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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

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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

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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

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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.

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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

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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

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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

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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

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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

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PART- III SHEEP AND GOAT PRODUCTION

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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 life cycle on the body of the sheep. It lays little brown pupae, which

hatch into almost mature keds in about nineteen days. Ticks are bloodsuckers and roam

all over the sheep, puncturing the skin to obtain their food. As a result firm dark nodules

develop, damaging the sheep skin and thus reducing its value. These defects are called

‘cockles’ by leather traders. The ticks produce such irritation that sheep rub and scratch

and injure their wool and bite at themselves to relieve there suffering, sometimes

becoming habitual wool chewers. From eating the wool they may get impacted rumens.

Ticks reduce weight gain and cause anaemia. All this ultimately impairs the quality and

yield of wool and meat. Ticks stain the wool with their faeces. Such wool is sometimes

referred to as ‘dingy’ and does not readily scour out.

With systematic treatment ticks can be easily eradicated. The mature tick lays a single

puparia a week and thus a total of about a dozen or so in her lifetime. The pupa shells are

attached to the wool nearly 1½ to 2½ cm from the skin. Thus most of them are removed

in shearing, making it easy to eliminate ticks by treating after shearing. The newly

hatched ticks die within an hour unless they can suck blood from a sheep. The mature

tick cannot survive more than two to four days away from the sheep. To be effective, all

sheep must be treated for ticks at one time; otherwise the untreated ones will pass the

ticks back to the treated. Examine a new lamb or sheep before turning it in with your own

and treat it if you find even a single tick. Following are the methods commonly used for

treating sheep to eliminate ticks from their bodies.

Dip: This is a standard method used with large flocks. The sheep are run through large

dipping vats full of sheep dipping liquid or through spraying vats, where they are given a

high-powered spray from several sides at once. This is done usually ten days after

shearing while the wool is still short and the shearing injuries have healed. For a small

flock this method is not practicable. Their deticking requires small dipping vats or some

other method such as spray or sprinkle may be used (details of dipping to be discussed

elsewhere).

Spray or Sprinkle: Low-pressure sprays are ideal for treating sheep when they have

been sheared recently as stated under dip method.

Sprinkling with insecticide solution in a garden sprinkler can, requires very little

equipment.

Injection: Ivomec (Ivermectin) dewormer is effective against most internal and external

parasites including ticks. It is not effective against tapeworms, flukes or biting lice.

PART- III SHEEP AND GOAT PRODUCTION

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Q. Give a list of effective sheep ked control chemicals along with brief

instructions for their use.

Ectrin, Expar, Atroban: These are synthetic pyrethroids (a stable form of the garden

insecticide made from the chrysanthemum). They are considered both safe and effective.

Used for both ked and lice control as a pour-on or spray. No label withdrawal period

prior to slaughter.

Ivomec: This is effective against keds (ticks) and sucking lice. Consult label for

withdrawal times.

Co-Ral (Coumaphos): A systemic organophosphate. Used as a 0.6% spray or dip, or a

0.5% dust (1 to 2 ounces per sheep). Not to be used on lambs under three months of age.

Diazinon: Used as a 0.5% spray or dip. Not to be used on lambs under one month age.

Rotenone: It is the powdered root of a tropical plant and an insecticide used by organic

gardeners. For dip use 8 ounces of the 5% wettable powder to 100 gallons of water (1½

ounces in 20 gallon can). Mix it to a paste in a small amount of water and add it to the

large quantity of water in the can stirring well. The addition of a small amount of liquid

dishwashing detergent will make it more penetrating and effective. Safe for ewes and

lambs. For dusting use 1.5% (garden type) dust about 2 ounces per sheep. The effect of

Rotenone is not immediate. It takes a few hours to show its effect. Ticks no longer can

bite and will die.

Official regulations on chemicals can change from year to year, as new chemicals are

approved, some old may be banned or tolerances change. The concerned agency may be

consulted for a current list of such products.

Q. Give a brief account of wool maggots (fleeceworms) and suggest measures to

prevent them.

Several types of blowflies lay maggot eggs and they all are about twice the size of

houseflies. They appear in spring and then reproduce through hot weather, laying their

eggs in masses at the edge of a wound or in manure-soiled fleeces. The eggs hatch in six

to twelve hours and the larvae feed on the live flesh at the edge of the wound. They

enlarge the wound and if not detected, can eventually kill the animal. Watch for moist

fleece areas or any injury that may become infested. Notice if animals scratch excessively

on fences, trees, and gateposts. This could be maggots or ticks. When you locate an

infestation, clip the wool around it and spray it with any of the fly-strike aerosol sprays

(or one of the sheep tick chemicals can substitute for fly repellent). If none of these is

available, pick out all the maggots you can see and disinfect the wound. The animal

should be kept under observation for a few days and may be treated again if needed.

Shearing the sheep would make it easier to spot other infestations. Maggots often infest

dog bites if your sheep are chased by dogs, check them often for unnoticed wounds and

fly-strikes. The wool maggot or fleeceworm can be distinguished from the more

dangerous screwworm. Wool maggots can move and crawl around, while the

screwworms do not, since they are imbedded in the flesh.

Prevention Measures :1) Keep rear ends of ewes regularly tagged, especially when

droppings become loose. Deworm your sheep regularly. Urine also attracts blowflies if it

soils heavy tags; 2) Treat all cuts or shearing injuries with fly repellents during hot

weather, even insect bites invite flies; 3) Put fly repellent on castration sites on lambs in

warm weather; 4) Possibly use fly traps or other means to cut down the number of flies in

the barn; 5) Be especially vigilant during prolonged wet weather in summer. Warm and

PART- III SHEEP AND GOAT PRODUCTION

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moist conditions more favourable for fly strike. If by chance whole of the flock has

maggot problem, use Atroban or Expar- the sheep dip chemicals on all of them.

Q. Write a note on each of the two, i) common scab mite and ii) lice.

Common Scab Mite: Several kinds of parasitic mites produce scab in sheep. The

Psoroptes ovis is the common scab mite, a little more than ½ mm long, with four pairs of

brownish legs and sharp pointed brownish mouthparts. The mites puncture the skin and

live on the blood serum. The skin becomes inflamed, then scabby with a grey scaly crust.

The wool falls out, leaving large bare areas. This may not be confused with the loss of

wool that sometimes occurs along the backbone of some breeds of sheep when kept in

areas of heavy rainfall. To determine whether mites are present, scrape the other edge of

one of the scabs (mites seek the healthy skin at the edge of the lesions) and put the

scrapings on a piece of black paper. In a warm room under bright light, examine the

paper with a magnifying glass. The mites become more active when warm and are visible

under the glass. Any infestation with common scab mite (often called mange mite) is

very susceptible to Expar, Atroban or Ectrin. These are effective as a spray and can even

be used on pregnant ewes. All sheep must be treated in one session since the mite is quite

contagious from sheep to sheep. Infected premises should not be used for clean sheep for

thirty days.

Lice: These are probably second to ticks (keds) among the common ectoparasites

affecting sheep and goats. One species of biting lice and several species of sucking lice

affect small ruminants. The eggs are attached to the individual wool/hair fibres and hatch

in one to two weeks into the nymph stage. After several molts which require another two

to three weeks, the nymphs emerge as adults. The feeding lice (sucking) cause intense

irritation and itching to the sheep/goats which results in restlessness, constant scratching

and rubbing against walls, trees, fences, interrupted feeding, loss of weight and severe

damage to wool/hair. A clear-cut sign of lice in the flock are hundreds of telltale tags of

wools hanging from fences, trees etc. where the sheep have been rubbing. Lice are very

susceptible to the commonly used insecticides but often two treatments are needed to kill

any newly emerged nymphs (as the egg is a protected stage). Once removed from the

flock, they will not return until you introduce new/more infested animals into the flock. If

in doubt, you must treat any new animals prior to placing with your flock. The pyrethroid

products such as Atroban, Ectrin, Expar, do an excellent job of ridding the flock of lice

and are safe to use.

PART- III SHEEP AND GOAT PRODUCTION

14

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 treated

before it has progressed. Prevention is always better than treatment and early treatment

has better success than late.

For early detection of a sick animal you must be familiar with its normal behaviour, even

for each individual in the flock, to know when one is acting abnormally. Have some

quick and easy way of catching the animal (such as a corral) when needed for its close

examination. Signs of abnormality are loss of appetite, not eating as usual and standing

away from the group when at rest; unusual discharge from nostrils, eyes or mouth. Be

concerned if a sheep/goat is lying down most of the time when others are not; any

weakness or staggering gait; unusually laboured or fast breathing; change in bowel

movements (loose faeces or constipated); temperature over 104 degrees. Normal

temperature of small ruminants (except in very hot weather) is in the range of 100.9 to

103.0°F degrees (average 102.3 degrees). If it is necessary to have a urine sample, try to

hold the sheep’s/goat’s nostrils closed for a moment; this stress sometimes triggers

urination.

Q. In general, what may be the possible causes of illness of sheep/goats?

Some of the common causes of illness are: Unsanitary housing, lack of exercise, moldy

or spoiled feeds, poisonous plants, toxic substances improper diet (insufficient/

contaminated water and feed or overeating), parasites, injuries, infection from assisted

lambing/kidding, bacterial infection from other sick sheep/goats, abrupt change of feed,

stress due to severe weather, transportation, predators etc. and infection from newly

purchased animals.

Q. Give a list of common sources of germ transmission to sheep/goats.

• Water or feed contaminated by faeces from small ruminants or other animals,

can transmit intestinal diseases and certain parasites. Respiratory disease may

also be spread by nasal discharge into drinking water and feeding troughs.

• Manure accumulated in a lambing/kidding shed or around the feeding trough

can intensify exposure to disease germs and coccidiosis; serve as breeding

media for flies and other vermin.

• Dirty uncrotched wool on an ewe can infect the newborn.

• Feeding on bare ground greatly contributes to disease and parasite exposure.

• Wet muddy places predispose the sheep/goats to hoof diseases.

• Low-lying marshy areas 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.

PART- III SHEEP AND GOAT PRODUCTION

15

Q. To meet emergencies in respect of small ruminants farm/in field, what

medicines and equipment need to be on hand?

It may be referred to as a First Aid Kit. It should at least include bloat medication (and

trocar cannula for extreme emergency), cal-phos or any other preparation for milk fever,

propylene glycol for pregnancy toxaemia, tincture iodine and other disinfectants, mineral

oil for constipation, dextrose solution, antibiotics, uterine boluses and some sterile

equipment (syringes, needles etc.). Of the antibiotics pen-strep (Penicillin￾dihydrostreptomycin) (or any other recent one) will check many infections. For specific

infections, other antibiotics are necessary. Penicillin and tetracycline are safe to use since

their toxicity in sheep/goats is extremely low. These drugs are of use in pneumonia,

infection after parturition and as a preventive against infection following cleaning and

dressing of maggot infestation. These are of minor help for enterotoxaemia. Certain drugs

labeled for buffalo/cattle can be used for small ruminants in an emergent situation. Such a

drug can be administered at the same dose level on per kg body weight basis. On average,

the dose for one buffalo/cow would suffice for five to six adult sheep/goats. However,

with many drugs exact dosage is very important. Help of a competent veterinarian may

preferably be sought.

Q. Give a list of methods used for administering medicines, vaccines etc.

Oral, by mouth such as boluses for deworming with bolus gun or capsule forceps. Oral,

powder such as vitamins, placed well back on the tongue for treatment of an individual

animal, or in feed or drinking water for general treatment of whole flock. Oral, liquid

given as drench with syringe or in drinking water. Spray-on, such as insecticides for

ticks. Pour-on, such as tincture of iodine on newborn navel, disinfectant on minor

wounds. Subcutaneous, medication injected just under the skin. Intradermal, medication

injected into the skin. Intramuscular, liquid such as antibiotics injected into heavy

muscle. Pessaries, as uterine boluses to prevent infection after a difficult

lambing/kidding. Intramammary, injection of fluid or ointment through the teat opening,

as mastitis drugs. Intraperitoneal, injection of liquid through right flank into the

abdominal cavity. Intraruminal, injection of fluid into the rumen, on the left side, as for

bloat treatment when too late to give by mouth. Intranasal, spraying of vaccine into the

nasal cavity. Intravenous, injection of fluid into a vein. Intraperitoneal, intraruminal and

intravenous medication should preferably be given by a veterinarian or by an experienced

person.

Q. Give some details of administering drugs etc. by oral method.

Boluses (small or large pills) meant for small ruminants will go down the throat easier if

coated with mineral oil or cooking oil or mustard oil. Do not soak them otherwise they

will disintegrate. The easiest way to hold the sheep/goat is to back it into a corner and

straddle it, facing forward. Hold the bolus in a bolus applicator/balling gun (Figure 20)

and eject it when you have the pill over the hump of the tongue. Capsule forceps can be

used to deposit the bolus at the base of the tongue. However, forceps is more likely to

damage the throat. Forceful jamming of the bolus too deep into the throat can cause the

bolus to be deposited into the windpipe (trachea) with fatal results. Keep the mouth of the

animal open by inserting your left thumb in the mouth in the space between the front

teeth (incisors) and the molars, while gently inserting the bolus gun with the other hand.

Do not release the animal until you are sure that the medication has been swallowed.