.Management and Control of Common Diseases of Monogastric

(Rabbits and Pigs)

Extension Bulletin ~o ....... .

Livestock series No .......... .

Published by

National Agricultural Extension and Research Liaison Services

Ahmadu Bello University Zaria.

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AKNOWLEDGEME:\TT

1 express my profound gratitude and appreciation to the members of Livestock and Fisheries Programme in house publication review commit­tee for their valuable contributions, suggestions and corrections while re­viewing the manuscript. I am also grateful to all the sc ientists whose materials and publications were consulted.

(Dr 0 . C. Jegede)

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TABLE OF CONTENTS

Introduction .................. . ...................... ...... ................. 5 The healthy Rabbit.. ...... .......................................... .. ..... 5 Stress ..................... .. ........ .. .. .. ................................... . 6 Disease organisms .... . .......... ............. . . . . ... . ..................... 7 Cleaning and disinfecting hutches ................... ....... ............ ... .... 8 Preventing injury . ......... ......... . ......................... .. ............... 11 Rabbit examination ......................................................... 13 Common Health and Disease prob lems .............................. . ... 14 The main diseases ..... .. .......... .. . ... .. .................................. 14 Coccidiosis ....... . ........................................................ 16 Problems of the respiratory tract. .... .. ........... ... .. ..... ..... . ........ 17 Ear and skin mange . ............ . ...... ................. . ................. 17 Other disease and health problems ....................................... 19 Pigs ................ . ..... . .. . ..... . ............. . . ...... . . . ............... .. .. 21 D isease prevention .................. . ..... .. . ......... .. .. . ... .. .......... . 21

Parasites .............................. . .. .. ............... .. .. ......... .... . . ... 2 1 External parasites ..... .. .... .............. .. ..... .................... . ... .. . 21 Mange mites ........................... . ...... ...... . .. ...... . ....... .. ... . 2 1 Ticks .. . . .. ........... . .... . ................ . ..... . . ... ...................... 22 Lice and fleas . . .. . . ..... ................ . ............... .. ... . ......... ..... 22 Flies ................................ . ..................... . .. . ....... . . ..... 22 Internal parasites . . .. ....... .. ................ .. ...................... ... .. 23 Infectious diseases ................................. . ...... .. . . .... . ......... 26 Afiican swine fever ................. . . .. . . . ...................... . .. .. . ... 26 Foot and mouth disease ................................................... 26 Pneumonia . . ............. . .............. . .... .. ....... .... ............ . .... 27 Tetanus .... . .. . . .... . . ............... . ........ . ...... . ...................... 27 Diseases that cause ferti lity disorder. ..................................... 27

Brucellosis .......... . ......... ... . . ...... . . .... . ... .... ......... .. . ...... . . 27

Weil 's disease (Leptospirosis) ............. ...... . ..... . ............... . .. 28 Feed Related Diseases .......... ... ............ ... ...... . ............... . ... 29

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Anemia or blood deficiency .......... .. . ... ......................... ...... . 29 Constipation .. .. . .. ... . ....... . ..... .............................. ........ ..... 29 :\one specific diseases .......... . . .... ..... ..... .. ... . ......... .... ... ..... .... 29

Bibliography ........... ............. ............ ...... ....... .. .......... .... .. ........ ..... .... 31

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Introduction Like all animals, rabbits require proper care if they are to (re)produce well. Before going to s leep at night, as well as in the day, the farmer should keep a close eye on them. It is not enough to see that the animal is sick, one should learn to see whether the animal will be sick; it is not enough to see that the doe has made a nest and kindled, one should know before hand that she will make a nest and kindle. Animals have no holidays even on Christmas Eve they need feed, they will kindle during

Easter week or they may get sick during Ramadan.

The Healthy Rabbit The healthy rabbit may become an unhealthy and diseased rabbit if its circumstances become unfavourable, that is where stress and disease organisms are present. The rabbit keeper should there­fore seek ro maintain a healthy rabbit lhal is unstressed and in

whose environment there are as few disease organisms as pos­sible. A healthy rabbit, is always a well-fed rabbit, therefore pro­vide a balanced ration. The signs of a healthy rabbit are:

o Normal eating and drinking o Alertness, interest and curiosity o Self-grooming o Shiny, smooth clean fur, especially on the front paws and

around the anus o Clear bright eyes without discharge o 1 ormal silent breathing. o Normal faeces, no soft faeces on the hutch floor;

o Gaining weight or, if an adult, maintaining its weight,

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Situations that make rabbits susceptible to diseases are .l> Insufficient water .l> An unbalanced diet deficient in energy, protein, minerals

or vitamins; )> Insufficient food )> Toxic or poisonous foods;

r High fibre-only foods that cause the rabbit to blow up like a ball;

.l> Sour. dirty foods that cause diaiThea. > Dit1y, hutches and badly ventilated butches that promote

an increase in the number of disease organisms. The signs of ill-health are the opposite of the above, for example, failure to eat, loss of weight, dian·hoea, discharge from the eyes or ears. noisy breathing, a rough staring coat, soft faeces on the hutch floor. Because of the rabbits fur, weight loss may not be noticed if rabbits are not weighed. An alternative to weighing is to handle the rabbits to check on their body condition. If the fingers are regularly run over a rabbit's ribs and spine it should be possible to detect changes in its body condition which can serve to aleti the farmer/keeper to the onset of a problem of undemutrition or disease. Some rabbits are apparently disease­resistant and do not become diseased when other rabbits are sick and unhealthy. Obviously, rabbits that are never diseased should be retained for breeding.

Stress Stress is any cha llenge to any system of the rabbit; for example, its temperature control system, its digestive system and its nor­mal behaviour pattern. Pregnancy, giving birth, lactation, wean­ing and mating are all periods of natural and unavoidable stress .

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The rabbit keeper should try to minimize avoidable stress. Avoidable stress can be caused by many factors but the many stresses can be minimized by.

l . Correct hutch design - it should be windproof and water-proof.

2. Correct placement of the hutch 3. Routine management steps to avoid heat stress 4. Avoidance of over crowding in hutches 5. Exclusion of dogs, snakes and noisy visitors 6. An adequate well balanced diet 7. Over all good management particularly that of clean and

dry floors and sufficient beddings reduces incidences of stress and diseases in your rabbitry. Remember cleanli­ness is next to godliness.

Disease Organisms Disease organism can be kept away from the rabbits and the con­centration of disease organisms can be kept low in a number of ways, such as:

)> Designing hutches to ensure good ventilation without draughts and that allow faeces and urine to fall away from the rabbits;

)> Building hutches from new wood or materials that have not been used previously in rabbit hutches;

)> Cleaning and disinfecting hutches thoroughly and regu­larly to kill any disease organisms present;

)> Buying rabbits from keepers who have healthy rabbits; )> Keeping new rabbits isolated for two weeks on arrival and

checking them regularly for any sign of disease; )> Feeding only clean, fresh, food and water;

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);;> Separating any sick animals from the healthy ones; );;> Not mixing rabbits unnecessarily (be careful when shar­

ing a buck with another keeper) );;> Thoroughly cleaning a hutch where a rabbit has died be­

fore reusing it; );;> Resting hutches after cleaning. Two to three weeks rest­

ing period is adequate.

Cleaning and disinfecting hutches To protect the herd 's health, keep the rabbitry equipment in good

sanitary condition. Remove manure and soiled bedding at fre­quent internals and contaminated feed daily. Inspect water crocks and feed troughs daily and wash them frequently with hot, soapy

water. Rinse them in clear water, allow them to drain well and place them in the direct rays of the sun to dry with regular turn­ing to ensure that all parts is exposed to sun light.

To prevent or control a disease or parasitic infection, thoroughly disinfect hutches and equipment, which has been oc­cupied or used by sick animals or where excessive mmiality has occurred. To clean and disinfect the hutches, scrap out all diti and feaces wash with hot soapy water and with disinfectant solu­tion recommended by a veterinarian or a livestock extens ion of­ficer and dry in the sun. Cleaning and disinfecting allow the rab­bit keeper to attack the disease organisms before they attack the rabbits . The hutches should be dried in the sun with regular turn­

ing to ensure that all parts of the hutch are exposed to the sun as much as possible. Drying in the sun will allow the sun's ultravio­let rays to disinfect the hutch without any cost and resting for two to three weeks before restocking with rabbits. Maintaining good sanitary conditions in the rabbitry is a preven-

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tive measure for controlling disease in the herd. Watch out for the appearance of any sign that might indicate disease. Isolate animals suspected ofhaving disease(s) at least two weeks to de­termine definitely whether they are dangerous to the health of the herd. Place newly acquired rabbits in quarantine at least two weeks for the same reason. Bum or bury dead animals.

Preventing injuries The hind quarters of rabbits usually suffer Paralysis as a result of improper handling or from injuries caused when rabbits s lip in the hutch while exercising or attempting to escape from preda­tors, especially around kindling time. Such slipping usually oc­curs at night. Common injuries include dislocated veriebral ones, damaged nerve tissue, or strained muscles or tendons. If the injury is wild, the animal may recover in a few days. Make the injured animal confortable and feed it a balanced diet. If it does

not improve within a week, destroy it to prevent unnecessary suffering. It is important, therefore, that your rabbits be pro­vided with quiet comforiable surroundings and be protected from predators and unnecessary disturbances so as to reduce injuries. Toe nails are another source of injury to rabbits. The toe nails of rabbits confined in hutches do not wear nor­mally. They may even become long enough to cause foot defor­mity. The nails may also catch in the wire mesh floor and cause injury and suffering. Periodically cut the nails with side cutting pliers, sharp scissors or human nail clippers (Figure l ). Cut be­low the tip of the cone in the toenail. The cone can be observed by holding the foot up to daylight. The rabbit should be taken to a well illuminated area and restrained. In such an environment, it

will be seen that the rabbit's nail has a dark area and towards the

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end a light area. It is the light area, which should be trimmed. Start at the end and trim small pieces at a time, so as to prevent bleeding or injury to sensitive spots. Do not cut a ll the way to the dark area, as this will cause pain and bleeding.

cut only the li11hl il rea

Fig 1 b Over grown nail before and after trimming

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Examination a Rabbit A thorough examination of rabbit should be carried out

when a new rabbit is being bought or prior to selection for breed­ing. Below is a list of points that should be checked if any of these are present then the rabbit may not be sound health wise. Observe the rabbit without disturbing it.

~ Does it look unhealthy? ~ Is it's head on one side? ~ Is it shaking its head excessively?

~ Is it sitting apart from the other rabbits? ~ Are there any soft faeces present in the hutch? ~ Are the hard faeces n01mal?

Take the rabbit from the hutch and place it on flat surface at chest height in a well- lit place. Run your fingers gently over its body.

~ Is the rabbit's abdomen swollen and distened? }> Ts it too thin and bony ~ Is the fur rough and coarse to the touch ~ Are there patches of skin with no hair? ~ Are the nostrils clear or running with fluid? ~ Are the eyes dull and rolling? ~ Are there any scales on the skin? ~ Hold the rabbit in a sitting position ~ Is the fur around the anus dirty with faeces? ~ Are there any sores on the bottom of the feet?

Let the rabbit free and find out the following: ~ Is it lame or unbalanced? ~ If possible weigh the rabbit. Is it the wrong weight for

its age?

If you have answered "yes" to any of the above questions your

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rabbit probably has a health problem. Consult your Veterinarian or a Livestock Extension Officer.

Sings of sickness. A sick rabbit becomes dull and inactive. Its eyes tum pale, It loses weight and it sometimes produces a watery discharge from the

anus, nose and eyes. The faeces of a rabbit can sometimes give a clue that the animal is sick. Fig. 3 gives an indication of what to look for.

a) ~otmal faeces consist of solid. round and tablet like drop­pings. The fibre content can easily be seen. There is little odour unless the fanner brings the faeces close to his nosnils. A sick rabbit 's droppings can sometimes be smelt as one approaches the hutch.

b) A 4 to 5 month old rabbit discharges small, tablet-like faeces, bound together in a long cluster; the length of the cluster vaties from 2 to 5 em. the faeces are shiny and sticky and are believed to be a left over of the edible dis­charge which the rabbit consumes at night. Bucks in their puberty stage and pregnant does sometimes discharge such faeces.

c) About 1 to 2 weeks before delivery, the doe discharges droppings similar in size to those in (a) but linked to­gether. They may continue to discharge such droppings

until 3 to 4 days after delivery. d) The faeces of a sick rabbit are watery and sticky. They

may contain worms (white and coiled). Watery discharges usually indicate that the rabbit has diarrhea.

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fl ) d)

Fig 2 Determining the health of a rabbit from the faeces

Common Health and Disease problems of Rabbits The main causes of mortality (death) in rabbits are probably in­testinal problems and diseases of the respiratory organs. These are sometimes indirect consequences of intestinal problems causing lower resistance. Other main causes of mmiality are a whole group of diseases of which myxomatosis is the most well known but least occurring disease and problems of skin para­sites are bothersome but hardly ever fatal and are easily cured. In this, the emphasis will however be on the prevention of disease. Prevention is easier, cheaper and it is the most logical thing to do. Only if "bad luck" strikes does curing come in but success even then is far from guaranteed and medicine is often not easy to get and may cost you a lot of money. Thus the main diseases of rabbit are intestinal in nature and this include:

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THE MAl~ DISEASE Intestinal problems Intestinal problems includes diseases such as coccidiosis, bloat, enteritis, diarhoea, etc which are refetTed to as "enteritis com­plex"

Coccidiosis The most common intemal parasites of rabbits are coccidia. One species attacks the lining of the bile ducts and causes liver coc­cidiosis. which is recognized on post-mortem examina tion by the presence of whi te spots in the liver. Yiost species of coc­cidia attack the lining of the intestine and may cause lack of ap­petite and du llness fo llowed by severe diaiThoea. leading to de­hydration and rapid death. The dian·hea may be blood sta ined. (note: a fatal liver coccidiosis hardly ever gives diarhoea) Coccidia are commonly found in the intestine wi thout causing any obvious effects but a period of stress, such as weaning or bad weather may result in them multiplying rapidly. The ensuing diatThoea dirties all the fur around and below the anus . I f action is not taken, flies may lay their eggs in the matted fur and the resulting maggots can eat away at the flesh of the rabbit leading

invariantly to death. Young rabbits are most frequently affected with coccidiosis just after weaning. The disease can develop very quickly and high mortalities are common. In older rabbits there may be chronic

coccidiosis resulting in dullness and poor growth.

Coccidiostats may be bought and added to the drinking water to prevent coccidiosis occuning or to cure it as required. Hutch cleanliness is an important preventive measure and wire floor, which allow the faeces to drop out of the hutch, are used

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to achieve a good level of sanitation, aimed at limiting coccidi­osis outbreaks.

Many other organisms can cause diarrhea as well as coc­cidia; so can irregular feeding and giving of over wet and soured food. At the first sign of any dian·hoea rabbits should only be offered dry forages and fresh clean water.

Diarrhea. The commonest sign of disease the rabbit farmer will come across

is diarrhoea. It should be noted that diarrhea in itself is not a disease but a sign of disease. Diarrhea is usually caused by the rabbit consuming the wrong food , such as sweet potatoes or the larvae of certain species ofbutterfly. When rabbit have diarThea, they become dull and begin to discharge watery green droppings. Some forms of diarrhea can kill a rabbit within twenty four (24) hours. Diarrhea can be prevented by providing the rabbits with

freshly cut and dried greens.

Other causes of intestinal problems Bloat. Specific feed factors can cause a lot of gas to be developed (bloat) or reduce the rabbit's resistance. The symptoms you notice are diahrrhoea, no appetite, listleness, loss of weight (check the to bones at the end ofback beside the spine), wet or dirty rear, blown up and or spongy feeling abdo­men. Not necessarily all of these symptoms show up clearly or at the same time. To determine other causes, you will need to do some simple laboratory analysis. Treatment include giving of good quality, drier feed to help rear­range the intestines. Treatment with sulfa medicine can be very

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helpful, especially as a preventive measure. Severely dehydrated (skinny) animals, as result of diarThoea, should be forced to drink by "injecting" water or milk in the mouth. The water should pref­erably contain some salt and sugar (9gram salt -L 9gram sugar per litre of water. A quantity of water of 10 - 20% ofbody weight gives you an idea of how much liqu id to give. Beside all these

consult your Veterinarian of Livestock Officer for advice . Prevention is almost the same for al l of the sub causes. Keep the animals away from their manure. Clean the stables every day. Do not give excessive wet feed . (note. however it is probably not the wet feed a lone causing the ·'enteriri complex". Rather, the in­tes tine gets so much disturbed by feed that is too wet that the disease agents have more opportuni ty to a ttack.) Give the ani­

mals good quality feed.

Worms. Rabbits may have worms. These are white and sometimes coiled. To de-wonn a rabbit, feed it paw - paw if available; the paw- paw plant is a natural de-wanner. The best remedy is to give the rab­bit, every four weeks or so dry paw- paw leaves or a mixture of a few mashed dried paw- paw seeds and grains. This will remove most of the wonns.

Problems of Respiratory tract Respiratory tract problems include coughs, sneezes, and pneu­

monia; they easily cause sudden deaths, which are difficult for

the layman to distinguish. Bacteria do not always cause them and medicinal cures are rarely successful.

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Signs Sneezing, coughing, dirty front legs (because they are used as a "handkerchief') noisy breathing, are indicators of respiratory problems. Not all cases die, some still live and reproduce as expected, but sometimes sudden death occurs among some cases.

Prevention Ensure fresh air, dust free and clean sun·oundings. Separate sneezing animals and slaughter them or sell them to butchers if you think that you have a good replacement. Besides some anti­biotic treatments, not much can be done other than prevention.

Ear and skin mange External parasites such as mites can cause a variety of skin and ear conditions. With ear mange the entire ear may become filled with crusty scabs without attention the mange may spread onto and over the face. All rabbits, and particularly their ears , should be regularly in­spected for mange and skin sores. Rabbits with ear mange may shake their heads a great deal. Acaricide drops and creams can easily control manges caused by mites. Body mange can be cured by dipping the rabbit in an appropriate acaticide solution as recommended by a Livestock or Veterinary Officer.

Ear Canker Small mites may burrow under the rabbit's skin, especially in the ears. The scabs must be removed with warm water and palm oil or Vaseline applied to the affected area. Also, pour some palm oil into the affected ear.

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Warbles It dirt is allowed to build up in and around rabbit hutches, the rabbits might develop warbles. Warbles is the result of eggs being laid in the fur of the rabbit, usually on its legs or feet, on the nose and around the eyes or on the fringes of the ear. When the eggs hatch tiny maggots' bun·ow under the skin to form a small lump under the fur of the rabbit. The rabbit may scratch the spot and this in tum might cause infection. Warbles have developed on the nose of the rabbit in figure 3 .. Warbles may also be effectively treated with palm oi I.

Colds When a rabbit has a cold, it sneeze and mucous will be discharged from its nostrils. Rabbits with colds should be isolated because the cold might develop into another illness which could spread to other rabbits and kill them.

Head Banging A strong rabb it which shows no symptom of any disease or illness may, without waming, run at tremendous speed into any obstacle in fi·ont of it, banging its head in the process. It will continue doing this until it dies. It is not known what causes this, or what the cure might be. Usually, by the time a veterinary officer gets to the frum the rabbit will have died.

Pests Dogs are the worst enemies of rabbits. If they get the slightest chance, they will, in short space of time, kill all the rabbits found in any one place. Always safeguard rabbits from dogs by keeping the dogs indoors or away from the hutch area and making sure that the rabbit hutches are strong enough to give the animals the protection they need.

Cats Wild cats and some domestic cats will molest rabbits. They will catch a young rabbit and eat only its nose, leaving the rest of the carcass in the coop. If properly made, hutches will keep cats out.

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Mice and Shrews Some nursing does are unable to drive away mice and shrews which enter the hutches and kindling boxes and eat the young rabbits. If mice and shrews are not destroyed, they wi II eventually eat all the young rab­bits. To prevent this from happening, traps can be placed outside the hutch. Altematively, poison can be used (rat poison is effective). When poison is being used, the fanner must provide water; after consuming the poison and drinking water, the mice or shrews die before they reach the rabbits. Always keep poisons on the ground near the hutches.

Snakes It is always possible that dangerous snakes such as cobras and puff adders may approach the hutches. lfthere are young rabbits, they are likely to be visited by a black cobra every 3-4 days. The snakes may swallow the rabbits whole. There are several effective ways of dealing with snakes. The first is to kill them, using hard boiled eggs as bait; the snake swallows the egg whole but its stomach cannot digest it, and the snake dies in the bush, away from the hutch. The second is to use 2cm-wire mesh when constructing the hutches. The third is to grow shallots or onions around or close to the hutches; the scent of shallots or onions will keep all types of snake away.

Fleas and Lice Some of the fleats that infest rabbits are similar to those found on dogs. They jump quickly from one spot to another. They suck blood and cause rabbits to lose fur. Fleas should be destroyed with Asuntol® 50, or simi­lar powders. One tablespoonful of either of these solutions will destroy fleas and lice on rabbits within a few hours. The rabbit is dipped into the solution or lightly washed with the liquid.

Other disease and health problems The most common problems are sore hocks (appears to be he­reditary) lame animals (variety of causes), injuries, sore breasts

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mastltts. Do not waste too much time waiting to see what will happen. Cull such animals. Beside being practical, you will save the animal a lot of suffering. In the long run you are selecting the bestand heaJ!hjestan:im aJs furyourbreedmg .

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PIGS Disease prevention. In pig husbandry, hygiene is of great importance. Once a disease affects a pig herd the impact on the economics of pig production in terms of the cost of control and decreased productivity can be enormous. The first priority must therefore always be to try to prevent the occurrence of diseases. Thus the pig farmer should be very familiar with the various management procedures aimed at disease prevention. With skilled management combined with well-designed housing and sound nutrition, an overall sn·ategy to minimize the possibility of disease attack can be formulated. At the same time, a basic knowledge of the main diseases which may affect a pig herd is necessary so that a producer can diag­nose the condition and implement control measures as quickly as possible.

Parasites Parasites are defined as organism, which lie on and ob­

tain food from the body of another, known as the host. They may live on the exterior of the pig, when they are known as external parasites, or within the internal tissues and organs when they are known as internal parasites. Parasites will seldom result in the death of the host except in the case of massive infestations or if the host is also stressed in other ways.

EXTERNAL PARASITES These mainly cause irritation to the skin surface, often leading to wounds and an increased susceptibility to other infections. The most common external parasites are mange-mites, ticks, lice, fleas and flies. Mange-mites Mites, which are scarcely visible to the naked eye, spend their

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entire life-cycle under the skin of the pig, but they can survive off the host for as long as eight days. The most common species is Sarcoptes scabiei which causes sarcoptic mange. First signs of infection are a crusty, dty -looking skin around the eyes, ears and snout. The mites spread and multiply over the body, and their bun·owing causes the skin to become inflamed and swollen. The pig will be seen to be constantly rubbing itself and performance is depressed. Control is best affected by regular treatment, ei­ther dipping or spraying with an anti-mange medication includ­ing spraying of pens. Chronically infected animals be culled.

Ticks Ticks are only a problem in scavenging or extensive systems of pig production. There are a number of different species, which suck blood and can transmit serious diseases (e.g. babesiosis or redwater). They generally require more than one host to com­plete their life cycle. Ticks are easily controlled by spraying or dipping with suitable acaticides.

Lice and fleas Both lice and fleas can become a problem in dirty unhygienic conditions, as they live on the skin surface, suck blood and cause irritation. Spraying of the pigs and pig quarters with suitable in­secticides are effective ways of controlling the pest. In the cause of! ice, particular attention should be paid to the ears.

Flies Flies have a major nuisance-value around pigs as they cause an­noyance, can bite and carry infection diseases. They are always attracted to any fresh abrasion or wound on the animal.

Control measures should involve spraying of insecticides on suitable fly-breeding areas, e.g. manure heaps, refuse areas and ponds, pig buildings and pigpens. Baits, which are, attract the flies and are poisonous to them but not the pigs can also beef-

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fective.

INTERNAL PARASITES Worms are one of the most serious threats to pig breeding. There are more than 30 types that can affect the intemal wall. The most impotiant are: the intestinal round wom1 (e.g. Ascaris /umbricoides) the lung worm (e.g Metastrongylus spp), kidney worm (e.g Stephannus dentatus) and the tape worm (e.g Taenia solium) Wonns are a particular hazard when pigs are free-ranging or not kept on concrete floors.

Round Worms The large roundworm (Ascaris lumbricoides) is very common and can cause a lot of damage in pig herds. Adults live in the small intestine and can grow up to 300mm long and 6mm thick (figure 2). The female is capable oflaying thousands of eggs per day, which pass out in the dung and become infective, if ingested by other pigs, after 21 days. These eggs are extremely resistant and can remain infective for many years . As part of the life cycle (figure 3) eggs hatch out in the pig after ingestion and the larvae migrate through the liver and lung. Irritation in the lungs causes coughing and ill-thrift, particularly in younger pigs. If infection is heavy the adult worm can partly obstruct the small intestine, causing weakness and loss of weight by the pigs. Contaminated feed and water are the usual source sof infection with internal parasites . Control can be effected by breaking the li fe-cyc le, which means regularly moving range pigs on a fresh ground and frequent cleaning and removal of faeces in housed pigs. Also routine dosing of pigs with broad-spectrum anthelmintics and

young stock dosed soon after weaning.

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Fig 3: Adult Ascarid worm in the small intestine

l ·tl t:! :.:Li· .. ·~ o: l :t-r

~;;;; ~; ::· 1!~~ n 11t

n r.,rr .. ~~

Fig 4 life cycle of the Ascarid worm

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Tapeworms The common tape worm is Taenia solium. The pig is its intermediate host and the adult work lives in men. Pigs be­come infected by pick­ing up eggs from human faeces and the larvae then encyst in the pigs muscle particularly in the region of the hea11 and tongue. If the pig meat (pork) is then eaten by man, the larvae hatch out and the cycle is completed. As a con­sequence carcasses, which are affected, are condemned at slaughter. This can be controlled by preventing pigs from having access to human faeces thus eliminating the parasite.

Fig 5: Life cycle of Tapeworm

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W.:k m 0: ~1 ~1:. form cy_..t~ itl plq rn~<ll .

INFECTIOUS DISEASES African swine fever. This is a highly contagious virus disease which in the acute form can cause 100 percent mortality. This illness starts with a rap­idly developing fever. Typical signs are loss of appetite, hur­dling together, small purplish blotches on the skin, incoordina­tion and laboured breathing, lies down a lot, is weak in the back legs. Sometimes the pig has runny eyes and nose discharge (sometimes with blood) and vomits. Often the skin is reddish ­blue (especially the legs). Bush pigs and warthogs are caniers of the virus but are immune to the disease, and it is therefore very imp011ant to prevent di­rect contact between domestic pigs and wild pigs through the control of an:im al m ovem e..nts. A roft tick (Ornithodoros moubata) which infects the wat1hog is a biological canier and therefore transmits the disease. Otherwise infection occurs by contact with other sick pigs or through contaminated food or water. There is no effective vaccine or treatment and infected pigs should be isolated from healthy ones.

Foot and mouth disease. This disease is generally regarded as the most contagious of all known viral diseases. This infection causes blisters on the feet, snout, udder and in the mouth and throat. It is very painful to the pigs, which cannot eat and often has to be destroyed. The dis­ease is endemic in parts of Africa and the virus is canied by the buffalo. Infection can occur by feeding infected bones or cooked meat. There is no cure. If an outbreak occurs in an adjacent area, pigs can be vaccinated, but as there are many strains of the virus it is important to ensure that vaccination is against the right vi­rus.

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Pneumonia This condition may be caused by bacteria, virus (usually by both at the same time) and parasites (lung worms and intestinal w01ms that have found their way to the lung). The condition is worsened by too many pigs in a small space, low temperature, draught, very low air humidity, dusty surroundings. The illness is more preva­lent in the rainy season. At this time the pigs should have dry and draught- free conditions. The animals cough especially after exeriion and when roused and breath wi th convulsions. \~lore­

over they are retarded in growth. If the condition is caused by

bacteria and viruses, then antibiotic is given. [fby lungwonn, anthelminthic is given.

Tetanus If a deep closed wound is caused, for example by standing on a rusty nail, then tetanus bacteria can develop. Animals become sick with tetanus 3-100 days after they get infected. The legs

become stiff and the animal moves stiffly animal become ner­vous, especially when something disturbs it. The muscles of the jaw and checks contract in spasm and the animal cannot eat or drink. After many days many muscles contract in spasms and the whole body becomes rigid. The third eye lid comes across the eye. The animal has difficulty breathing. After 5-7 days it usu­ally has convulsion cannot breathe and dies. Animal rarely re­covers from tetanus.

DISEASES THAT CAUSE FERTILITY DISORDER. Brucellos is Brucellosis is one of the diseases that cause fertility disorder. This disease is caused by bacterium which causes contagious

abortion in animals. An outbreak ofbrucellosis results in sudden abortion in pregnant sows, and it leads to temporary or perma-

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nent infet1ility. The sows may abort at any stage of the preg­nancy depending upon the time of exposure to infection with the bacterium. Some animals may become crippled (inflammation of the joints) and boars may develop inflammation of the tes­ticles (scrotum), with swelling and pains, permanent sterility may result. The disease is transmitted at mating or by contaminated food and water. There is no treatment for this and infected ani­mals should be culled, particularly as brucellosis is transmit­table to humans and the risk of transmission is high at under some traditional system of pig management. After a while, the disease may disappear spontaneously, but often comes back from time to time. Affected animals should be culled and the holding area should be cleaned and disinfected, and for at least two months, no pigs should be allowed in the holding yard. Prevention: an infected animal brought from outside is usually the cause. For example if the sow is mated elsewhere, the dis­ease can be brought in to the flock. For this, one should be very cautious when buying animals.

Weils diease (leptospiros is) The most important symptom of this disease is the aborting of many sows, usually towards the end of the pregnancy. Typical here is that the piglets are often different in size. They have died at various stages of the preg­nancy. Sometimes very weak piglets are born at the normal time. After the abortion the sows are normally fertile for their future life so that the disease dies out on its own accord within a few months. Having experi­ence the disease, the animals build up a resistance to it, and further repro­duction takes place normally. Such gilts should not be put aside. Hwnans can also get Leptospirosis.

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FEED RELATED DISEASES Anemia (blood deficiency) The cause is an iron deficiency in the mother's milk. This is especially common in young pigs. They become very pale a few weeks after birth and the growth slows down. This can be prevented bydailyputting iron rich soil, such as ditch mud, forestry soil or wood ash in the pen in which the pigs can root. This should be started in the first week. Very young pig can be given an injection ofiron-dextron.

Constipation

Animal with constipation do not pass faeces often. If the pig passes faeces , they are dry and hard. The pigs often strains to pass faeces. They sometimes get constipated when suddenly get different food or when pigs have a severe disease it often has constipation at first that changes to dian·hea later. It can also happen when an animal has a blockage in the intestine or when it has severe injuries of the back leg. Control: make sure the animal has plenty of water to drink, you can also give laxative such as liquid paraffin.

NON SPECIFIC DISEASES Abscesses Abscesses can occur as the result of any irritation, inflammation or wound which allows access to bacteria, normal strains of sta­phylococcus or streptococcus. The body of the pig reacts to the invasion of bacteria and a pocket of pus is waJJed off from the body. Abscesses are seen as swellings or lumps, often hot to the touch and they will in time develop a soft area, which can be lanced and drained. They may be superficial (fig 1) or they may form deep within the body, where they can cause lameness, in­terfere with breathing or swallowing, or may not be discovered

until slaughter. As abscesses are painful and can marked by depressed perfor-

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mance and reduced carcass value, every effort should be made to minimize the possible causes in piggery. Preventive measure include the removal of any objects (sharp or rough) from pig pens, ensuring the floors are not too rough, especially for baby pigs, making sure that injection equipment is steri lized and pro­viding overall good sanitation. Abscesses can be treated with antibiotics but this is not always effective

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Bibliography Bill Forse ( 1999), Where There Is No Vet. Macmillan Press Ltd. London and Oxford.

David H. Holness (199 1) Pigs. The Tropical Agriculturalist. .\t1acmillan Education Ltd, London and Basingstoke.

Denis Fielding ( 1991 ). Rabbits. The Tropical Agriculturalist. \1acmillan Education Ltd, London and Basingstoke.

Pond, W. G and .Maner, J. H. ( 1974) Swine production in temperate and tropical environments. W. H. Freeman and Co: San Francisco, USA

Radostits, 0 . M; Blood, D. C; and Gay, C. C. (1994) Veterinary .\t1edicine. Bailliere Tindal.

Schiere, J. B. (1990) Backyard Rabbit Farming in the Tropics . Agromisa, agrodok-series 1\r. 20

Stephen, 0 . A.() Try the Rabbit. A practicalguide. Published by CTA.53pp

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