DUNGTREAT

CATTLE DUNG PROCESSING

In the last few decades livestock practices have evolved considerably. Highly

integrated farms, notably in cattle (Bos taurus), pig (Sus scrofa), and poultry

production, have largely disappeared, replaced by intensive systems using confined

rearing methods. Management of the large volumes of excreta produced from these

systems has meant bedding is minimized and slatted floors are employed, allowing

feces and urine to collect as slurry containing approximately 3 to 12% solids. As

intensive farming methods have proven economically effective, many adverse effects

of handling livestock wastes, particularly as slurry, have become evident. The main

problems were summarized by Pain et al. (1987):

(i) Ammonia volatilization.

(ii) Offensive odor release.

(iii) Handling problems due to the formation of crusts and sediments during storage.

In addition, other issues, such as the pollution of watercourses via surface runoff and

the spread of pathogens, are becoming ever-increasing concerns. The importance of all

these problems varies according to the nature of the waste, concerns of the farmer,

distance of neighbors, vulnerability of the surrounding environment, and current

legislation.

One of the most promising methods of disposal of cattle manure, is recycling as a

livestock feed ingredient.

Concentrate-fed animals excrete more digestible crude fiber in their feces than cattle

fed high-roughage diets

(Mc-Clure et al., 1971; Lucas et al., 1975; Newton et al., 1977).

Nutrient concentration Range in Solid Beef manure.

(Lb/ tonne)

Nitrogen (N) 7-36

Phosphorus (P) 2-6

Potassium (K) 7-17

Sulphur (S) 0.1-3

Note: multiply P by 2.3 to get P2O5 and K by 1.2 to get K2O

Adapted from Schoenau , 1997

Dried Cow dung contains 3290 Kcal/kg Calorific value

TYPICAL CHEMICAL COMPOSITION OF CATTLE MANURE

Dry matter, % 26.6

Dry matter basis

Crude protein, % 11.9

Crude fiber, % 50.9

NFE, % 31.6

Ether extract, % 0.2

Ash, % 5.4

Calcium, % 0.63

Phosphorus, % 0.17

Gross energy, Mcal/kg 4.61

Iron, ppm 612

Copper, ppm 12

Nickel, ppm 6

Cadmium, ppm 0.76

Lead, ppm 1

Mercury, ppm . 0.07

Present technology provides a wide array of innovative treatments for managing

livestock wastes. Among these, the majority of research has concentrated on biogas

(methane) production, anaerobic and/or aerobic purification, and solids separation.

While these methods have proven effective (Woestyne and Verstraete, 1995), their use

is limited, primarily due to the high cost and expertise required to operate these

mechanized systems effectively.

AMMONIA EMISSIONS

Livestock slurry is a valuable fertilizer source for crop production but its value is

reduced over time by significant losses of nitrogen (N), attributed mainly to the

volatilization of NH3

(Lauer et al., 1976; Pain et al., 1987; Hartung and Phillips, 1994).

In addition to the economic loss, NH3 emission and subsequent deposition can be a

major source of pollution, causing N enrichment, acidification of soils and surface

waters, and the pollution of ground and surface waters with nitrates

(Hartung, 1992; Sutton et al., 1995; Pain et al., 1998).

In the housed environment, NH3 emissions can also adversely affect the health,

performance, and welfare of both animals (Donham, 1990) and human attendants

(Donham et al., 1977; Donham and Gustafason, 1982).

During the last 30 years NH3 emissions in Europe have increased by more than 50%

(ApSimon et al., 1987; Sutton et al., 1995).

Intensification in livestock production has been identified as the primary contributor to

this increase and is estimated to account for 80% of yearly emissions

(Buijsman et al., 1987; Pain et al., 1998).

Consequently, many European countries have implemented legal constraints on the

spreading of livestock slurry (Burton, 1996), necessitating an increase in storage

capacity.

Storage of livestock slurry has been recognized as a major source of NH3 emissions

(Hartung and Phillips, 1994), with reported N losses ranging from 3 to 60% of initial

total N

(Muck and Steenhuis, 1982; Dewes et al., 1990).

Factors Influencing Volatilization

The concentration and type of N in livestock slurry varies according to animal species,

diet, and age.

Typically, livestock use less than 30% of N contained in their feed, with 50 to 80% of

the remainder excreted in the urine and 20 to 50% excreted in the feces. Urea is the

major nitrogenous component in urine, accounting for up to 97% of urinary N.

The exception is poultry manure, where uric acid is excreted instead of urea.

Urea is hydrolyzed by the enzyme urease, found in the feces, to ammonium (NH+4) and

bicarbonate ions.

Hydrolysis occurs rapidly, with complete conversion of urea N to NH+4 possible within a

matter of hours, depending on environmental conditions

(Muck and Richards, 1980; Beline et al., 1998).

Fecal N typically consists of 50% protein N and 50% NH+4. Mineralization of fecal

protein N mainly occurs through the activity of proteolytic and deaminative bacteria,

initially hydrolyzing proteins to peptides and amino acids and finally by deamination to

NH+4. This process occurs at a far slower rate than the hydrolysis of urea and is thought

to be a relatively unimportant source of NH+4 where livestock slurry is stored for a

short period of time

(Muck and Steenhuis, 1982).

However, where livestock slurry is stored for long periods, especially at higher

temperatures, it becomes the dominant pathway for NH+4 production

(Patni and Jui, 1991).

Reactions that govern NH3 volatilization may be represented by the following

summarized equation

(Freney et al., 1981):

[1]

The driving force for NH3 volatilization is considered to be the difference in NH3 partial

pressure between that in equilibrium with the liquid phase and that in the ambient

atmosphere. In the absence of other ionic species, this is predominately influenced by

the NH+4 concentration, pH, and temperature, although any displacement of the

equilibrium will affect NH3 emission.

OFFENSIVE ODORS

Offensive odor emanating from livestock production is of concern for intensive

systems and confined operations as the number of complaints continue to rise

(Jongebreur, 1977; O'Neill and Phillips, 1991; Misselbrook et al., 1993).

Odors from livestock slurry are due to a complex mixture of volatile compounds arising

from anaerobic degradation of plant fiber and protein

(Spoelstra, 1980; Hammond, 1989).

Chemical analysis has identified approximately 170 volatile compounds

(Spoelstra, 1980; Yasuhura et al., 1984; O'Neill and Phillips, 1992).

According to O'Neill and Phillips (1992), the most important odorous components

emitted from livestock slurry appear to be the volatile fatty acids (VFAs: p-cresol,

indole, skatole, hydrogen sulfide, and NH3), by virtue of either their high

concentrations or their low odor thresholds.

Odor can be assessed by two criteria: strength, which is measured as concentration or

intensity, and offensiveness (i.e., the perceived quality). Relationships between the

known volatile compounds and perceived olfactory responses have also been sought

by many researchers

(e.g., Schaefer, 1977; Williams, 1984; Pain et al., 1990; Mackie, 1994; Zhu et al., 1997b).

At present, though, no compound has been found suitable as a marker to predict

olfactory response. Based on olfactory measurements, the problem of odor nuisance

can be tackled by reducing either the perceived strength or offensiveness

(O'Neill and Phillips, 1991).

Reducing odor strength implies destroying or diluting odorants, whereas reducing odor

offensiveness implies modifying odorants emitted from livestock slurry.

Handling Properties

Where livestock waste is handled as a slurry, handling problems are often encountered

due to the formation of crusts and sediments during storage that make removal for

timely and accurate applications to land difficult

(Pain et al., 1987).

The rheological properties of a livestock slurry are dependant on its total solids

content (Chen, 1986).

Reducing total solids reduces viscosity and so reduces power and cost when pumping.

The composition of solids varies considerably among animal species, age, physiological

state, and diet, but generally consist of undigested plant fiber and protein.

Stimulating the microbial degradation of total solids would appear to be a more

feasible application than either control of NH3 or odor emissions, as the targeted

organic compounds are readily identified.

Work is needed to discover the microbial decay patterns of theses organic compounds

in livestock slurries and identify the responsible enzymes and bacterial genera.

Pollution to Surface Watercourses

Today there is considerable pressure on farmers to avoid water pollution.

On entry to a watercourse, livestock wastes exert a high biochemical oxygen demand

(BOD) and cause eutrophication due to high levels of nutrients, particularly N and

phosphorous (P).

Williams (1983) found that the volatile fatty acid (VFA) fraction of livestock slurry

accounted for up to 70% of its BOD.

The VFA fraction of livestock wastes has also been identified as a primary contributor

to odor

(Zhu et al., 1997c; Mackie et al., 1998; Zhu and Jacobson, 1999; Zhu et al., 1999).

Enhancing the degradation of this fraction reduction may well also lower the BOD.

However, further understanding of the microbiology pathways in livestock wastes is

required before this can be achieved.

Phosphorus runoff from land receiving slurry is another major environmental problem,

particularly from sites receiving poultry manure.

The majority of P runoff is from the dissolved reactive P fraction.

Pathogens

Many of the bacteria in livestock slurry are pathogenic and pose a heath risk.

DUNGTREAT

Present method is to treat and biodegrade the cattle dung so as odour is controlled,

pathogens are eliminated by compettion and the material is biodegraded to form

assimable nutrients for use in plants in the first phase.

1.5 Kg/Ton dung once uniformly spread over layers of each not exceeding 12.5 cm

height and total heap not exceeding 45 cm height.

Moisture is to be maintained @50% level upto 40 days.

Treatment completes in about 45 days.

In the later phases, efforts can be made to convert this biodegraded material fit for

animal consumption as a feeding stuff in the concentrate feeds @ 10% replacing the

de oiled rice or wheat brans.

DIGESTION COEFFICIENTS AND TDN OF DIETS AND MANURE ROUGHAGE

Diets: Untreated Manure roughage as fed Manure roughage

Digestibility, % 0 20% 40% 60% SE a Sign. b Mean c SEd

Dry matter 68.3 62.0 58.9 50.3 2.7 P<.001 23.0 3.3

Crude protein 57.5 54.8 50.0 41.7 2.1 P<.01 10.7 2.5

Crude fiber 29.4 31,1 33.9 31.9 5.2 N.S. 39.4 5.0

NFE 77.6 72.5 69.4 61.3 2.3 P<.O01 36.8 2.9

Ether extract 83.8 77.5 87.2 83.9 4.8 N.S. 101.2 5.3

Gross energy 64.6 59.9 57.9 49.6 3.0 P<.01 29.2 3.5

TDN 73.5 64.6 62.2 52.2 3.0 P<.001 33.0 3.8

apooled standard error of mean, n = 4.

bsignificance level of linear term of manure roughage dry matter in model (quadratic

and cubic terms, N.S.).

CCalculated by method of Kromann (1967) and Kromann et al. (1977).

dstandard error of regression, n = 16.

DIGESTIBLE AND METABOLIZABLE ENERGY AND NITROGEN VALUES OF

DIETS

Manure roughage as fed

Item 0 20% 40% 60%

SEa Significance b

Digestible energy c,

Mcal/kg,

dry weight 2.99 2.70 2.69 2.29 .14 P<.01

Metabolizable energy c

Mcal/kg, dry weight 2.59 2.33 2.35 1.98 .13 P<.O1

Percentage of gross energy lost as:

Fecal energy, % 35.4 41.1 42.1 50.4 3.02 P<.O1

Methane energy, % 6.2 5.7 5.3 4.7 .27 N.S.

Urine energy, % 2.5 2.4 1.8 1.9 .24 N.S.

Nitrogen data, daily basis:

N intake, g 153.9 162.0 190.0 166.1 8.34 N.S.

Fecal N, g 65.3 73.6 94.9 97.0 5.92 P<.O1

Urinary N, g 56.4 55.5 46.6 37.5 4.54 P<.O01

N balance, g 32.2 32.9 48.5 31.6 5.67 N.S.

N balance as % of N intake 20.9 20.3 25.5 19.0 7.00 N.S.

N balance as % of N digested 35.2 37.5 51.1 44.0 4.89 P<.05

A standard error of the mean, n = 16.

bsignificance of linear term of manure roughage dry matter (quadratic, cubic and

interaction terms, N.S.).

CDE and ME values for the manure roughage when calculated by the method of

Kromann (1967)and Kromann et aI. (1977) were 1.35 and 1.21 Mcal/kg dry weight,

respectively.

EFFECT OF MANURE ROUGHAGE IN FEEDLOT DIETS FED STEERS

ON ENERGY UTILIZATION, NEm and NEg VALUES, 124 DAYS

Manure roughage in diets, % as fed 0 O 20 20 40 40 60 60

Feed intake, % of ad libitum 50 100 50 100 50 100 50 100

Avg metabolic size, W~g J 70.6 75.4 72.3 80.7 73.5 81.3 71.9 79.8

ME in feed, Mcal/kg d. wt 2.59 2.59 2.33 2.33 2.35 2.35 1.98 1.98

ME intake/steer/day,Meal 10.85 20.03 11.25 21.62 12.69 23.59 11.03 20.36

Heat production, Meal/steer/day 10.18 16.58 10.32 16.87 10.62 18.75 9.56 15.53

NEm heat production, Meal/steer/day a 5.51 5.89 5.65 6.30 5.74 6.35 5.61 6.23

Heat increment, Meal/steer/day 4.67 10.69 4.67 10.57 4.88 12.40 3.95 9.30

Total heat/ME intake, % 93.8 82.8 91.7 78.0 83.7 79.5 86.7 76.3

Heat increment/ME intake, % 43.0 53.4 41.5 48.9 38.5 52.6 35.8 45.7

NE m heat/ME intake, % 50.8 29.4 50.2 29.1 45.2 26.9 50.9 30.6

Energy balance/ME intake, % 6.2 17.2 8.3 22.0 16.3 20.5 13.3 23.7

NE m of diet, Mcal/kg b 1.55 1.55 1.46 1.46 1.51 1.51 1.30 1.30

NEg of diet, Mcal/kg c 1.060 .875 .970 .959 1.308 .833 1.168 .879

a78.08 kcal/W'k75 X avg metabolic size, W~g.bNEm, Mcal/kg = Energy required for maintenance, Meal/day (Vance et al.,

1972)

Dry matter intake at energy equilibrium, kg/day

CNEg, Mcal/kg = Energy retained in tissues, Mcal/day

Total dry matter intake-dry matter intake at energy equilibrium, kg/day

(Vance et al., 1972)

DUNGTREAT CONTAINS

Nitrifying Bacteria, Herbal Gas adsorbants, Deodourants, Enzymes, Probiotics, Osmo

Regulators, Methyl Donors, Uni Cellar Protein Producing Microorganisms, Amino acid

producing Microorganisms.

SUGGESTED LEVEL AND METHOD OF USAGE:

USE @ 2 Kg/ MT dung ( Heap height not exceeding 9 inches) ( Maintain 35-40%

Moisture Level for 10 Days) (Room temperature). Once in a day give the heap a

turning for the first 10 Days.

Treatment time: 10 + 4 Days

REFERENCES:

Airoldi, G., P. Balsari, and R. Chiabrando. 1993. Odour control in swine houses by the use of natural zeolites: First approach to the problem. p. 701–708. In E. Collins and C. Boon (ed.) Livestock Environment IV, 4th Int. Symp., Univ. of Warwick, Coventry, UK. 6–9 July 1993. Am. Soc. Agric. Eng., St. Joseph, MI.

Al-Kanani, T., E. Akochi, A.F. MacKenzie, I. Alli, and S. Barrington. 1992. Organic and inorganic amendments to reduce ammonia losses from liquid hog manure. J. Environ. Qual. 21:709–715.[ISI]

Amon, M., M. Dobeic, T.M. Misselbrook, B.F. Pain, V.R. Phillips, and R.W. Sneath. 1995. A farm scale study on the use of De-Odorase for reducing odour and ammonia emissions from intensive fattening piggeries. Bioresour. Technol. 51:163–169.[ISI]

Amon, M., M. Dobeic, V.R. Phillips, R.W. Sneath, T.M. Misselbrook, and B.F. Pain. 1997. A farm scale study on the use of clinoptilolite zeolite and De-Odorase for reducing odour and ammonia emissions from broiler houses. Bioresour. Technol. 61:229–237.[ISI]

Andersson, M. 1994. Performance of additives in reducing ammonia emissions from cow slurry. Swedish Univ. of Agric. Sci. Dep. of Agric. Biosyst. and Technol. Rep. no. 93. JBL Publ., Sweden.

ApSimon, H., M.M. Kruse, and J.N.B. Bell. 1987. Ammonia emissions and their role in acid deposition. Atmos. Environ. 21:1939–1946.[ISI]

Barbarick, K.A., and H.J. Pirela. 1984. Agronomic and horticultural use of zeolites: A review. p. 93–103, 257–262. In W.G. Pond and F.A. Mumpton (ed.) Zeo-agriculture: Use of natural zeolites in agriculture and aquaculture. Westview Press, Boulder, CO.

Barrington, S.F., and G.R. Moreno. 1995. Swine manure nitrogen conservation in storage using sphagnum moss. J. Environ. Qual. 24:603–607.[ISI]

Barrington, S.F., P. Schuepp, R. Capp, and J. Blanchette. 1990. Peat moss to conserve swine manure nitrogen. p. 434–441. In Agriculture and food processing waste. Proc. 6th Int. Symp. on Agric. and Food Processing Wastes, Chicago, IL. December 1990. Am. Soc. Agric. Eng., St. Joseph, MI.

Beck, D.W. 1974. Molecular sieves structure. Chemistry and use. John Wiley & Sons, London.

Beline, F., J. Martinez, C. Marol, and G. Guiraud. 1998. Nitrogen transformations during anaerobically stored 15N-labelled pig slurry. Bioresour. Technol. 64:83–88.[ISI]

Berg, W., and G. Hornig. 1997. Emission reduction by acidification of slurry—Investigations and assessment. p. 459–466. In Proc. of the Int. Symp. on Ammonia and Odour Emissions from Animal Production, Vinkeloord, the Netherlands. 6–10 Oct. 1997. NVTL, Rosmalen, the Netherlands.

Bernal, M.P., and J.H. Lopez-Real. 1993. Natural zeolites and sepiolite as ammonium and ammonia adsorbent materials. Bioresour. Technol. 43:27–33.[ISI]

Bonazzi, G., C. Fabbri, and L. Valli. 1996. Options for controlling ammonia emissions from pig housing. In Proc. of Workshop on European Co-Operative Research Network on Animal Waste, Godollo, Hungary. 9–11 Oct. 1996. WRC Ref. CP 783. Hungarian Inst. of Agric. Eng., Godollo, Hungary.

Buchgraber, K. 1983. Vergleich der Wirksamkeit konventioneller und alternativer Dugungssyssteme auf dem. Gruland hinsichtlich Etrag, Futterqualitat und Gute des Pflanzenbestandes. Diss., Vienna.

Buijsman, E., H.F.M. Mass, and W.A.H. Asman. 1987. Anthropogenic NH3 emissions in Europe. Atmos. Environ. 21:1009–1022.[ISI]

Burnett, W.E., and N.C. Dondero. 1970. Control of odours from animal wastes. Trans. ASAE 13:221–231.

Burton, B.H. 1996. Processing strategies for farm livestock slurries to minimise pollution and to maximise nutrient utilisation—An EU collaboration. p. 5–10. In G. Parafait et al. (ed.) Ingenieries EAT—Animal Manures and Environment in Europe. Dec. 1996. Antony, Cemagfef, France.

Chen, Y.R. 1986. Rheological properties of sieved beef-cattle manure slurry: Rheological model and effects of temperature and solids concentration. Agric. Manure 15:17–33.

Cole, C.A., H.D. Bartlett, D.H. Buckner, and D.E. Younkin. 1976. Efficacy of certain chemical and biological compounds for control of odor from anaerobic liquid swine manure. J. Anim. Sci. 42:1–7.[ISI]

Court, M.N., R.C. Stepphen, and J.S. Waid. 1964. Toxicity as a cause of the inefficiency of urea as a fertilizer. J. Soil Sci. 15:42–48.[ISI]

Daigle, J.Y., A. Arseneau, and A. Robichaud. 1987. Sphagnum peat: A tool for liquid hog manure management. p. 173–176. In Wetlands/Peatlands Symp. 1987, Edmonton, AB, Canada. Wetlands/Peatlands `87 Publ., Ottawa, ON, Canada.

Dewes, T. 1987. Chemical and microbial changes during the fermentation of liquid cattle manure treated with Agriben and its ingredients. p. 323–329. In Proc. from Agric. Waste Manage. and Environ. Protection. 4th Int. Symp. of CIEC, Braunschweig Federal Republic of Germany. 11–14 May 1987. Vol. 2. Goltze-Druck, Gottingen, Germany.

Dewes, T., L. Schmitt, E. Valentin, and E. Ahrens. 1990. Nitrogen losses during the storage of liquid livestock manures. Biol. Wastes. 31:241–250.[ISI]

Donham, K.J. 1990. Relationships of air quality and productivity in intensive swine housing. J. Agric. Practice 10:15–18.

Donham, K.J., and K.E. Gustafason. 1982. Human occupational hazards from swine confinement. Ann. Am. Conf. Gov. Hyg. 2:137–142.

Donham, K.J., M.J. Rubino, T.D. Thedell, and J. Kammermeyer. 1977. Potential health hazards to agricultural workers in swine confinement buildings. J. Occup. Med. 19:383–387.[ISI] [Medline]

Eekert, M.H., and A.D.J. en Wijbenga. 1992. Microbiele verzuring van varkensdrijfmest. Nederlands Instituut voor Koolhydraat Onderzoek. NIKO-TNO. September 1992. Univ. of Groningen Press, the Netherlands.

Elsasser, M., and H. Kunz. 1988. Effects of slurry with and without additives on forage yields and quality of a meadow in the alpine foothills. Wirtschaftseigene Futter 34:48–65.

Emanuel, A.G. 1965. Potassium permanganate offers new solutions to air pollution control. Air Engineering. September 1965.

Faith, W.L. 1964. Odour control in cattle feed yards. J. Air Pollut. Control Assoc. 1411:459–460.

Freney, J.R., O.T. Denmead, I. Watanbe, and E.T. Craswell. 1981. Ammonia and nitrous oxide losses following applications of ammonia sulfate to flooded rice. Aust. J. Agric. Res. 32:37–45.[ISI]

Grubbs, R.B. 1979. Bacteria supplimentation what it can and can't do. Paper presented at the 9th Eng. Foundation Conf. in Environ. Eng. in the Food Processing Ind., Pacific Grove, CA. 27 Feb. 1979. ASCE, Reston, VA.

Hammond, E.G., C. Heppner, and R. Smith. 1989. Odour of swine waste lagoons. Agric. Ecosyst. Environ. 25:103–110.[ISI]

Hammond, W.C., D.L. Day, and E.L. Hansen. 1968. Can lime and chlorine suppress odours in liquid hog manure? Agric. Eng. 49:340–343.[ISI]

Hartung, J. 1992. Emissions and control of gases and odorous substances from animal housing and manure stores. Zentralbl. Hyg. Umweltmed. 192:389–418.[ISI] [Medline]

Hartung, J., and V.R. Phillips. 1994. Control of gaseous emissions from livestock buildings and manure stores. J. Agric. Eng. Res. 57:173–189.[ISI]

Headon, D.R., K. Buggle, A. Nelson, and G. Killeen. 1991. Glycofractions of the yucca plant and their role in ammonia control. p. 95–108. In T.P. Lyons (ed.) Biotechnology in the feed industry. Allttech, Nichoasville, KY.

Headon, D.R., and G. Walsh. 1993. Yucca schidigera extracts and ammonia control. p. 686–693. In E. Collins and C. Boon (ed.) Livestock Environment IV, 4th Int. Symp., Univ. of Warwick, Coventry, UK. 6–9 July 1993. Am. Soc. Agric. Eng., St. Joseph, MI.

Heck, A.F. 1931. Conservation and availability of nitrogen in farm manures. Soil Sci. 31:335–363.

Hendriks, J.G.L., D. Berckmansand, and C. Vincker. 1997. Field tests of bio-additives to reduce ammonia emission from pig houses. p. 707–714. In Proc. of the Int. Symp. on Ammonia and Odour Emissions from Animal Production, Vinkeloord, the Netherlands. 6–10 Oct. 1997. NVTL, Rosmalen, the Netherlands.

Hendriks, J.G.L, and M.G.M. Vrielink. 1996. Anzuren van varkensmest via het voer. Praktijk-oderzoek varkenshoulderij. June 1996. Rosmalen, the Netherlands.

Hendriks, J.G.L., and M.G.M. Vrielink. 1997. Reducing the emission from pig houses by adding or producing organic acids in pig slurry. p. 493–501. In Proc. of the Int. Symp. on Ammonia and Odour Emissions from Animal Production, Vinkeloord, the Netherlands. 6–10 Oct. 1997. NVTL, Rosmalen, the Netherlands.

Hoeskma, P., N. Verdoes, and G.J. Monteny. 1993. Two options for manure treatment to reduce ammonia volatilisation from pig housing. p. 301–306. In European Assoc. for Animal Prod. Publ. 69. EAAP, Wageningen, the Netherlands.

Hollenback, R.C. 1971. Manure odour abatement using hydrogen peroxide. Rep. no. 5638-R. Food Machinery Corp., Princeton, NJ.

Huang, Z.T., and A.M. Petrovic. 1994. Clinoptilolite zeolite influence on nitrate leaching and nitrogen use efficiency in simulated sand based golf greens. J. Environ. Qual. 23:1190–1194.[ISI]

Husted, S., L.S. Jensen, and S.S. Jorgensen. 1991. Reducing ammonia loss from cattle slurry by the use of acidifying additives: The role of the buffer system. J. Sci. Food Agric. 57:335–349.[ISI]

Johnston, N.L., C.L. Quarles, D.J. Fagerberg, and D.D. Caveny. 1981. Evaluation of yucca saponin on performance and ammonia suppression. Poul. Sci. 60:2289–2295.[ISI]

Jongebreur, A. 1977. Odour problems and odour control in intensive livestock husbandry farms in the Netherlands. Agric. Environ. 3:259–265.[ISI]

Jutras, P.J., C. Weil, D. Martin, and R.D. Richard. 1980. Progress in the control of swine odours with ozone. Paper no. 80-412. Am. Soc. Agric. Eng., St. Joseph, MI.

Kemme, P.A., A.W. Jongloed, B.M. Dellaert, and F. Krol-Kramer. 1993. The use of Yucca schidigera extract as a `urease inhibitor' in pig slurry. p. 330–335. In Proc. of the 1st Int. Symp. on Nitrogen Flow in Pig Production and Environ. Consequenses, Wageningen, the Netherlands. 8–11 June 1993. EAAP Publ. no. 69. PUDOC, Wageningen, the Netherlands.

Kibble, W.H., C.W. Raleigh, and J.A. Sheperd. 1972. Hydrogen peroxide for industrial pollution control. In Proc. of the 27th Purdue Ind. Waste Conf., Purdue Univ., Lafayette, IN. Purdue Univ. Publ., Lafayette, IN.

Koelikker, J.K., M.L. Hellickson, J.R. Miner, and H.S. Nakane. 1978. Improving poultry house environments with zeolite. Paper no. 78-4044. Am. Soc. Agric. Eng., St. Joseph, MI.

Komarowski, S., and Q. Yu. 1997. Ammonium ion removal from wastewater using Australian natural zeolite: Batch equilibrium and kinetic studies. Environ. Technol. 18:1085–1097.[ISI]

Krieger, R., J. Hartung, and A. Pfeiffer. 1993. Experiments with feed additives to reduce ammonia emmisions from pig fattening houses—Preliminary results. p. 295–300. In Proc. of the 1st Int. Symp. on Nitrogen Flow in Pig Production and Environ. Consequenses, Wageningen, the Netherlands. 8–11 June 1993. EAAP Publ. no. 69. PUDOC, Wageningen, the Netherlands.

Kroodsma, W., and N.W.M. Ogink. 1997. Volatile emissions from cow cubicle houses and its reduction by immersion of the slats with acidified slurry. p. 475–483. In Proc. of the Int. Symp. on Ammonia and Odour Emissions from Animal Production, Vinkeloord, the Netherlands. 6–10 Oct. 1997. NVTL, Rosmalen, the Netherlands.

Lauer, D.A., D.R. Bouldin, and S.D. Klaususner. 1976. Ammonia volatilization from dairy manure spread on the soil surface. J. Environ. Qual. 5:131–141.[ISI]

Liao, C.M., and D.S. Bundy. 1994. Bacteria additives to the changes in gaseous mass-transfer from stored swine manure. J. Environ. Sci. Health. 296:1219–1249.

MacKenzie, A.F., and J.S. Tomar. 1987. Effect of added monocalcium phosphate monohydrate and aeration on nitrogen retention by liquid hog manure. Can. J. Soil. Sci. 67:687–692.[ISI]

Mackie, R.I. 1994. Microbial production of odor components. p. 18–19. In Proc. of Int. Round Table on Swine Odor Control, Ames, IA. 13–15 June 1994. Iowa State Univ. Publ., Ames.

Mackie, R.T., P.G. Stroot, and V.H. Varel. 1998. Biochemical identification and biological origin of key odor components in livestock waste. J. Anim. Sci. 76:1331–1342.[Abstract/Free Full Text]

Mader, J.R., and M.C. Brumm. 1987. Effect of feeding sarsaponin in cattle and swine diets. J. Anim. Sci. 65:9–15.[ISI] [Medline]

Martinez, J., J. Jolivent, F. Guiziou, and G. Langeoire. 1997. Ammonia emissions from pig slurries. Evaluation of acidification and the use of additives to reduce losses. p. 475–483. In Proc. of the Int. Symp. on Ammonia and Odour Emissions from Animal Production, Vinkeloord, the Netherlands. 6–10 Oct. 1997. NVTL, Rosmalen, the Netherlands.

Miner, J.R. 1984. Use of natural zeolites in the treatment of animal wastes. p. 257–262. In W.G. Pond and F.A. Mumpton (ed.) Zeo-agriculture: Use of natural zeolites in agric. and aquaculture. Westview Press, Boulder, CO.

Miner, J.R., S.N. Raja, and W. McGregor. 1997. Finely ground zeolite as an odour control additive immediately prior to sprinkler application of liquid dairy manure. p. 717–720. In Proc. of the Int. Symp. on Ammonia and Odour Emissions from Animal Production, Vinkeloord, the Netherlands. 6–10 Oct. 1997. NVTL, Rosmalen, the Netherlands.

Miner, J.R., and R.S. Stroh. 1976. Controlling feedlot surface emmision rates by application of commercial products. Trans. ASAE 19:533–538.[ISI]

Misselbrook, T.H., C.R. Clarkson, and B.F. Pain. 1993. Relationship between concentration and intensity of odours for pig slurry and broiler houses. J. Agric. Eng. Res. 55:163–169.[ISI]

Molloy, S.P., and H. Tunney. 1983. A laboratory study of ammonia volatilisation from cattle and pig slurry. Irish J. Agric. Res. 22:37–45.[ISI]

Moore, P.A., Jr., T.C. Daniel, D.R. Edwards, and D.M. Miller. 1995. Effects of chemical amendments on ammonia volatilization from poultry litter. J. Environ. Qual. 24:293–300.[ISI]

Muck, R.E., and B.K. Richards. 1980. Losses of manurial N in free-stall barns. Agric. Manure 7:65–93.

Muck, R.E., and T.S. Steenhuis. 1982. Nitrogen losses from manure storage. Agric. Manure 4:41–54.

Mumpton, F.A., and P.H. Fishman. 1977. The application of natural zeolites in animal science and aquacluture. J. Anim. Sci. 45:1188–1203.[ISI]

Nakaue, H.S., J.K. Koelliker, and M.L. Pierson. 1981. Studies with clinoptilolite in poultry: II. Effect of feeding broilers and the direct application of clinoptilolite zeolite on clean and reused broiler litter on broiler performance and house environment. Poul. Sci. 60:1221–1228.[ISI]

Ogink, N.W.M., and W. Kroodsma. 1996. Reduction of ammonia emissions from a cow cubical house by flushing with water or a formalin solution. J. Agric. Eng. Res. 53:23–50.

O'Halloran, L.P., and A. Sigrest. 1993. Influence of incubating monocalcium phosphate with liquid hog manure on inorganic phosphorous and phosphourous availability in two Quebec soils. Can. J. Soil. Sci. 73:371–379.[ISI]

O'Neill, D.H., and V.R. Phillips. 1991. A review of the control of odour nuisance from livestock buildings. Part 1: Influence of the techniques for managing waste within the building. J. Agric. Eng. Res. 50:1–10.[ISI]

O'Neill, D.H., and V.R. Phillips. 1992. A review of the control of odour nuisance from livestock buildings. Part 3: Properties of the odorous substances which have been identified in livestock wastes or in the air around them. J. Agric. Eng. Res. 53:23–50.[ISI]

Pain, B.F., R.B. Thompson, L.C.N. De La Cremer, and L. Ten Holte. 1987. The use of additives in livestock slurries to improve their flow properties, conserve nitrogen and reduce odours. p. 229–246. In Van Der Meer et al. (ed.) Development in plant soil sciences. Animal manure on grassland and fodder crops. Fertiliser or waste? Martius Nijhoff Publ., Dordrecht, the Netherlands.

Pain, B.F., R.B. Thompson, Y.J. Rees, and J.H. Skinner. 1990. Reducing nitrogen losses from cattle slurry applied to grassland by the use of additives. J. Anim. Sci. 45:1188–1203.

Pain, B.F., T.J. Van der Weeden, B.J. Chambers, V.T. Phillips, and S.C. Jarvis. 1998. A new inventory for ammonia emissions from U.K. agriculture. Atmos. Environ. 32:309–313.[ISI]

Patni, N.K. 1992. Effectiveness of manure additives. Report for Ontario pork producers. The Centre for Food and Animal Res., Research Branch, Agriculture Canada, Central Exp. Farm, Ottawa, ON, Canada.

Patni, N.K., and P.Y. Jui. 1991. Nitrogen concentrations in dairy-cattle slurry stored in farm tanks. Trans. ASAE 342:609–615.

Peltola, I. 1986. Use of peat as a litter for milking cows. p. 181–187. In Odour prevention and control of organic sludge and livestock farming. Elsevier Appl. Sci. Publ., London.

Ritter, W.F. 1981. Chemical and biochemical odour control of livestock wastes: A review. Can. Agric. Eng. 23:1–4.[ISI]

Ritter, W.F. 1989. Odour control of livestock manure: State-of-the-art in North America. J. Agric. Eng. Res. 42:51–62.[ISI]

Ritter, W.F., N.E. Collins, and R.P. Eastburn. 1975. Chemical treatment of liquid dairy manure to reduce malodours. p. 381–384. In Managing Livestock Manure, Proc. 3rd Int. Symp. on Livestock Manure. Publ. PROC-275. Am. Soc. Agric. Eng., St. Joseph, MI.

Safley, L.M., D.W. Nelson, and P.W. Westerman. 1983. Conserving manurial nitrogen. Trans. ASAE 26:1166–1170.[ISI]

Schaefer, J. 1977. Sampling, characterisation and analysis of malodours. Agric. Eng. Res. 3:121–127.

Smith, K., A. Drysdale, and D. Saville. 1980. An investigation into the effectiveness of some odour control treatments in stored pig manure. Project Rep. 24. New Zealand Agric. Eng. Inst., Lincon College, Canterbury, New Zealand.

Spoelstra, S.F. 1980. Origin of objectionable odorous compounds in piggery manure and the possibility of applying indicator components for studying odour development. Agric. Environ. 5:241–260.[ISI]

Stevens, R.J., R.J. Laughlin, and J.P. Frost. 1989. Effect of acidification with sulphuric acid on the volatilisation of ammonia from cow and pig slurries. J. Agric. Sci. 113:389–395.[ISI]

Subair, S. 1995. Reducing ammonia volatilisation from liquid hog manure by using organic amendments. M.Sc. thesis. McGill Univ., Montreal, QC, Canada.

Sutton, M.A., C.J. Place, M. Eager, D. Fowler, and R.I. Smith. 1995. Assessment of the magnitude of ammonia emissions in the United Kingdom. Atmos. Environ. 29:1393–1411.[ISI]

Turner, C., and C.H. Burton. 1997. The inactivation of viruses in pig slurries: A review. Bioresour. Technol. 61:9–20.[ISI]

Ulich, W.F., and J.P. Ford. 1975. Malodour reduction in beef cattle feedlots. p. 369–371. In Managing Livestock Manure, Proc. 3rd Int. Symp. on Livestock Manure. Publ. PROC-275. Am. Soc. Agric. Eng., St. Joseph, MI.

Vandre, R., and J. Clemens. 1996. Studies on the relationship between slurry pH, volatilisation processes and the influence of acidifying additives. Nutr. Cycl. Agroecosyst. 47:157–165.[ISI]

Varel, V., H. Nieenaber, and B. Byrnes. 1997. Urease Inhibitors reduce ammonia emmssion from cattle manure. p. 721–728. In Proc. of the Int. Symp. on Ammonia and Odour Emissions from Animal Production, Vinkeloord, the Netherlands. 6–10 Oct. 1997. NVTL, Rosmalen, the Netherlands.

Warburton, D.J., J.N. Scarborough, D.L. Day, A.J. Muehling, S.E. Curtis, and A.H. Jensen. 1980. Evaluation of commercial products for odour control and solids reduction of liquid swine manure. p. 309–313. In Livestock waste: A renewable resource. Am. Soc. Agric. Eng., St. Joseph, MI.

Watkins, B.D., S.M. Hengemuehle, H.L. Person, M. Yokoyama, and S.J. Masten. 1997. Ozonation of swine manure wastes to control odors and reduce the concentrations of pathogens and toxic fermentation metabolites. Ozone Sci. Eng. 19:425–437.[ISI]

Williams, A.G. 1983. Organic acids, biochemical oxygen demand and chemical oxygen demand in the soluble fraction of piggery slurry. J. Sci. Food. Agric. 34:212–220.[ISI] [Medline]

Williams, A.G. 1984. Indicators of piggery slurry odour offensiveness. Agric. Manure 10:15–36.

Witter, E. 1991. Use of ClCa2 to decrease ammonia volatilisation after application of fresh and anaerobic chicken slurry to soil. J. Soil Sci. 423:369–380.

Witter, E., and H. Kirchmann. 1989. Peat, zeolite and basalt as adsorbents of ammoniacal nitrogen during manure decomposition. Plant Soil 115:4.

Woestyne, M.V., and W. Verstraete. 1995. Biotechnology in the treatment of animal manure. p. 311–327. In Biotechnology in animal feeds and animal feeding. VCH Verlagsgesellschaft mbH, Weinhiem, Germany.

Wu, J.J., S.H. Park, S.M. Hengemuehle, M. Yokoyama, H.L. Person, J.B. Gerrish, and S.J. Masten. 1999. The use of ozone to reduce the concentration of malodorous metabolites in swine manure slurry. J. Agric. Eng. Res. 72:317–327.[ISI]

Wu, J.J., S.H. Park, S.M. Hengemuehle, M. Yokoyama, H.L. Person, and S.J. Masten. 1998. The effect of storage and ozonation on the physical, chemical, and biological characteristics of swine manure slurries. Ozone Sci. Eng. 20:35–50.[ISI]

Yasuhura, A., K. Fuwa, and M. Jimbu. 1984. Identification of odorous compounds in fresh and rotten swine manure. Agric. Biol. Biochem. 48:3001–3010.

Yu, J.C., C.E. Issac, R.N. Colemen, J.J.R. Feddes, and B.S. West. 1991. Odourous compounds from treated pig manure. Can. Agric. Eng. 33:131–136.[ISI]

Zhu, J., D.S. Bundy, L. Xiwei, and N. Rashid. 1997a. The hindrance in the development of pit additive products for swine manure odor control—A review. J. Environ. Sci. Health. A 32:2429–2448.[ISI]

Zhu, J., D.S. Bundy, L. Xiwei, and N. Rashid. 1997b. Controlling odor and volatile substances in liquid hog manure by amendment. J. Environ. Qual. 26:740–743.[ISI]

Zhu, J., D.S. Bundy, L. Xiwei, and N. Rashid. 1997c. A procedure and its application in evaluating pit additives for odor control. Can. Agric. Eng. 39:207–214.[ISI]

Zhu, J., and L.D. Jacobson. 1999. Correlating microbes to major odorous compounds in swine manure. J. Environ. Qual. 28:737–744.[ISI]

Zhu, J., G.L. Riskowski, and M. Torremorell. 1999. Volatile fatty acids as odour indicators in swine manure—A critical review. Trans. ASAE 42:175–182.[ISI]