

Acid detergent fiber (% DM) 8.6 6.1-10.7

In vitro OM digestibility (%) 79.5 77.7-81.0


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Figure 5. Phalaris or asandabo weed grain being harvested for feed at Hunte farm of Bale Agricultural Development Enterprise

5.1.1.5. Whole cottonseed

Whole cottonseed is of two types, namely white and black or de-linted cottonseed. White cottonseed is the seed remaining after the ginning process, which is also known as raw white or ‘fuzzy’ cottonseed because of remnants of lint on it. It is the preferred form whole cottonseed for animal feeding. Black cottonseed refers to whole cottonseed from which the lint has been removed. The de-linting is usually done for seed cotton production to be used for planting. Whole cottonseed can be used a source of both protein and energy because of its high protein and fat contents. It contains approximately 18-22% ether extract (crude fat) and about 20% crude protein on as fed basis (Table 9). Whole cottonseed can be fed alone or combined with other feedstuffs and it does not require any other processing or preparation before, although cracking of the seeds may enhance its rumen degradability in cattle. Where feed troughs are not available, whole cottonseed can be safely fed directly on the ground due to the large nature of the seeds. Molasses can be used as an attractant to increase palatability of whole cottonseed. Carbohydrates from roughages such as hays, straws and fodder trees are necessary in the diet when feeding whole cottonseed to avoid the possible scouring effect of its high fat content. The amount of whole cottonseed fed depends on:

• the potential risk from maximum chemical residue limits • amount of oil intake and its effect on the rumen • possible risk of gossypol toxicity (esp. if fed at >30% of the diet)

Whole cottonseed should not be fed to young calves of less than 4 months of age whose rumen has not yet developed and the amount fed to calves that are within the range of 5-12 months of age should not exceed 2 kg/head/day. In general, whole cottonseed should not exceed 2.5 kg/head/day for adult stock and should not be fed in the absence of a roughage source. Addition of limestone at the rate of 0.5-1.0% of whole cottonseed will assist the rumen to detoxify gossypol. The seeds should be stored in a dry and safe place to avoid mold development.


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Table 9. Nutritive value of whole cottonseed Component Value

Dry matter 90-93

Ether extract (% DM) 18-22

Crude protein (% DM) 20.5

Neutral detergent fiber (% DM) 48.9

Lignin (% DM) 12.2

Calcium (% DM) 0.15

Phosphorus (% DM) 0.75

Metabolizable energy (Mcal/kg DM) 3.11

Net energy of maintenance (Mcal/kg DM) 2.12

Net energy of gain (Mcal/kg DM) 1.45

5.1.1.6. Molasses

Molasses contains high levels of sugars which are readily digested in the rumen. It is also a good source of minerals such as calcium, potassium, sulphur and trace minerals but deficient in nitrogen and phosphorus. It can be a major or minor component of drought feed. It is a concentrated source of energy that can be stored for a long period of time. Since the protein content of molasses is negligible, it is usually fed with high quality protein or urea. Molasses is often used as a carrier for urea because it is palatable and provides a wide range of minerals.

Molasses urea mineral blocks or liquid licks or complete feed blocks are good sources of supplements depending upon proximity to availability of molasses. In areas accessible to sugar factory, molasses-urea mixture can be used in the form of liquid lick while the block is the preferred mode of use for areas not accessible to sugar factory. In areas that are far away from the sugar factories, transportation of liquid molasses may substantially increase the cost of using the molasses in the ration.

Figure 6. Molasses in a storage tank


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5.1.1.7. Poultry Litter

Poultry litter is a product that is obtained where poultry are raised on floor. It contains poultry droppings, bedding material and spilled poultry feed. It may contain about 15-35% CP depending upon the proportion and quality of the above constituents. It has high ash content with high levels of the minerals calcium, phosphorus, potassium, magnesium, sulphur and copper. It can serve as a good source of fermentable nitrogen and essential minerals. The calcium and phosphorus contents are around 2.1 and 1.8% of DM, respectively. The fiber content of poultry litter varies depending upon the type and amount of the bedding materials included in the litter.

5.1.1.8. Brewery by-products

The different breweries found in different parts of the country are producing substantial amount of brewery byproducts of potential feed use. However, these byproducts have not been fully utilized so far. In addition to commercial breweries, small scale home brewing and distilling is practiced in most localities and villages. Both categories of brewery and distillery byproducts constitute important sources of supplementary feed in commercial livestock operations. This is particularly important for farmers residing in the proximity of commercial breweries or for landless farmers maintaining a small number of fattening or dairy animals in urban and peri-urban areas. The byproducts have moderately high crude protein and metabolizable energy contents and digestibility (Table 10). Tella atella and areqe atella, by-products of home brewed and home distilled local alcoholic beverages, respectively, constitute the major ingredients of fattening rations in backyard small scale fattening operations practiced in some parts of the country such as Arsi-Negelle and Selale areas. Table 10. Nutritive value of brewery and distillery byproducts Component Brewers’ dried

grain Tella atella Areqe atella

Dry matter (%) 92.2 13.2 14.0

Organic matter (%DM) 95.8 95.7 96.2

Crude protein (%DM) 24.4 20.2 17.8

Ether extract (%DM) 3.9 7.8 NI*

Neutral detergent fiber (%DM) 55.1 52.8 37.0

Lignin (%DM) 4.7 9.7 5.1

In vitro DM digestibility (%DM) NI 66.1 78.8

Metabolizable energy (MJ/kg DM) 8.4 9.7 NI

*NI = No information

5.1.1.9. Mineral and vitamin supplements

If animals are fed in confinement for prolonged period of time, consideration must be given for provision of mineral and vitamin supplements. Animals that do not have access to green forages are likely to be affected by vitamin A and vitamin E deficiencies. Calcium is one of the minerals that is likely to be deficient in the ration of feedlot animals due to very low


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content of the mineral in most grains and agro-industrial by-products while phosphorus is relatively high. The imbalance in the Ca:P ratio is likely to cause calcium deficiency. Supplementation with small amount (about 1.5-2.0% of the ration) of limestone can alleviate the problem of calcium deficiency. It is desirable to include a small amount (about 0.25-0.50%) of salt to avoid the occurrence of sodium deficiency. There are also a number of mineral soils that can be obtained from different Rift Valley lakes and other areas containing adequate amount of most of the essential minerals with the exception of phosphorus (Table 11). Table 11. Mineral composition of different mineral soils found in Ethiopia Composition Bole (Lake

Abaya) Addo or Megadua

(L. Abaya)

Bole (Lake Abijata)

Bole (Lake Ziway)

Bole (Lake Shala)

Red Soil (Asela)

g/kg DM Calcium 34.1 8.0 7.2 3.5 17.0 2.0 Phosphorus 0.30 0.5 0.2 0.2 10.1 Potassium 7.80 11.9 8.2 5.9 7.3 10.3 Magnesium 4.70 5.5 16.0 0.2 15.0 19.0 Sodium 54.10 128.2 30.0 35 103.0 0.1 mg/kg DM Sulphur - - 530 30 230.0 910 Iron 807.4 473.4 510 600 650 1900 Manganese 451.6 483.9 83900 63500 47100 680000 Copper 11.5 6.2 600 15000 1300 32000 Zinc 53.2 30.0 3600 83000 62000 100000

5.2. Roughages

5.2.1 Hay

Fodder conservation in the form hay and silage is not a common practice in many parts of Ethiopia with the exception of the central highlands around Addis Ababa. There is along established practice of commercial hay production from natural pastures or meadow grass in parts of North and West Shewa zones of Oromia Regional National State. A more efficient system of harvesting grass using a scythe (locally known as falch) has been a common practice in these areas although in other parts of the country the sickle is the only tool available for cutting grass. Locally produced native hay can serve as useful source of roughage in feedlots and small scale fattening operations. However, the nutritive value of the hay could be very variable depending upon

• the botanical composition or species of the forage crop • the stage of maturity at the time of harvesting • harvesting, drying and storage conditions

Species of the forage crop - Some species of forage crops are more suitable for hay making than others. The most suitable species are those that have tall and leafy thin stems and erect growth form. Grasses such as Rhodes grass, Guinea grass and oats are among the cultivated grass species identified to be suitable for hay making. Among the forage legumes alfalfa, vetch, lablab and cowpea make good quality hay. Legume hays are superior to grass hays in their nutritive value. The fiber content is lower whereas the protein, energy and mineral contents are higher in legume hays than in grasses hays (Table 12). In the highland areas a mixture of oats and vetch can be used as very suitable crops for hay production.


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Table 12. Nutritive value of some grass and legume hays

Grass hays Legume hays Feed quality parameter Native

grass Rhodes grass

Oats hay

Alfalfa hay

Vetch hay

Cowpea hay

Lablab hay

Dry matter (%) 92.3 92.3 96 89.3 87.7 92 91.1 Organic matter (% DM) 90.3 90.2 92 88 89.3 90.4 87.5 Neutral detergent fiber (% DM) 73.2 72.9 74 42.6 50.7 42.3 41.2 Lignin (% DM) 7.5 5.9 8.0 7.2 11.4 7.7 6.5 Crude protein (%DM) 6.4 7. 8.8 19.2 19.1 14.4 18.2 In vitro DM digestibility (%) 57.2 58.6 58.8 66.3 65.8 68.5 66.6 Net energy for maintenance (Mcal/kg DM)

0.92 1.28 1.27 1.39 1.5 1.5 1.39

Net energy for gain (Mcal/kg DM) 0.23 0.7 0.70 0.81 0.91 0.9 0.81 Phosphorus (% DM) 0.01 0.32 - 0.23 - 0.34 0.32 Calcium (% DM) 0.24 0.44 - 1.6 - 1.08 1.51

Stage of maturity at the time of cutting – The stage of maturity at the time of harvest is one of the most important factors affecting forage quality. Forage quality is highest when the forage crops (grasses and legumes) are in the vegetative (immature) stage. The leaves are the most nutritious parts of forage crops. They have relatively higher protein and digestible carbohydrate and lower fiber contents and higher digestibility than the stems. As the age of the plant increases, the proportion of the leaves drops and nutrient concentration and intake potential of the forage declines. In general forage crops should be harvested for hay making immediately before or at the beginning of flowering. Most forage crops will have a 20% loss in total digestible nutrients and a 40% loss in protein by a delay of only 10 days past the most desirable stage of harvest. In general, late cutting of hay can cause a loss of about 20% in digestibility of the forage and shattering of leaves may cause a loss of about 20% of the nutritive value of the forage (Table 13). Table 13. Quality of natural pasture hay harvested at different times in Debre Libanos, central highlands of Ethiopia

Harvesting time Nutritive quality aspect October December Average DM yield (t/ha) 5.1 5.1 CP content (% DM) 9.6 5.8 Proportion of legumes (%) 11 5.8 Neutral detergent fiber (% DM) 61.8 66 Source: Suitte (2000) Harvesting and drying condition - The weather condition during the time of harvesting and drying of hay has a significant effect on the quality of hay produced. Bright sunny days with adequate solar radiation would be ideal for proper and rapid drying of hay. Rain that occurs during the harvesting and drying of hay causes both yield and quality losses that reduce the value of the hay as animal feed and a marketable commodity. Rain damage during hay making lowers the quality of the hay produced through the following mechanisms.

• Leaching: This is the movement of soluble nutrients out of the plant. Components of the plant that are very water-soluble are leached out of the forage and lost during rain. Most of these nutrients are the ones that are highly digested by animals. They include


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the readily digestible carbohydrates and soluble nitrogen, minerals and lipids. About of one half of the dry matter leached by rain is the soluble carbohydrates.

• Leaf shattering - Alternate exposure to rain and sun increases the incidence of leaf shattering. Forages that are rain damaged are more susceptible to leaf shattering after drying. Rainfall means additional raking and turning to speed up drying leading to more leaf loss.

• Mold growth: Rain damage can cause mold development leading to spoilage and loss of hay dry matter.

Figure 7. Natural pasture hay harvested at late stage of maturity in Sululta, North of Addis Ababa Storage Condition - The dried hay could be stored either as bales or in a loose form. Bales are easy to store and to transport. However, baling requires machinery or a baler to make bales. Alternatively a baling box can be used to make reasonable bales manually but may require more labor input. The moisture content of the hay should be reduced to below 20% before baling. If hay is baled at moisture content higher than 20% the bales could lose large amounts of dry matter caused by excessive heating and mold development. In extreme cases, spontaneous combustion may happen (the hay could catch fire). After proper drying the hay, be it loose or in a bale form, should be stored in a dry place preferably under a shade to protect it from exposure to rain and heavy sunlight. If the hay is stored outside as a haystack, the stack should be made with steeply sloping sides to prevent percolation of rain into the stack. It should also be stored on a raised structure (about 0.5 m from the ground) to prevent spoilage due to dampness and it should also be protected from termites and rodents (Figure 8).

Figure 8. Natural pasture hay stacked in loose form on a raised structure


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Figure 9. Baled hay is convenient to handle and transport If the hay is going to be transported over a long distance it is preferable to have it baled as loose hay is very bulky to transport. Baled hay is more convenient to handle and transport (Figure 9). Good practices in producing good quality hay from native pasture include maintaining high proportion of legumes in the pasture, harvesting at the beginning of blooming, ensuring high proportion of leaves, maintaining the green color and protecting from mold and foreign materials. Assessment of hay quality - The following are useful criteria for assessment of hay quality.

1. Color: Good quality hay should have a greenish color. If the hay is discolored (lost its green color) it is an indication of poor quality.

2. Leafiness: A high proportion of leaves in hay indicate well-managed and preserved hay.

3. Maturity: Good quality hay is made from forage crops harvested before flowering of the plant.

4. Odor: Good quality hay should have a desirable odor. 5. Foreign materials: Good quality hay should be free from undesirable weeds and

foreign materials. Weed control and management of the pasture field from which the hay crop is harvested is important to produce hay free from weeds and foreign materials.

6. Moulds and insect pests: Good quality hay should be free from mould and insect pests.

5.2.2. Cereal and pulse crop residues

Crop residues are becoming increasingly important as sources of roughage in feedlots. Major field crops produce large quantities of crop residues (straws, stovers and haulms) in addition to grain. These include cereal straws (e.g. tef, wheat, barley, maize, sorghum etc.), grain legume haulms (e.g. haricot beans, field peas, chickpeas, lentils, groundnut etc.). Sweet potato and cassava tops and vines, sugarcane tops and enset by-products are also becoming very important in small scale fattening. However, the principal crop residues used for animal feeding are the straws of cereals and pulses. The most important components of the crop residues are the leaves and stems that remain after the grain is harvested.


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Figure 10. Tef straw stored in stack (Photo by Adane Hirpa) The actual quantities of crop residues available for livestock feeding is reduced by the costs of collection, transport, storage and processing, seasonal availability, other alternative uses and wastage. Crop residues are not exclusively used for animal feeding. Some crop residues have alternative uses such as bedding material, construction purposes, maintenance of soil fertility, source of fuel, source of cash income and some may be wasted.

The nutritive value of crop residues is variable depending upon the species and variety of the crops, time of harvest, handling and storage conditions and other factors. Cereal straws and stovers are generally characterized by relatively low nutrient content, high fibre content, low digestibility and low voluntary intake (limited consumption) by animals. The nutrient supply of many cereal straws such as tef, barley and oat straws is closer to the nutrient supply of medium quality native grass hay. Thus good quality straw can be regarded as a good roughage source for feedlots next to native grass hay.

Most cereal straws and stovers have lower nutritive value than the haulm from grain legumes and/or vines from root crops such as sweet potato (Table 14). The haulms of pulse crops (grain legumes) represent good quality roughage with a crude protein content of 5-12%. Most roughage feeds (hays and straws) are bulky and of low nutrient density, which makes the transportation cost very expensive relative the nutritive value of the feeds especially when they are transported over a long distance. Thus, provision of such feeds should be designed in such a way that they come from easily accessible sources in an economical way. In general, as much as possible, all roughage feeds should be locally available and relatively inexpensive. If they have to be transported long distances they have to be dense and highly digestible to keep the price of the feed to a minimum.

Table 13. Nutritive value of some cereal and legume straws

Cereal straws/stovers Legume straws (haulms) Feed quality parameter Tef Barley Oat Maize Faba bean Lentil Peanut Dry matter (%) 91.9 93.4 92.2 91.0 91.5 92.4 91.1 Organic matter (% DM) 91.4 91.0 92.1 92.1 87.0 92.0 90.2 Neutral detergent fiber (% DM) 72.3 74.4 61.9 73.5 48.3 59.8 59.6 Lignin (% DM) 5.4 6.9 5.2 4.7 7.3 9.1 16.5 Crude protein (%DM) 4.8 4.4 5.7 4.0 10.2 7.7 11.4 In vitro DM digestibility (%) 53.2 50.4 57.9 56.1 65.1 54.3 69.1 Net energy for maintenance (Mcal/kg DM)

1.09 1.14 1.26 1.21 1.05 1.15 1.45

Net energy for gain (Mcal/kg DM) 0.53 0.58 0.69 0.65 0.5 0.59 0.86 Phosphorus (% DM) 0.31 0.14 0.18 0.1 0.14 0.21 0.1 Calcium (% DM) 1.18 0.36 0.25 0.31 0.89 0.73 0.59


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The crop residues are bulky and of low nutrient density. Thus, provision of such feeds should be designed in such a way that they come from easily accessible sources in an economical way.

Figure 11. A number of heaps of bales of wheat straw stored for feeding feedlot cattle, Hunte Farm, Bale Agricultural Development Enterprise

5.2.3. Sugar cane tops

Sugar cane tops can be used as a roughage source in feedlots operating in the proximity of sugar factories, around Wonji and Metahara. It can also be used in small scale fattening operations where limited amount of sugar cane is produced such as in Wondo Genet area in the south. Arrangements have to be made with the sugar cane plantations to make the cane tops accessible to feedlots in the area in a sustainable way. The sugar cane plant is approximately 50% water and of the dry matter 50% is sugar while the remainder is fiber. Although sugar cane tops is a potential feed for ruminants, transportation costs per unit energy would be very high because if its high water content. Thus, considering its bulky nature and the proportionally high cost of transportation relative to the feed cost per se, it would be more economical and logical to make use of the cane tops only in the proximity of the sugar cane plantations. Cane tops contain 25-30% DM, 4-6% CP, 35-40% CF, 8-10% total ash and <2% Ether extract with total digestible nutrients (TDN) content of about 50% and Net energy maintenance and Net energy of gain content of 0.97 and 0.42 Mcal per kg DM, respectively. Because of its low protein content supplementation of cane tops with urea or leguminous forages can augment and enhance its utilization. Supplementation with protein rich agricultural by-products such as cassava and sweet potato foliages also can improve the utilization of sugarcane tops as animal feed. This is particularly useful for small scale fattening operations where production of these different crops and the fattening activities are carried out in the same place. Phosphorus and sulphur are also considered to be deficient in cane tops, which might warrant appropriate supplementation of these minerals in cane tops based feeding systems. Protein and mineral supplementation becomes more important when cane tops are fed as the only roughage source for animals that receive no other supplements.


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Figure 12. Sugar cane tops for sale to urban and peri-urban livestock producers in Wondo Washa, Awassa woreda

5.2.4. Hulls

Hulls from cottonseed and different legume grains are used as components of ruminant diets. These are byproduct roughage feeds produced in the process of extraction of oil from cottonseed and during milling of the different pulses or grain legumes. Cottonseed hulls are very palatable, easy to mix in rations and provide excellent bulk. They are low in protein and energy but high in effective fiber (Table 15). Cottonseed hulls could constitute up to 30-35% of complete feeds or total mixed rations. They may be used as the only source of roughage, but are more commonly used with limited amount of other roughages such as hay and/or silage. Fuzzy cottonseed hulls are preferred over delinted cottonseed hulls. Because of inadequate supply and increasing price of wheat bran and oilseed cakes, hulls resulting from milling of different pulse grains such as faba bean, lentils, field peas and grass pea are becoming common components of concentrate mixes in most feedlots in Ethiopia. However, the hulls have high fiber and low protein contents. The digestibility and energy content is low compared to wheat bran and oilseed cakes. Hence, the hulls from different pulse grains cannot replace feeds such as wheat bran and cottonseed cakes in a concentrate mix. Table 14. Nutritive value of cottonseed hull Component (%) Cottonseed

hull Lentil hull

Faba bean hull

Field pea hull

Grass pea hull

Dry matter 88.5 87.9 89.7 89.3 90.2

Ether extract (% DM) 1.4 NI* NI NI NI

Crude protein (% DM) 4.1 16.0 9.2 8.0 11.0

Neutral detergent fiber (% DM) 89.8 49.4 69.0 66.3 71.5

Lignin (% DM) 19.3 NI NI NI NI

In vitro DM digestibility (%) 27.0 50.9 56.9 47.8 71.5

NEm (Mcal/kg DM) 0.75 0.99 0.62 1.54

NEg (Mcal/kg DM) 0.22 0.44 0.09 0.95

* NI = No information


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5.2.5. Natural pastures

Natural pastures are naturally occurring grasses, legumes, herbs, shrubs and tree foliage that are used as animal feed. The availability and quality of natural pastures vary with altitude, rainfall, soil type and cropping intensity. The level and distribution of available soil nutrients and water are the main limiting factors. The productivity of natural pasture in the Ethiopian highlands ranges from 1 to 2 ton DM ha-1 on freely drained and relatively infertile soils and it could vary from 4 to 6 ton DM ha-1 on seasonally waterlogged fertile areas (Mengistu, 1987). The quantity and quality of feed obtainable from natural pastures declines as the dry season progresses. The protein content and digestibility of most grass species decline rapidly with advancing physiological maturity of the plants and reaches very low levels during the dry season. Table 16 shows the nutritive value of an average quality natural pasture. The intensity of cropping determines the area available for grazing. Livestock grazing is the predominant form of land use in pastoral areas, which receive less than 600-700 mm annual rainfall. However, in the densely populated areas (e.g. Ethiopian highlands), the better soils are used for cropping and the slope of hills and the seasonally waterlogged areas are allocated for grazing. In some highland areas there are seasonally water logged extensive grassland plateaus that restrict pasture use. Natural pastures are decreasing from time to time and gradually disappearing due to rapidly increasing human population and expansion of cropland. Increasing urbanization and use of arable land for housing, recreation, floriculture and industrial development is displacing a significant amount of grazing land. In general, the contribution of natural pastures to the dietary needs of feedlot animals has nowadays become almost insignificant as most of the big feedlots engaged in fattening of animals for export are concentrated in or around the urban centers such as Adama, Wonji, Melkassa, Modjo and Bishoftu without access to grazing land. Table 16 Nutritive value of average quality mixed natural pasture, Cenchirus ciliaris (Buffel grass) and Cynodon dactylon (Bermuda grass) Feed quality parameter

Mixed natural pasture

Buffel grass

Bermuda grass

Dry matter (%) - 33.7 20.9 Organic matter (% DM) 91.0 85.9 90.2 Neutral detergent fiber (% DM) 66.3 66.9 78.8 Acid detergent fiber (% DM) 38.8 38 36.3 Acid detergent lignin (% DM) 4.7 5.2 4.5 Crude protein (%DM) 6.6 11.1 12.7 In vitro DM digestibility (%) 62 59.2 55.0 Net energy for maintenance (Mcal/kg DM) 1.34 1.21 1.14 Net energy for gain (Mcal/kg DM) 0.77 0.65 0.58 Phosphorus (% DM) 0.21 0.27 - Calcium (% DM) 0.55 0.26 -

5.2.6. Cultivated forages and pastures

Production of cultivated forage and pastures depends on availability of species that are adapted to the climatic, edaphic and biotic factors prevailing in the environment in which they are to be utilized. Suitability of a forage species to a given area is judged based on dry matter yield potential, persistence, adequate feed quality, compatibility with other species and ease of propagation and establishment. Cultivated forage and pasture crops are mainly important as cut-and-carry sources of feed and as a supplement to crop residues and natural pastures. The type of cultivated forage crop produced is variable from place to place


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depending upon the prevailing climatic and edaphic factors. The most common cultivated forage crops include grasses like elephant grass (Pennisetum purpureum), Rhodes grass (Chloris gayana), guinea grass (Panicum maximum) and oats (Avena sativa) in the highlands. Among the herbaceous legumes, the most common ones include desmodiums (Desmodium spp.), vetch (Vicia spp.), Lucerne (Medicago sativa), lablab (Lablab purpureus), cowpeas (Vigna unguiculata) while the most common fodder tree legumes include Leucaenas (Leucaena spp.), Sesbania (Sesbania spp.), Calliandra calthyrsus, Gliricidia sepium, pigeon pea (Cajanus cajan) and others. Tagasaste (Chamaecytisus palmensis) is important in the highlands.

Figure 13. A farmer in Adami-Tullu Jiddo-Kombolcha district, with Leucaena leucocephala in his backyard

Production of improved forages should focus on those species that have high biomass yield potential such as Napier grass (Pennisetum purpureum), Rhodes grass (Chloris gayana), Guinea grass (Panicum sp.) and Buffel grass (Cenchrus ciliaris). The leguminous forages are important as sources of nitrogen, fermentable organic matter and minerals in crop residues and poor quality natural based diets. Among the grass species Napier grass is known for its high biomass production. However, its productivity could vary from one area to another depending upon climatic conditions and fertility of the soil. Nitrogen fertilizer or manure application influences the DM yield and CP content of the grass. The grass can be harvested at frequent intervals for cut-and-carry green feeding. Napier grass – Napier grass (Pennisetum purpureum), which is also known as elephant grass, is adapted to many areas of Ethiopia. It performs well from sea level to 2000 m above sea level. It grows best in high rainfall (humid and sub-humid) areas but its deep root system allows it to survive in the dry seasons. The optimum temperature for its growth is between 25 and 400C. Napier grass has a considerable contribution as animal feed. It can be used in different forms including cut-and-carry green feeding, grazing and ensiling. It can also make good hay if cut at a young stage but becomes too coarse if cut late. It is recommended to cut or graze the grass at or below a height of 1 m. It has a very high yield potential both as a sole crop and in combination with different herbaceous and tree legumes. It is very compatible with legumes such Silver leaf and green leaf Desmodium and tree legumes such as Leucaena.


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Figure 14. Pennisetum purpureum (Napier grass) The importance of Napier grass Napier grass is one of the most promising and high yielding fodder, giving dry matter yields that surpass most tropical grasses.

• Annual dry matter yield varies between 10-40 t DM/ha with an average of 16 t DM/ha depending on soil fertility, climate and management factors. Water deficit depresses forage yield and has a negative effect on CP concentration. Relatively high temperature during the dry season also reduce digestibility.

• Napier grass tolerates frequent defoliation under good weather conditions. Hence it can be cut every 6-8 weeks giving up to 8 cuts in a year, depending on fertilizer application, rainfall amount and distribution.

• There are dwarf and tall varieties of Napier grass. The dwarf “Mott” variety grows to a maximum height of 1.5 m and it is leafy and non-flowering. The tall varieties resemble sugar cane in habit.

• It is propagated vegetatively and it is a robust perennial with vigorous root systems. • Napier grass can be planted as a sole crop or in combination with a number of

herbaceous legumes. Compatible species include Desmodium uncinatum (silver leaf desmodium), Desmodium intortum (green leaf desmodium), Vicia dasycarpa (giant vetch), Stylosanthes guianensis (stylo) , Macrotyloma axillare (axillaries) etc. Planting Napier grass with forage legumes increases in the DM yield and CP content of the forage.

• It can be used for grazing, cut-and-carry feeding of fresh grass or it can be conserved in the form of silage or hay. Hay making is feasible only when it is young and leafy. Once it becomes stemmy, the succulent stems limit the rate of drying and with excess drying the stem becomes hard and brittle and less palatable.

• Ensiling is a better alternative of conserving Napier grass since leaving the grass to mature will compromise its quality. The quality of silage obtained from Napier grass depends on:

o Quality of the fresh grass – it should be harvested at proper age o The ensiling process - minimize activities of plant enzymes and undesirable

epiphytic micro-organisms and encourage the dominance of lactic acid bacteria

o Use of additives – it is low in fermentable sugars and thus addition of energy sources such as molasses and bran can enhance the quality of the silage.

Rhodes grass - Rhodes grass is one of the cultivated grasses that is suitable for hay making. It grows under a wide range of soil conditions except very heavy and very acid soils. It is also known for being drought tolerant and it performs best where the amount of annual rainfall ranges between 750 and 1500 mm. It can be propagated easily by seeds and vegetatively with


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pieces of rooting stolons. Seedling growth and development is rapid and cut can be expected in six to eight weeks if there is adequate moisture. It is most productive in the first two to three cuts and needs to be heavily fertilizer to perform well afterwards. It is a perennial crop with a life span of 3 to 5 years. It has fine leaves and stems that are suitable for hay making. The CP content of Rhodes grass hay varies from 3 to 7%, depending upon stage of maturity and handling conditions.

Figure 15. Rhodes grass being cut for hay using a scythe (Hwassa) Oats – Oats is a tall, annual cereal, widely grown as a fodder in temperate and subtropical countries. In Ethiopia, it performs very well in the highland areas. It may be grown in pure stand or in mixtures with annual twinning legumes such as vetches. It is often mixed with vetches for hay or silage making. Mowing and hand cutting are easy and it is a suitable crop for hay making. Single cut types should be mown after flowering, whereas multi-cut types should be cut earlier to encourage new growth. Oats hay has CP content of about 7%.

Figure 16. Oats (Shashemene Woreda)

Figure 17. Vetch (Shashemene Woreda Nursery site)


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5.3. Other feed resources

Other potential feed resources include the following: • Household and horticultural wastes • Thinning and leaf stripping from maize and sorghum • Sweet potato vines and tuber • Cassava foliage and meal • Banana and enset plants and byproducts • Cactus • Foliage and pods from naturally growing trees and shrubs

These feed resources are more suitable for use in small scale or backyard fattening operations in the areas where the feeds are produced than in commercial feedlots because of the relatively small volume of each feed that can be produced at one particular place and/or the high moisture content of most of the feeds that makes it difficult to transport them over a long distance.

5.3.1. Household and horticultural wastes

Household wastes constitute important sources of supplementary feed. Reject fruit and vegetables could also be important sources of feed for small ruminants in areas where horticultural crops are grown and marketed (Table 17). Dropped coffee leaves could be a minor source of feed, whereas coffee pulp and hulls represent relatively underutilized feed resources in coffee growing areas. Table 15. Nutritive value of some horticultural wastes (DM basis) Component (%) Cabbage waste Orange peel Banana peel Dry matter (%) 14 28.1 10

Organic matter (%DM) 88 94.6 75

Crude protein (%DM) 14.4 5.8 8.3

Ether extract (%DM) -

Neutral detergent fiber (%DM) 27.2 19.9 38.4

Lignin (%DM) - -

In vitro DM digestibility (%DM) 80.4 82.6 72.9

5.3.2. Thinning and leaf stripping from maize and sorghum

In addition to the dry stover, which is obtained after grain harvest, maize and sorghum can also generate animal feed throughout the cropping cycle as thinning and leaf stripping.

• Usually farmers plant more than one seed per hill as a security against germination losses. The extra seedlings are eventually thinned out at weeding time and serve as useful sources of feed for animals.

• Leaf stripping is another method of obtaining forage for animals from maize and sorghum. Leaf stripping involves removing the bottom leaves from the plant sequentially over a period of time. Fresh maize leaves contain sufficient protein,


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macro-elements and energy to support body weight gains of about 100 g/day in lambs with an intake of 770 g/day and feed conversion efficiency of 8-10 (Oteino et al., 1992).

• Topping is the harvest of maize plant tops at silking stage. Although labor intensive, both leaf stripping and topping can produce better quality feed than harvesting dry stover without significantly affecting grain yield.

• When maize is harvested in green cob, green maize stover, which of much better quality than the dry stover, is used as for feeding animals.

• Maize plants that fail to set seed and all male lines from seed multiplication sites and state farms are harvested immediately after shedding pollen grains and used as green forage.

5.3.3. Sweet potato vines

Sweet potato vines have a lower carbohydrate but higher protein and fibre contents than the tuber. The principal nutritive value of the sweet potato vines is as a source of protein and vitamins. The dry matter yield of sweet potato vines can be as high as 4-6 tons/ha with a crude protein content of over 20% and digestibility of about 70%. Sweet potato vines have good palatability. Because of very high water content (83-88%), goats fed sweet potato vines do not require additional free water. In addition to the vines, damaged tubers that are unfit for human consumption can also be fed to farm animals. A combination of sweet potato vines with starch in the tuber and addition of moderate levels of urea can lead to high rate of live weight gain in beef animals and high profitability. In general, in densely populated and land scarce areas, sweet potato has a promising potential for use as animal feed because of its relatively short vegetative cycle and high yield potential with minimal horticultural practices. Sweet potato has a vegetative cycle of 4-5 months fitting into tight cropping systems. It also has wide adaptation to diverse altitudes and temperature conditions and competes better with weeds than other root and tuber crops (Scott, 1992).

5.3.4. Cassava foliage and meal

Cassava is a tuber crop widely grown in tropical and sub-tropical areas and recently introduced to southern Ethiopia. Cassava leaves and processing by-products and wastes are used as livestock feed in areas where the tuber is produced for human consumption. The tuber is rich in energy but poor in proteins, minerals and vitamins. Although the tuber is basically used as human food, it may also be used as a source of readily fermentable energy in farm animal rations. Fresh or dried cassava peels may also be fed to cattle, sheep and goats as a source of supplementary energy. Cassava peels make up 15% of the tuber (i.e. 85% is flesh). Considerable amounts of cassava leaves are produced as a by-product when the roots are harvested. Cassava leaves may be fed fresh or after wilting to avoid cyanide toxicity. Cassava foliage contains high protein (>20% of DM) and relatively low fibre contents. In addition to high protein content, cassava foliage is also known for its good amino acid profile in the protein. The amino acid, especially methionine, isoleucine, leucine and lycine content of cassava hay is higher than that of alfalfa hay (Wanapat, et al., 2000) (Table 18).


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Table 18. Comparison of nutritive value of cassava hay and alfalfa hay Parameter Cassava hay Alfalfa hay

Dry matter (%) 93.4 90.0

Ash (%DM) 6.6 9.1

Crude protein (%DM) 24.9 17.0

Neutral detergent fiber (%DM) 34.4 46.0

Acid detergent fiber (%DM) 27.0 35.0

Acid detergent lignin (%DM) 3.8 9.0

The intake and digestibility of the fresh foliage is low probably due to the presence of condensed tannins. Harvesting the foliage at early growth stage of about 3 months and making hay reduces the condensed tannin and hydrocyanic acid contents and improve the nutritive value of the foliage. Sun drying of whole cassava forage crop to produce hay is a very effective mechanism of reducing the hydrocyanic acid content. Thus, the foliage can be used as the only protein supplement in cattle diet based on cereal crop residues and poor quality pastures. Cassava can grow in environments that are not suitable for other crops. It can also be managed as a high yielding, protein rich, perennial forage crop, with repeated harvesting of the foliage. This process can continue for 2 to 3 years if the nutrients exported in the leaves are recycled as fertilizer. Thus, cassava can be managed to maximize the production of carbohydrates (in the form of roots) or protein (by harvesting the leaves). For root production the growth cycle is from 6 to 12 months at the end of which the entire plant is harvested. When maximum protein production is the aim, the foliage can be harvested at 2-3 months interval by cutting the stems at 50-60 cm above the ground thereby encouraging the plant to re-grow. In this case, the root acts as a food reserve to facilitate the re-growth of the aerial part. Dual-purpose production systems are also possible whereby one or two harvests of the leaves are taken before the plant is allowed the normal development of the roots.

5.3.5. Banana and enset plants and by-products

Banana is a fruit crop mostly found in the humid and subhumid tropics as human food. It has a considerable potential for use as food and feed crop as it produces starch-rich fruits for human consumption and leaves, pseudo-stems and peelings that could be used as important sources of animal feed. The leaves have high protein content (about 15%) while the pseudo-stem is rich in fermentable energy. Banana leaves and pseudo-stems can be used as supplementary feeds to pasture and crop residue based diets. The banana plant has a high yield of total biomass. The residual biomass (leaves and pseudo-stem) yield could be as high as 13 to 20 tons of DM/ha in a year (Ffoulkes et al., 1978). The fully expanded lower leaves of the banana plant can be harvested and fed to animals almost throughout the year without adverse effects on its fruit production.


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Banana leaves and pseudo-stems have relatively high digestibility of 65% and 75%, respectively. However, both are deficient in fermentable nitrogen. Thus, they should be supplemented with a source of nitrogen such as urea and highly digestible forage or sweet potato foliage. Intake of large amount of water in fresh pseudo-stem may decrease the capacity of the animal to raise its DM intake. The low CP content of the pseudo-stem is another factor contributing to its low DM intake. On the other hand the difference in DM intake could partly explain the differences in DM digestibility between the leaf and the pseudo-stem of the banana plant. Higher DM intake with increased proportion of leaf implies that the rumen retention time would be lower, which would lead to lower apparent digestibility. Enset is a large banana like perennial plant (Figure 18). It is native to the highlands of south and southwestern Ethiopia. It is cultivated mainly for a starchy human food as well as livestock feed. The pseudo-stem, corm and the stalk of inflorescence constitute the most important components used for human food, whereas all parts of the plant can be fed to livestock. Leaf pruning and thinned enset plants are used for feeding animals.

Figure 18. Enset The very low DM content of the pseudo-stem poses DM intake limitation on animals while it could be an advantage if drinking water is in short supply (Fekadu and Ledin, 1997). The relatively high CP content of the leaf (about 17%) makes it a favorable feed resource in ruminant feeding as the protein content is comparable to that of many browse species (Table 19). The CP content of the pseudo-stem is usually less than 7%. Thus, unless properly supplemented with nitrogen sources, the low protein content could depress the feed intake and utilization of the corm and pseudo-stem when fed to ruminant animals (Nurfeta, 2008). Table 19. Nutritive value of different parts of the enset plant Component Whole enset Pseudostem Corm Enset leaf Dry matter (%) 10.0 14.4 20.2 12.4 Organic matter (%DM) 88.1 91.9 94.1 84.8 Crude protein (%DM) 6.7 3.6 3.0 17.5 Neutral detergent fiber (%DM) 50.1 62.0 48.8 59.6 Lignin (%DM) 5.1 10.3 6.8 1.4 Calcium (%DM) 0.55 0.42 0.16 1.12 Phosphorus (%DM) 0.29 0.41 0.24 0.39 In vitro DM digestibility (%) 69.2 Metabolizable energy (MJ/kg DM) 12.7 13.9 9.0


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5.3.6. Cactus pear

Cactus (Opuntia ficus-indica) pear is a drought tolerant plant adapted to arid and semi-arid areas. It is a very valuable feed resource for feeding animals particularly during drought or prolonged dry season. It is tolerant to poor soil conditions and produces high biomass yield with acceptable palatability to animals. However, it is low in nutritive value due to imbalance of nutrients or presence of some anti-nutritional factors. It is generally characterized by low dry mater, crude protein, phosphorus and cell-wall carbohydrate contents, but highly digestible and rich in structural carbohydrates and calcium contents (Tegegne, 2001; Gebremariam et al., 2006). It can remain succulent during drought or long dry seasons and produce forages and fruit as well as be a source of ample water for animals. It has much higher efficiency of converting water to dry matter than any grass species and is estimated to produce at least 10 ton DM/ha/year. It is characterized by low crude protein and fiber contents and high content of ash and non-structural carbohydrates (Degu et al., 2008). The low crude protein content is the main limiting factor of its use in animal feeding, which could be alleviated by small supplementation of high protein feeds such as oilseed cakes.

5.3.7. Foliage and pods from naturally growing trees and shrubs

\Use of herbaceous or tree legumes as supplements is also possible but wider use is constrained by limited availability especially during prolonged dry season or drought. Foliage of trees such as different Acacia species and Balanites aegyptica as well as the pods and fruits of Prosopis and different Acacia species can be used as a substitute for concentrate supplement. In general, the supplements are expected to play a catalytic role in feed utilization and are needed in small quantities relative to the basal roughage. Thus, they may be of relatively higher price and could be transported over longer distances.

Foliage from trees and shrubs contributes a significant proportion of feed to ruminants in rural areas. Farmers and pastoralists traditionally lop branches of trees and use them as supplementary feed for their animals during the dry season. The leaves and pods of trees and shrubs are sources of good quality feed during the dry season when herbaceous forages are in short supply. Foliage from trees and shrubs is the preferred forage particularly for goats. In harsh and arid conditions, trees provide more edible biomass than pasture and the biomass remains green and high in protein when pastures dry off and senesce. Trees can tap water and nutrients deep in the soil profile because of their deep-rooted nature. The leaves and pods from fodder trees and shrubs usually have higher crude protein and lower fiber content than dry grass forages and cereal crop residues.

Thus, proper and strategic use of these feed resources as supplementary feed during the dry season can help to minimize seasonal fluctuation in productivity. However, the gradual decrease in the number of browse trees and shrubs and inadequate management systems to optimize utilization of the existing trees and shrubs appears to be a problem in this regard. Thus, efforts should be made to protect the desirable tree and shrub species from destruction and make them available to animals either by trimming or lopping leaves and branches and beating down fruits or pods.


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6. Feed planning

To achieve optimal performance from feedlot operations, fattening animals should be fed adequate amounts of the right combinations of feeds during their stay in the feedlot. The supply a diet that is not properly balanced leads to inefficient utilization of feed. This requires both long term and short term planning of feed supply.

6.1. Long term planning

This involves planning of the total number of animals to be handled in the feedlot during the whole year and the total feed requirement for all the animals. This can be regarded as a master plan for the feedlot and the following items should be taken into considerations.

• The amount and qualities of feeds produced on the farm (pasture, hay, silage, crop residues etc.) if the feedlot has a possibility of producing some feed on its premises.

• Desired duration of feeding period for each group and expected level of weight gain • Feed requirements of different groups or batches of animals during the year based

on average feeding plans. • Optimal number of animals that can be fed at a time in the feedlot under the

prevailing conditions • Requirements of supplementary feeds (concentrates, minerals, hays, straws etc.) that

have to be bought from outside.

6.2. Short term planning

This is mainly concerned with the follow up and implementation of the long term plans and includes the following components.

• Grouping of animals according to weight, batch and performance level • Making feeding lists for different groups of animals • Making sure that the feeds needed are available (by ordering them in time) • In cases of shortage of feed, try to find alternative solutions

7. Water supply Water is the most important nutrient in animal feeding and animal health. It is the most abundant ingredient of the animal body in all phases of growth and development. A calf’s body contains 75-80% water at birth and about 55-65% water at maturity. Water has a number of vital functions in the body of animals including the following.

• It is a medium in which all chemical reactions in the body take place. • It is an ideal lubricant to transport feed • It aids in excretion of waste products from the body • It regulates body temperature • It is a buffering agent to regulate the pH of body fluids

The sources of water supply for animals include the drinking water, water available in the feed and metabolic water obtained from oxidation of fat and protein in the body. The water consumed by drinking and the amount of water available in the feed consumed constitute the water intake of animals.


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Restriction of water intake lowers feed intake, nitrogen retention and loss of nitrogen in the feces. On the other hand, it increases excretion of urea in the urine. Cattle that are gaining weight require more water than those that are losing weight. Animals may lose nearly all the fat and about one-half of the protein of the body and survive, but loss of about one-tenth of the water of the body could lead to death. Thus animals need continuous supply of water for maximum efficiency. The water intake of animals is influenced by many factors such as breed and body size of the animal, ambient temperature, water temperature, humidity, feed supply and water content of the feed, salt and performance level. 8. Summary Feeding cattle for export quality, involves feeding high energy rations. The higher energy rations will promote finishing the cattle to a high value carcass that is desired on a World market. The feed fed to export quality cattle will account for the majority of the expense. Improvement of feeding system will better utilize the feedstuffs available in Ethiopia. The products available are oilseed cakes and brans from milling of grains. These products are good feed sources to cattle; but energy feeds are expensive and have limited availability. However, there are alternative sources of feedstuffs that can contribute to feeding cattle for export quality. 9. References CSA, 2003. Statistical Report on Area and Production of Temporary Crops Part III A:

Ethiopian Agricultural Sample Enumeration, 2001/02 (1994 E.C.). Central Statistical Agency, Addis Ababa.

Degu, A., Melaku, S. and Berhane, G. (2008). Supplementation of isonitrogenous oil seed cakes in cactus (Opuntia ficus-indica)-tef straw (Eragrostis tef) based feeding of Tigray highland sheep. Animal Feed Science and Technology (In press), doi:10.1016/j.anifeedsci.2008.03.014

Fekadu, D. and Ledin, I., 1997. Weight and chemical composition of the plant parts of enset (Ensete ventricosum) and the intake and degradability of enset by cattle. Livestock Production Science, 49, 249-257.

Ffoulkes, D., Espejo, S., Marie, D., Delpeche, M. and Preston, T.R., 1978. The banana plant as cattle feed: Composition and biomass production. Tropical Animal Production, 3, 45-50.

Gebremariam, T., Melaku, S. and Yami, A. (2006). Effect of different levels of cactus pear (Opuntia ficus-indica) inclusion on feed intake, apparent digestibility and body weight gain in sheep fed on tef straw. Animal Feed Science and Technology 131: 43-52

Mengistu, A., 1987. Feed resources in Ethiopia. In: Kategile, J.A., Said, A.N. and Dzowela, B.H. (Eds.). Animal Feed Resources for Small Scale Livestock Producers. Proceedings of the Second PANESA Workshop, held in Nairobi, Kenya, 11-15 November, 1985, IDRC.

Mogus, M., 1992. The Effect of Processing Method of Oilseed Cakes in Ethiopia on Their Nutritive Value: In Vitro N-Degradability and N-Metabolism in Growing Sheep Fed a Basal Diet of Maize Stover. PhD Thesis, University of Bonn, Germany, 152 p.

Nurfeta, A., 2008. Evaluation of the nutritive value of enset (Ensete ventricosum) as livestock feed in southern Ethiopia. PhD Thesis, Norwegian University of Life Sciences, Norway.

Oteino, K., Onim, J.F.M. and Semenye, P.P., 1992. Feed production and utilization by dual purpose goats in Smallholder production systems of western Kenya. In: Stares, J.E.S.,


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Said, A.N. and Kategile, J.A. (eds.). The complementarity of feed resources for animal production in Africa. Proceedings of the joint feed resources networks workshop held in Gaborone, Botswana, 4-8 March 1991. African Feeds Research Networks, ILCA (International Livestock Centre for Africa), Addis Ababa, Ethiopia.

SSA Feeds and Ethiopian Feed Resources Databases. A web-based software and database that provides information on the nutritive value of a large number of livestock feeds from sub-Saharan Africa and Ethiopia. http://www.vslp.org/FeedDB.html

Scott, G.J., 1992. Sweet potatoes as animal feed in developing countries: present pattern and future prospects. In: Machin, D. and Nyvold, S. (Eds.). Roots, Tubers, Plantains and Bananas in Animal Feeding. FAO Animal Production and Health Papers 95, pp. 183-202.

Suite, J.M., 2000. Hay and Straw Conservation – For Small Scale Farming and Pastoral Communities. FAO Plant Production and Protection Series No. 29, FAO (Food and Agriculture Organization of the United Nations), Rome.

Tegegne, F., 2001. Nutritional value of Opuntia ficus-indica as a ruminant feed in Ethiopia. In: Mondragon, C. and Gonzalez S.P. (eds.). Cactus (Opuntia spp.) as forage. FAO Plant Production and Protection Paper 169. Pp. 91-99.

Wanapat, M., Puramongkon, T. and Siphuak, W., 2000. Feeding of cassava hay for lactating dairy cows. Asian-Australasian Journal of Animal Science, 13(4), 478-482.


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Annex. Nutritive value of feeds commonly available in various parts of Ethiopia (with potential for use in feedlots)

DM OM NDF Lignin CP Ca P IVDMD ME NEm NEg

Feed type % % DM % Mcal/kg DM Roughages Hays Native grass hay 92.3 90.3 73.2 7.5 6.4 0.24 0.01 57.2 1.98 1.13 0.57 Rhodes grass hay 92.3 90.2 72.9 5.9 8.3 0.44 0.32 60.2 2.0 1.15 0.59 Oat hay 96.0 92.0 74.0 8.0 8.8 58.8 1.91 1.07 0.51 Alfalfa hay 89.3 88.0 42.6 7.2 19.2 1.6 0.23 66.3 2.37 1.49 0.90 Vetch hay 87.7 89.3 50.7 11.4 20.8 65.8 2.46 1.57 0.97 Lablab hay 91.1 87.5 41.2 6.5 18.2 1.51 0.32 66.6 2.26 1.39 0.81 Cowpea hay 92.0 90.4 43.3 7.7 14.4 1.08 0.34 68.5 2.38 1.50 0.91 Trifolium tembense (Clover), Aerial, mature

91.6 90.9 47.0 6.6 23.1 - - 69.9 2.45 1.56 0.96

Straws Cereal straws Barley straw 91.4 91.7 74.4 6.9 4.4 0.36 0.14 50.4 1.82 0.98 0.43 Wheat straw 91.8 89.0 74.7 6.2 3.1 0.25 0.08 51.3 1.74 0.90 0.36 Tef straw 91.9 91.4 72.3 5.4 4.8 1.18 0.31 53.2 1.97 1.12 0.57 Oat straw 92.2 92.1 61.9 5.2 5.7 0.25 0.18 57.9 2.12 1.26 0.69 Rice straw 93.4 81.2 2.8 0.24 0.36 Finger millet straw 91.2 91.5 69.5 4.0 3.3 0.55 0.22 55.5 1.97 1.12 0.56 Maize stover 91.0 92.1 73.5 4.7 4.0 0.31 0.10 56.1 2.10 1.25 0.68 Sorghum stover 91.3 87.7 68.9 6.1 5.6 0.55 0.25 59.5 2.02 1.17 0.61 Legume straws Faba bean straw 91.5 87.0 48.3 7.3 10.2 0.89 0.14 65.2 2.23 1.37 0.79 Field pea straw 91.6 87.4 49.1 6.2 11.6 0.64 0.18 69.8 2.36 1.48 0.89 Lentil straw 92.4 92.0 59.8 9.1 7.7 0.73 0.21 54.3 2.0 1.15 0.59 Chickpea straw 92.2 89.1 53.1 8.5 6.2 0.87 0.07 51.8 1.91 1.07 0.51 Pigeon pea straw 92.9 89.6 54.2 15.7 17.7 53.5 1.91 1.07 0.51


37

DM OM NDF Lignin CP Ca P IVDMD ME NEm NEg Feed type % % DM % Mcal/kg DM

Groundnut haulms 91.1 90.2 59.6 16.5 11.4 0.59 0.1 69.1 2.33 1.46 0.87 Haricot been haulms 91.7 90.8 63.6 8.3 5.2 51.4 1.61 0.77 0.24 Linseed straw 92.5 93.3 64.6 13.9 5.2 48.8 1.81 0.97 0.42 Other by-products Enset leaves 11.2 85.3 50.6 5.5 15.1 1.10 0.33 49.2 1.66 0.82 0.28 Enset pseudo-stem 8.3 88.2 56.5 2.4 4.17 0.47 0.27 81.5 2.87 1.92 1.28 Enset corm 18.9 91.0 43.1 1.1 3.4 0.15 0.18 88.4 3.13 2.14 1.46 Sugarcane stalk 75.8 81.2 3.3 1.46 0.08 Sweet potato vines 19.4 77.3 35 19.4 13.4 1.33 0.24 71.1 2.40 1.52 0.92 Cassava tops 21.9 90.7 35.1 8.7 22.1 1.24 0.23 68.2 2.36 1.48 0.89 Cabbage waste 14.0 88.0 27.2 14.4 80.4 2.79 1.86 1.22 Banana peel 10.0 75.0 38.4 8.3 0.54 72.9 2.48 1.59 0.99 Orange peel 28.1 94.6 19.9 5.8 1.53 0.06 82.6 2.88 1.93 1.29 Hulls and screenings Faba bean hull 89.7 96.5 69.0 9.2 0.93 0.03 56.9 1.83 0.99 0.44 Lentil hull 87.9 94.7 49.4 16.0 0.82 0.34 50.9 1.59 0.75 0.22 Rough pea hull 90.2 96.0 71.5 11.0 0.74 0.08 71.5 2.43 1.54 0.95 Field pea hull 89.3 97.1 66.3 8.0 0.87 0.18 47.8 1.46 0.62 0.09 Cottonseed hull 88.5 96.9 84.1 19.8 4.4 0.14 0.12 Sunflower hull 97.2 96.6 88.4 9.3 3.4 Wheat grain screening 88.4 96.2 15.3 Barley grain screening 94.1 91.4 61.0 7.0 7.9 56.3 Concentrates Protein sources Oilseed cakes Noug cake 92.3 89.6 39.2 8.4 31.7 0.73 1.12 61.3 2.14 1.28 0.71 Cottonseed cake 92.1 92.1 39.3 6.5 38.5 0.27 1.53 70.4 2.52 1.62 1.02 Linseed cake 92.5 92.2 32.6 6.3 29.3 0.48 0.83 70.4 2.56 1.66 1.05 Peanut cake 92.7 92.4 16.7 1.7 46.1 0.14 0.61 80.9 2.98 2.02 1.36 Sesame cake 93.1 84.3 17.4 3.3 30.7 0.77 1.54 79.3 2.55 1.65 1.05


38

DM OM NDF Lignin CP Ca P IVDMD ME NEm NEg Feed type % % DM % Mcal/kg DM

Sunflower cake 93.1 93.9 40.1 9.7 25.5 0.45 0.97 58.9 2.18 1.32 0.74 Rapeseed cake 90.9 91.2 27.6 8.1 36.4 0.69 1.18 72.3 2.58 1.68 1.07 Brewery/distillery by-products

Brewer’s dried grain 92.2 95.8 55.1 4.7 24.4 Brewer’s dried yeast 91.9 92.3 48.3 Tella atela 13.2 95.7 52.8 9.7 20.2 0.63 0.25 66.1 Areqe atela 14.0 96.2 37.0 5.1 17.8 0.61 0.59 78.8 Other by-products Whole cottonseed 91.8 94.2 50.9 10.9 23.9 0.17 0.87 56.1 2.10 1.25 0.08 Poultry litter 90.8 83.1 55.9 7.2 17.8 2.10 1.80 56.6 1.95 1.10 0.55 Energy feeds Milling by-products Wheat bran 89.7 93.4 45.9 3.4 16.8 0.15 1.2 72.4 1.37 0.78 Wheat short 91.1 95.3 19.6 1.8 18.9 Wheat middling 92.7 95.0 44.4 2.8 17.8 0.14 1.15 88.9 1.75 1.07 Rice bran 92.3 82.3 40.7 5.9 8.9 0.10 0.68 Sorghum bran 89.9 97.9 47.7 3.9 13.0 0.39 0.07 Cereal grains Maize grain 90.3 98.2 13.7 1.6 9.9 0.08 0.25 1.99 1.31 Oat grain 93.3 95.3 37.0 2.0 8.7 0.09 0.34 67.0 1.6 1.0 Barley grain 91.4 96.5 39.3 2.5 9.9 0.13 0.4 68.3 1.61 1.0 Sorghum grain 89.6 98.3 10.2 0.04

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