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PART- III SHEEP AND GOAT PRODUCTION 1 SHEEP AND GOAT PRODUCTION Bakht Baidar Khan Arshad Iqbal Muhammad Iqbal Mustafa Department of Livestock Management University of Agriculture Faisalabad 2003 PART- III SHEEP AND GOAT PRODUCTION 2 FOREWORD The past more than half a century is a witness to the fact that except a few, no serious attempts have been made to write books even on a few of the so many wide open aspects of the field of animal sciences. Among other factors that keep the animal science sector lagging behind, utter lack of relevant books of local origin is probably the most important. The dearth of documented information concerning various species of our farm animals adversely affects the learning potential of our students, who have been reported to complain about the non-availability of professional books written in Pakistan. I personally feel that as animal scientists we cannot exonerate ourselves of this responsibility. Of course, not all of us would have the aptitude to write books. However, those who opt to take up this tiresome and time-consuming job, their efforts must be appreciated. We must not forget that beginnings are always small. It is really encouraging to learn that sheep and goats being the victims of a long neglect, have attracted the attention of experienced animal scientists and teachers of long standing to write a book on them. A look into the contents of the book ‘Sheep and Goat Production’, makes me believe that it would adequately serve the purpose for which it has been produced. Its made-easy format would be rather more helpful to the students, field workers and progressive farmers. A collection of over 650 questions along with their answers should more than suffice to cover the discussion on important topics in relation to sheep and goat production. Sajjad Zaheer Malik Director General (Ext.) L & DD Dept., Punjab PREFACE Innumerable publications on sheep and goat farming/production are there in the world market. More than 98% of them are of foreign origin and are thus either not available here or their prices are beyond the means of a common man. The book under discussion has not been produced to burden the market with another such publication rather it has been brought out employing a novice format to meet the requirements of beginners who venture to plan a small ruminant enterprise, but are found confronted with a series of questions. Answers to many of such questions are already embodied in this ‘easy to read and understand’ book. In addition, feasibilities in respect of keeping sheep and goats (pertaining to one breed of each spp.) have been outlined herein to facilitate the solution of their input: output dilemma. Another section of society most pertinent to books is professional students community. It often happens that even at the end of an academic session/semester, many students in a class, would not know what type of questions, relevant to a course, may be asked in the Exam. This book, for sure, would create an awareness in them as to the type of Exam. questions and as to the manner of answering them. Among other features of the book are: the discussion on behaviour and welfare of small ruminants and clues on the application of biotechnology in animals. A comprehensive review on terminology related to various aspects of small ruminants is also a part of this book. Most of the answers to the questions included in this book have been picked up as such from various sources of literature listed under references at the end. We feel highly obliged in sharing the fruit of hardwork of those so many authors/editors. Under the circumstances it does not seem possible for us to individually convey to them our grateful thanks, but indeed we remain indebted to all of them. No book will ever be complete and this one is no exception since knowledge about sheep and goats is increasing so rapidly that no book can be an absolute ultimate. We feel no hesitation to mention here that at places details of a few most sophisticated techniques used abroad in small ruminant production have been intentionally avoided simply because farmers/producers here have yet to go a long way to enable themselves to take full advantage of such costly tools and techniques. We would like to record our thanks to our colleagues, namely Drs. Muhammad Younas, Muhammad Abdullah, Muhammad Yaqoob, Syed Hassan Raza and Prof. William Hohenboken, a friend from USA; all of them provided us a lot of useful literature for this book. Special thanks are extended to Mr. Farooq Ahmed, Dr. Akhter Saeed and Dr. Asad Saeed for arranging recent literature for the purpose from abroad. Suggestions in black and white from any quarter to effect further improvement and to remove any omissions in the contents of this book will always be welcome. March, 2003 Bakht Baidar Khan Arshad Iqbal Muhammad Iqbal Mustafa PART- III SHEEP AND GOAT PRODUCTION 3 PART- III includes following contents of the book: • INTERNAL PARASITES IN SHEEP AND GOATS • EXTERNAL PARASITES • MEDICATION • HOOF CARE • RANGE SHEEP AND GOAT PRODUCTION • HOUSING AND HANDLING FACILITIES • DAIRY GOATS • MEAT • WOOL • MOHAIR PART- III SHEEP AND GOAT PRODUCTION 4 INTERNAL PARASITES IN SHEEP AND GOATS Q. In what way the internal parasites harm the sheep/goats? There are reports that indicate that sheep and goats are comparatively more resistant to bacterial and viral diseases, but more susceptible to internal parasites. Another report suggests that goats as compared to sheep are less prone to parasitic infestations. A weekend condition from parasite infestation can be a principal cause of a disease outbreak. A heavy load of parasites is a vicious cycle leading to undernourishment of the animals, making them further vulnerable to parasite damage. The highest death loss occurs in lambs/kids, yearlings and extremely old animals, with death loss higher in poorly fed animals. Internal parasites (Figure 19) reduce productivity, cause anaemia, bottle jaw, coughing, bronchitis, wool break, progressive weakness reduced milk yield and death. Q. Can sheep/goats develop some degree of immune resistance to worms? The development of a degree of resistance to worm loads in old animals results from constant exposure to migrating worm larvae over time because the larval proteins act as a form of vaccination against the larvae. This immunity is actually the development of antibodies that cause allergic reactions. A mini-allergic reaction occurs in the tissues surrounding the encysted worm larvae, in which a combination of smooth muscle contractions and fluids cause the parasites to be dislodged and expelled into the lumen of the intestine. Then they pass out with the faeces. This partial immunity to worms takes about two years to develop fully. This explains why older ewes/does do not accumulate as much worm burden as lambs/kids in the same pasture and younger animals must be dewormed more often than the older population. Q. Discuss briefly the life cycle of worms. For specific and detailed information about life cycles of various internal parasites, you are referred to a text book on Parasitology. Here the life cycle will be dealt in very general terms. More than twelve species of parasites are considered responsible for causing problems in sheep/goats. They live in true stomach, small and large intestines, lungs and liver where they feed on blood and body fluids, causing anaemia and serum loss. Millions of eggs from these parasites pass out with faeces, with cough and under favourable conditions of warm weather and moisture, hatch into infective larvae in about 5 to 7 days. These larvae migrate into the moist sections of the grass and are ingested more by sheep than goats (probably due to their habit of grazing close to ground surface). Once swallowed they invade the tissues of digestive tract etc. where they undergo a maturing stage and emerge as adult worms in about 21 days. Most of the eggs and/or larvae are killed under conditions of hot dry weather and severe cold temperatures, which largely helps sterilize the pasture. However, nature has provided a survival mechanism for these worms that allows them to survive periods of adverse conditions by hibernating as immature worms in tissues and then emerge weeks or months later when conditions for survival are more favourable. Q. Suggest measures that can help reduce parasite load of small ruminants. PART- III SHEEP AND GOAT PRODUCTION 5 Population density appears to be the main contributory factor for heavy parasite loads. A small number of animals on a given area will deposit less eggs than a large number on the same area. By rotating animals from one pasture to another, you can allow time for worm larvae to die from age and exposure on the recently contaminated grass. The eggs/larvae of many stomach worms can survive three months in cool damp weather but much less in dry hot weather. An old Scottish rule of thumb is ‘Never let the church bell strike thrice on the same pasture’. Overstocking of pastures cuts down the feed supply which weakens the animals. It also causes them to graze the grass more closely, ingesting more larvae to increase their worm load. Animals in poor nutritional condition cannot tolerate as much worm load as well nourished can. Lack of proper diet, insufficient protein and incorrect balance of nutritional elements, including vitamins and minerals (such as Se), makes them more vulnerable to worm damage. Another step toward better parasite control is sanitation. Never put feed directly on the ground to avoid contamination. Make sure that the water supply is clean and protected from faecal contamination. It is necessary to be able to recognize symptoms of worm build up and carry out an adequate control programme using appropriate medicines. Q. What are the more appropriate time periods for deworming sheep/goats? With the development of safer and more effective deworming drugs, deworming can be carried out without harming ewes/does or their youngones. Ewes and may be does too should be dewormed at the beginning of the flushing period i.e. two to three weeks before breeding. With higher parasite loads they will not settle properly and will have protracted lambing/kidding period. They will produce fewer twins and more weak newborns and will have less milk for them. Pregnant animals with more worms are drained of needed energy. Their weakness leaves them more susceptible to pneumonia or pregnancy disease and too weak to withstand a difficult delivery. Post parturition rise in parasite load also takes place, which is due to hormonal changes that trigger the encysted larvae to wake up and complete their life cycle. A similar rise in worm burden also occurs in breeding male, more so in ram than buck, as spring approaches. This refers to the worm’s survival mechanism already mentioned in a foregoing question/answer. Therefore, deworming at three weeks postparturition is advisable. It helps save the ewe/doe energy for milk production which otherwise could have been wasted by worms. In climates where worm infestations can occur during gestation, it may be necessary to deworm two to three weeks prior to lambing/kidding. However, at this late stage handle the pregnant animals carefully since the stress of catching and deworming may trigger some problem. Levamisole or Ivomec is good for this late pregnancy deworming, because they have some effect against hypobiotic (arrested) and migrating larvae. Other vermifuges kill only the adult forms, allowing the migrating larvae to become active the day following deworming. For the most part, deworming medicines have no residual activity. They are only good the day you give them. Next day the immature larvae are free to build up the worm burden all over again. In most small ruminant-rearing areas, the worm population is severely depressed during severe winter months. This then means that about 90% of the parasite population is in the sheep/goat with 10% on the pasture. When these animals gain access to the pasture during favoruable weather, the ratio reverses. Thus the most suitable time to exhaust the new season’s worm population is to reduce it as much as possible in the sheep/goats prior to grazing season so that these animals cannot transfer or seed the population back to the PART- III SHEEP AND GOAT PRODUCTION 6 pasture. The animals should be dewormed three days before turning them out on pasture so that the worm eggs excreted in the faeces can fall outside the barn where the larvae cannot survive. In areas where the grass begins to dry, deworming the animals at that time, then followed up with another deworming six weeks later, will reduce the worm load below harmful levels. The hot dry weather significantly reduces the larvae population in the pasture, thus reducing the infection rate in the animals. It is also helpful to move animals to a clean pasture 24 to 48 hours after deworming, to keep the pasture clean. Young lambs/kids sent to pasture with their dams pick up worms that will grow to maturity in about a month. As the worms increase they cause anaemia and even death. You can prevent anaemia by deworming the lambs/kids at about 2½ to 3 months of age. When rotating pastures, let the lambs/kids graze each clean pasture ahead of the ewes/does. Q. Suggest an economical parasite reduction mixture. An economical and popular mixture is 6 kg trace mineralized salt, 3 kg dicalcium phosphate and 1 kg phenothiazine. This low-level feeding of phenothiazine keeps worm eggs from developing properly. The killing of eggs and larvae cuts down on the source of parasite infection on the pasture. No immediate results will be seen, as it does not affect the eggs and larvae on the pasture. However, over a period of time there will be fewer worm larvae on the pasture to reinfect the animals. Q. What symptoms are commonly observed as a result of parasite infestation in small ruminants. One visible sign of parasite infestation is bottle jaw (swelling under the jaw). It is a sort warning that the animals have severe attack of worms. Other symptoms are diarrhoea (for some kind of worms) and anaemia (for most kinds of worms). Anaemia is indicated by the very pale colour of the inner lower eyelids and gums caused by intestinal worms sucking the animal’s blood. There are eight or more kinds of small stomach worms (round worms) that cause anaemia but not diarrhoea. The animals become listless, with pale mucous membranes and lose condition, wasting away and dying if they are not dewormed. The small brownish stomach worm ‘ostertagia’ causes scours. It is so perfectly camouflaged against the walls of sheep’s small intestine that it is difficult to spot in a postmortem. Other symptoms are accelerated breathing, coughing, and discharge from nose, bronchitis and pneumonia caused by lungworms. Liver flukes may cause bottle jaw, pot-belly etc. Q. In what different forms deworming drugs may be administered to small ruminants? Most infestations involve more than one kind of parasites, the broad-spectrum deworming drugs are recommended for general deworming. One of the several major broad-spectrum, low-toxicity vermifuges will take care of the most prevalent of the stomach parasites. For dosage and method of administration (as well as withdrawal days before slaughter) follow label directions. Deworming drugs are given as: boluses, these are sort of large⎯ sized pills, may be given by hand, by a bolus gun or with a capsule forceps; drenches, these are given by a drenching gun if the flock is of large size, for a small flock use a handy 2-ounce dose syringe; powders or granules, these are mixed with salt and dicalcium phosphate and offered to the animals free choice; premixes, these are given PART- III SHEEP AND GOAT PRODUCTION 7 mixed in feed; paste, this can be smeared on the animal’s tongue; injection, be sure to follow label directions as to the site for injection, type of injection and the dosage as given for sheep/goat weight. Q. Give a list of the deworming drugs (for sheep and goats) that are in common use the world over. It cannot be a complete list since recent and new drugs keep on coming in the market, at the same time the use of certain drugs is abandoned in certain countries. Drugs under different brand names are also locally produced. The list given below includes such drugs that have been found safe, effective and easily available in the market: • Tramisol (Levamisole): Effective against three species of stomach worms, six species of intestinal worms and a lung worm, safe for pregnant animals (after first 30 days), for older lambs/kids as well. Marketed as oblets (bigger pills), drench or injection. • Thiabendazole (TBZ) (Omnizole R): For stomach, small and large intestine worms, sold as bolus, paste, drench or feed additive. • Phenothiazine: Now not considered a standard treatment. However, pheno is excellent for continuous low-level use, mixed into your salt formula. • Ivomec (Ivermectin): Sold as injection or drench, effective against stomach, small and large intestine and lung worms, blood-sucking lice and keds (ticks), not effective against tapeworms. • Fenbenzadole (panacur, safegard): Safe and effective against stomach, small and large intestine worms, lungworms and tapeworms. • Equipar (Oxibendazole): The same as Fenbenzadole but does not kill tapeworms. • Telmin (Mebendazole): Effective against stomach, small and large intestine worms, some effect on tapeworms and liver flukes. • Curatrem (Clorsulon): Excellent for developing and adult flukes, if liver much damaged then recovery not complete. • Rumatel (Moratel tartret): Effective for small and large intestine worms as well as stomach worms. • Bovatec (Lasalocid): For prevention of coccidiosis. • Deccox (Decoquinate): Prevents coccidiosis, used in free-fed salt/mineral mixture. Q. Write a note each on lungworm and tapeworm infestation in sheep/goats. Lungworms: These are prevalent in low-lying or wet pastures and live in air passages of small ruminants causing accelerated breathing, coughing and sometimes a discharge from the nose. The coughing can precipitate prolapse during pregnancy. The small lungworm (hair lungworm) can cause pneumonia and bronchitis. Good nutrition helps build up resistance to the worm. Keep the animals away from ponds and wet areas where snails can be found as several species of snails and slugs act as intermediate hosts for the lungworms. When an infected animal coughs, eggs are expelled and eaten from the grass by other animals. This problem needs consideration when buying sheep/goats from a farm or an area having low-lying pastures. Tramisol given once a year should control lungworms. Ivomec and Fenbenzadole are also effective. PART- III SHEEP AND GOAT PRODUCTION 8 Tapeworms: The feeding head of the tapeworm injures the intestine and is thought to facilitate absorption of toxin involved in enterotoxaemia. Tapeworms are not usually the primary worm infestation in small ruminants, but since the passed tapeworm segments are large enough, their presence in droppings becomes alarming. A moderate level of tapeworms is said to be of little damage to adult animals but can seriously retard the growth of youngones. Fenbenzadole (Panacur, Safegard) is effective against tapeworms. Q. Write a note on each of the three: Nose bots, Liver flukes and Coccidiosis in small ruminants. Nose Bots: The nose bot, Oestrus ovis, is a fly in its mature form, dark grey about the size of a bee. The full grown larvae are thick yellowish white grubs about 2.5 cm with dark transverse bands and found primarily in the frontal sinuses of sheep. When deposited by the fly on the edge of the nostril, the grub is about 2 mm and gradually moves up the nasal passages. During fly season, sheep will put their heads to ground, stamp and run with heads down to avoid fly. They press their noses to the ground or against other sheep, as the flies attack them. This is more observed in the heat of the day and in hot summer. The head grubs cause irritation in nostrils, sinuses resulting in inflammation which causes a thin and then a thick secretion. The mucous membranes are affected and the secretions thicken, the sheep thus have difficult breathing and may sneeze frequently. They become run-down because of being so much annoyed by flies that they cannot graze in peace. Ivomec R has but a slow effect on nose bots, taking about thirty days before they are all dead, decamped and sneezed out. Liver Flukes: They require an intermediate host i.e. part of their life cycle is spent in another creature. In case of flukes it is snail or slug, found on wet marshy land. Ponds, ditches or swampy land provide the breeding place for the snails. Therefore, this kind of pasture is not suitable for small ruminants. If possible drain out wet areas where snails propagate or put fence around marshy parts. Snail-destroying chemicals can be used if these do not harm fish, other livestock or human beings. A mixture containing 1 kg copper sulphate with 4 kg of sand can give good control of flukes. About 350 g of this mixture may be applied twice a month per hectare of pasture. Liver flukes cause bottle jaw or pot-belly during early stages, followed by loss of condition, diarrhoea, further, weakness and death. It can be diagnosed by microscopic examination of faeces and from the liver of slaughtered small ruminants. Affected livers must be discarded. Merck’s curatrem (clorsulon) kills developing flukes as well as adults and is especially useful for animals treated in early stages of infestation. Coccidiosis: Coccidia are microscopic protozoan parasites, present in most flocks without causing any serious problem. Overcrowding and contamination of food and water are the main sources of infection. Other factors are chilling, heat stress, transportation fatigue and sudden change in feed as well as interruption of feeding which predispose the young stock to an outbreak of coccidiosis, resulting in diarrhoea, then diarrhoea with straining, chronic dark green or bloody diarrhoea, loss of appetite and some deaths. Lambs/kids that recover are usually considered immune. A routine faecal examination showing evidence of this parasite will allow you to use appropriate drug at an early stage. Once coccidiosis is diagnosed (or be before as a preventive), Bovatec may be used as a feed additive. Antibiotics can be given to check any secondary bacterial infection in intestines damaged by coccida. Amprolium 1.25% can be prescribed and fed for 21 days during an attack. Meat fed to dogs and cats that associate with livestock should be PART- III SHEEP AND GOAT PRODUCTION 9 previously cooked or frozen to render these parasites (in muscle tissue of cattle, sheep or goat) noninfectious. Q. Discuss worm resistance to drugs used for deworming. The problem of parasite control has somewhat been compounded by the development of resistance in selected worm species to some worm-control products. All populations of living things contain individuals that naturally possess a greater resistance to something than the average population. Possible dewormer resistance increases with the frequency of treatment because we keep killing off the susceptible worms and leaving the possible resistant ones to regenerate the population. Keep in mind that if you must deworm very frequently, you are increasing selection pressure on the worm population and resistance may become a problem sooner for you than for your neighbour who needs to deworm less often. The old recommendation to change dewormer drugs often to avoid developing resistance is wrong. It is now recommended to use the same vermifuge until you see resistance becoming a problem, then switch to another dewormer. If you must change a vermifuge, do not alternate with a dewormer of the same chemical family or class. Resistance usually develops on chemical class lines, not brand names. Read the fine print for the generic name or chemical class. The more effective a dewormer is on several different species (broad-spectrum), the less chance of selection for resistant strains. Do not underdose the dewormer, because natural resistance is rarely an all-or-none phenomenon; it is a dose-related thing. By underdosing you may allow a marginally resistant worm to survive and propagate offspring with greater natural resistance, when it might have been susceptible to the full dose. With a highly effective drug, the worm numbers become so depleted that they lack the genetic variability required for selection for resistance in a short time. To know for sure whether you have worm resistance to the drug you are using, you need egg counts. If egg counts are taken just before and then one week after administration of the correct dose, and the percentage decrease in the egg count is les than 80%, the presence of anthalmintic-resistant parasites must be strongly suspected. To avoid introducing resistant strains, you would need to treat all incoming new animals. PART- III SHEEP AND GOAT PRODUCTION 10 [...]... lice and are safe to use 13 PART- III SHEEP AND GOAT PRODUCTION MEDICATION Q From a flock of 80 sheep/ goats, how would you detect a sick sheep/ goat? Successful treatment of any sheep/ goat illness requires detection as early as possible, before the animal is down Gone are the days when it was said that “a down sheep is a dead sheep , but the chance for recovery is much better if illness is diagnosed and. .. slowly and have good light so that you can see what you are doing Flatten and finish 27 PART- III SHEEP AND GOAT PRODUCTION the hoof with the rasp or file Trim the hooves of a doe early in pregnancy and preferably do not do it again till after parturition Be sure your buck’s hooves are well trimmed prior to the breeding season Q Write a note on mortality in sheep 28 PART- III SHEEP AND GOAT PRODUCTION. .. like mayonnaise it indicates pseudopeumonia The wound should be treated with acryflavine or tincture of iodine Some reports suggested that goat flocks vaccinated for corynebacteria became abscess free 22 PART- III SHEEP AND GOAT PRODUCTION 23 PART- III SHEEP AND GOAT PRODUCTION HOOF CARE Q What are the various causes of lameness in small ruminants? Suggest preventive measures in this regard The possible... predispose the sheep/ goats to a number of parasitic diseases • Newly acquired animals can be carriers of many serious diseases such as foot rot and brucellosis as well as ticks and lice • Venereal transmission of disease at breeding time • Dirty hypodermic syringes and needles can cause injection site infections and abscesses and transmit certain infectious diseases 14 PART- III SHEEP AND GOAT PRODUCTION. .. type of operation, the purchase of new animals and the conditions under which the animals are being raised Q Name some of the most useful immunizing agents for small ruminants that are in use in New Zealand, Australia, Canada and USA • Nasalgen-IP (P13): To protect against certain types of pneumonia and respiratory diseases 19 PART- III SHEEP AND GOAT PRODUCTION • Footvax: Foot rot vaccine This product... protection of sheep/ goats and youngones against white muscle disease and immune deficiency It is mainly required in selenium deficient area Too much of it is highly toxic Q Give schedule for vaccination of sheep/ goats against various diseases Tentative vaccination schedule Month Week Sheep Goats nd January 2 Enterotoxaemia Enterotoxaemia February Ist Anthrax Anthrax March Ist Sheep pox Goat pox April... sterilized and chilled After reconstitution, the inoculum must be kept cool and used within 2 hours 20 PART- III SHEEP AND GOAT PRODUCTION • • Instructions given on the label must be strictly adhered to Empty ampoules/vials and left-over inoculum should be properly disposed off Q What do you know about ovine progressive pneumonia (OPP)? Explain in detail Any chronic ailment can result in thin sheep but.. .PART- III SHEEP AND GOAT PRODUCTION EXTERNAL PARASITES Among the external parasites are included ticks, wool maggots (fleeceworms), common scab mite, lice etc Q Are sheep ticks real ticks? Give a brief account of them and discuss measures for their eradication No! Sheep tick is not a real tick rather it is a wingless parasitic fly, known as a sheep ked that passes its whole... accumulation of manure and formation of muddy areas; and having footbath arrangement for use when needed Q What do you know about foot gland? Explain Sheep have a deep gland between the two toes of each foot, with a small opening at the front and top of the hoof It can be readily seen Goats do not have these The gland’s secretion is waxy and has a faint, strange odour, said to scent the grass and reinforce... true abscess and occurs within the hoof structure, usually affects only one foot It is considered infectious, but not extremely contagious like foot rot The infection causes formation of thick pus and as the internal pressure increases, the animal becomes more and more lame Sometimes, there is a 24 PART- III SHEEP AND GOAT PRODUCTION swelling above the hoof It is caused by bacteria in manure and dirt, . need to treat all incoming new animals. PART- III SHEEP AND GOAT PRODUCTION 10 PART- III SHEEP AND GOAT PRODUCTION 11 EXTERNAL PARASITES Among. RANGE SHEEP AND GOAT PRODUCTION • HOUSING AND HANDLING FACILITIES • DAIRY GOATS • MEAT • WOOL • MOHAIR PART- III SHEEP AND