Health Management

Common Diseases of Sheep and Goat

Blue tongue (BT)

Causes

• It is caused by Arthropod-borne orbi virus in the family of Reoviridae.
• Biting insect of the genus of the Culicoides transmits the virus during the rainy season while blood sucking.
• Mosquitoes and other ectoparasites like sheep ked, Melophagus ovinus may transmit the disease mechanically.
• The disease is more prevalent in late summer and early autumn which makes conducive environment for the multiplication of the vectors.
• Transmission through semen and placental route is possible.
• The virus is resistant to decomposition, desiccation and against antiseptic agents.

Clinical symptoms

• Fever
• Depressed attitude and off feed.
• Reddening and swelling of nose and oral mucosa,
• Profuse nasal and oral discharge,
• Inflammation and ulceration of lips, gums,  buccal mucosa and tongue,
• Cyanotic (bluish) appearance of tongue,
• Tilting of neck towards one side (wry neck)
• Lameness, reddening and swelling of coronary band of the limbs.
• Congestion of conjunctival mucous membranes and matting of eyelids,
• Foul smelling diarrhoea.
• Dyspnoea, snoring and Pneumonia may be observed.
• Death due to respiratory failure.

Suggested first aid

• Separation of sick animals should be made.
• Affected animals should be kept away from solar exposure.
• Adequate rest to the affected animal.
• Affected animals should be fed with porridge made of rice, ragi and kambu.
• Apply glycerin or animal fat on the ulcers.
• Immediate consultation should be made to the nearest qualified veterinary
• doctor for treatment.
• Animals should not be allowed for grazing.
• Ulcers in the mouth can be treated with saline water or dissolve 1g of
• Potassium permanganate in 1 liter of water and wash the mouth 2 to 3 times a
• day with this solution.
• Contact your nearest Veterinary Assistant Surgeons for further advice regarding the antibiotic administration or symptomatic treatment to be given to the affected sheep.
• Contact nearest Veterinary Assistant Surgeons for ring vaccination in the event of outbreak of disease.

General prevention and control measures

• Proper Vaccination of animals with regular intervals.
• Vaccination schedule:

• Attempt should be made to control the vector (culicoides) population with fly repellants.
• Use of ectoparasiticides injections should be suggested in the areas more prone to vector population.
• Grazing of the animals should be avoided in areas where there is lot of vectors.
• Cattle may act as carrier. Viraemic stage remains in them for more than 5 weeks. So movements of cattle should be restricted.
• Importation of animals from the areas prevailing the disease should be avoided.
• Strict regulation is to be followed to prevent entry of diseased animals from endemic zones.
• The spread of the disease can be controlled by the use of insect repellents, external application of fly repellents and spraying of butox (1ml in 1 liter of water) in the breeding places of the insects.
• The sheep can be housed in insect proof sheds.
• Cloud of smoke with dried leaves / wood during 6 - 8 P.M. might help to keep off Culicoides from sheep sheds.

Peste-des-Petits Ruminants (PPR)

Peste des petits Ruminants (PPR) also known as ‘Goat Plague’ is a viral disease that affects goats and sheep which causes huge financial loss to the animal rearers / farmers and economic loss to the country.

Causes

• The disease is caused by Moribillivirus of Paramyxoviridae family.
• Natural transmission occurs primarily through direct contact with infected sheep and goat.
• Transmission may take place through contaminated food, water, beddings and other appliances.
• Secretions and excretions are rich source of virus and spread of the disease take place through their contamination. Faeces are the main spreading agent and through it the disease may occur in epidemic proportion.
• The disease may spread in a flock through introduction of newly purchased sick animal from market.
• There is no carrier state in animals; the spread of the disease is possible through animals with subclinical infection.
• Ingestion of infected material is the main way of transmission but it may also take place through inhalation and contact with ocular secretions.
• The disease is not transmitted through insect vectors.
• Wild ruminants have been suspected to play a role in the spreading of this disease.

Clinical symptoms

• High rise of temperature (104 to 105^oF).
• The animal will show dull coat, dry muzzle and inappetance.
• There will be profuse serous nasal discharge accompanied by sneezing and coughing.
• The discharge may be crust like, hard and matt the nasal and ocular surroundings.
• Oral necrotic lesions noticed in lips, buccal mucosae, gums, dental palate & tongue, with malodour (halitosis).
• Congestion of conjunctival mucous membranes and matting of eye lids.
• Signs of pneumonia and animal may die due to respiratory distress.
• Diarrhoeic faeces may contain mucus and blood.
• Pregnant goat may abort.
• Most of the animals recover and death may occur in few of them.

Suggested first aid

• Separation of sick animals should be made.
• Adequate rest to the affected animal.
• Affected animals should be fed with porridge made of rice, ragi and kambu.
• Apply glycerin or animal fat on the ulcers.
• Immediate consultation should be made to the nearest qualified veterinary
• doctor for antibiotic treatment.
• Animals should not be allowed for grazing.
• Ulcers in the mouth can be treated with saline water or dissolve 1g of
• Potassium permanganate in 1 liter of water and wash the mouth 2 to 3 times a
• day with this solution.
• Contact your nearest Veterinary Assistant Surgeons for further advice regarding the antibiotic administration or symptomatic treatment to be given to the affected animals.
• Contact nearest Veterinary Assistant Surgeons for ring vaccination in the event of outbreak of disease.

General control and prevention management

• Regular and proper vaccination of animals.
• Vaccination Schedule

• Strict sanitation and hygienic measures are to be adopted in a flock. It is susceptible to most disinfectants, e.g. phenol, sodium hydroxide (2%).
• Restriction should be made for introduction of new animals in a flock especially in areas where the disease is prevalent.
• Sick animals bought from market should not be introduced without observation for a definite period.
• Sick animals should be segregated and treated with serum along with conservative management.
• Quarantine measures should be strictly attended in imported sheep and goat before introduction.

Sheep pox

• It is an acute to chronic viral disease of sheep and goats characterized by generalized pox lesions throughout the skin and mucous membranes.
• All breeds of sheep and goats irrespective of age and sex are affected.
• It is possible to infect goats with sheep pox virus and sheep with goat pox virus.
• Sheep are naturally susceptible to sheep pox. Younger sheep are more susceptible over old ones.
• Disease occurrence period is April- June.

Causes

• It is caused by a member of the genus Capri pox virus, pox viridae family.
• Cutaneous lesions (crust, nodules) resulting in aerosols, saliva, faeces, nasal secretions from sick animals for 1-2 months and dried scabs at ambient temperature may be the source for spread of virus.
• The usual mode of transmission is from direct contact with the infected animal.
• Indirect transmission by contaminated litter, fodder, water and attendants may spread the virus through mechanical ways.
• The virus may gain entrance through wound and abrasions.
• The virus may present in skin papules. While the affected animals rub their body on other animals, the virus is passed directly to susceptible animals.
• The biting insects (mechanical vectors) may inoculate the virus intradermally or subcutaneously.
• Aerosol or droplet infection is quite possible.
• Dog, cat etc. may mechanically transport the virus to other places.
• The virus may pass from infected mother to the foetus through placenta.

Clinical symptoms

• Skin papules appear in 2-5 days following temperature and first appear on the hairless parts of the skin.
• Soon after development of papules rhinitis, conjunctivitis may be observed.
• Papules like pock lesions appear in all the parts of the body, e.g., lips, cheeks, snout, nostril, face, ear, feet, thigh, abdomen, eye lid, neck, teat and udder.
• The eyelids are swollen and they may completely cover the eye ball.
• Mucopurulent discharges from eyes and nose.
• Animals become weak, disoriented and eventually unable to stand.
• The mucous membrane of the eyes, nose, lips, vulva and prepuce become necrotic.
• Animals die due to the development of labored breathing as a result of broncho-pneumonia.
• Animals that survive develop scab and shed over a period of 3-6 weeks, leaving a raw granulating area.

Suggested first aid

• Isolation of infected herds and sick animals for at least 45 days after recovery.
• Use of disinfectants like ether (20%), chloroform and formalin (1%), phenol (2%) to prevent the transmission of disease.
• Strict sanitary measures are to be adopted.
• Contact nearest Veterinary Assistant Surgeon for further treatment.

General control and preventive measures

• Regular vaccination of animals.
• Vaccine availability: IVPM, Ranipet, Vellore District, Tamilnadu - Sheep pox vaccine – Sheep thyroid attenuated live tissue culture vaccine - Available in 50 ml and 100 ml vials @ 60 paise per dose should be administered sub-cutaneously with the following vaccination schedule,
• Recommended vaccination schedule:

• Isolation of infected herds and sick animals for at least 45 days after recovery.
• Quarantine before introduction into herds.
• Use of disinfectants like ether (20%), chloroform and formalin (1%), phenol (2%) to prevent the transmission of disease.
• Animal traffic from the infected areas is to be prevented.
• Proper disposal of cadavers and products.
• Strict sanitary measures are to be adopted.

Tetanus

• It is a non-contagious, infectious disease of mammals caused by bacterial toxin characterized by spasmodic contraction of skeletal muscles.
• Sheep and goat are more susceptible than cattle.

Causes

• The disease is caused by bacteria known as Clostridium tetani which is remain in the intestine of the herbivorous animals as normal habitat.
• The organism can be grown under strict anaerobic condition.
• The spores are very much resistant and can persist in the soil even for years. The spores can be destroyed by boiling at 115˙C for 30 to 60 minutes.
• Vegetative forms can be destroyed by heat and disinfectants but spores are highly resistant to many physical, chemical agents and common disinfectants.
• Cl. Tetani spores require anaerobic conditions at the wound site for germination and liberate potent toxins.
• Spores may continue to persist as dormant manner in tissues for many months until favourable conditions develop for their germination.
• The organisms are very much resistant and therefore remain in the environment especially in the street dust, garden soil and animal manured soil in large number for a considerable period.
• Organisms may continue to live in the faeces for a long period of time and thus remain as a potential source of infection to man and animals.
• The organisms gain entrance through deep punctured wound contaminated with bacterial spores. Trauma and damage of the tissues caused by injection, dog bites, vaccination or chemical agents such as calcium salt, lactic acid or by infection with other bacteria may help in the initiation of the disease process.
• Organisms may gain access during parturition and manual handling of the genitalia with contaminants, retention of placenta and prolapse, castration by open method, shearing, docking and vaccination may augment the transmission if, not attended properly.
• Neo-natal animals may get the infection through contaminated umbilicus.
• Deep wound in the feet during grazing, ploughing or transport, wound of oral mucosa, dental caries, wound due to surgical interference, wounds by a penetrating object e.g. nail etc. and contaminated by dirt may influence the disease transmission.

Clinical symptoms

• Stiff gait and apathy to feed is the initial sign of the disease.
• The initial signs consist of restricted movement, muscular stiffness and difficulty in walk, lack of coordination, unusual walking.
• Stiffness of muscles of the limbs with extended back and neck arched, reporting sudden death.
• Stiff gait spasm of mouth muscles results mouth become held tight, difficult to separate the jaws, ”lock-jaw” condition.
• Prolapse of the third eye lid, head drawn on one side or back ward, pump handle position of the tail, erection of the ears, immobility of the ears and characteristic “saw horse stance” are the features.
• The rigidity of the facial muscles gives an anxious expression.
• There is restriction of mastication and dribbling of saliva from the mouth.
• Suppression of rumination and bloat are the important attributes.
• Animal remains hypersensitive and over reaction to sudden noise or physical contact and reflex irritability is noted from the start of symptom.
• Death usually occurs in 3-4 days.

General control and preventive measures

• Proper vaccination at day old should be used. Giving two doses of vaccine at least four weeks apart. An annual booster dose is recommended.
• Tetanus toxoid vaccines at the times of exposure of body tissues to environment prevent the disease occurrence.
• Providing passive immunity to the lambs by giving ewes a booster vaccination, a few weeks before lambing commences.
• Care of any local wound and make sure the wound is not contaminated by dirt.
• Cleanliness and proper hygienic measures are to be adopted at the time of parturition and following parturition.
• The animal should not be allowed to graze near barbed wire fencing.
• Yards should be watered to decrease dust.
• Open method of castration should be discouraged in the village level.
• Proper care should be taken to handle the retention of placenta and prolapsed cases.
• Sterile surgical instruments are to be used at the time of operation.
• Wound should be drained with deep incision. The animal should be kept away from metallic and sharp objects.
• Hygiene is essential while undertaking any husbandry or surgical procedure.
• All out precautions should be taken during castration.

Prevention of infection and infestation

• Feed should be placed in troughs that cannot be contaminated by faeces.
• Waterers and feed troughs should be kept clean and free of contaminants.
• Good grazing management to control pasture or grassland borne helminthic infections.
• Use of clean or safe pastures (not grazed for 6 to 12 months) will help to control helminths problems.
• Rotational grazing of livestock species should be followed to minimize or limit the infection from pasture.
• All new arrivals to the farm should be isolated for at least 30 days and dewormed.
• Young animals should be housed separately from adult animals to prevent disease spread.
• Infected/Infested animals should be removed from the flock or herd and housed separately.
• Treatment should be followed by chemoprophylaxis to prevent reinfection.
• Vaccines may be used to prevent infection, if suitable vaccines are available.

Vaccination schedule for sheep and goat

How to control and reduce the infection as soon as outbreak occurs

• Segregate sick animals.
• Stop all animals, animal products, vehicles and persons coming into and out of the farm.
• Call a veterinarian for advice, adopt containment vaccination.
• Avoid grazing in a common place.
• Ban all visitors to the farm.
• Provide foot dips containing disinfectants at the entry of the farm and gear up sanitation and hygiene.

Source: Expert System for Sheep & Goat, ICAR-TANUVAS-TNAU

Related Resources

1. Technologies developed by TANUVAS,Tamil Nadu (1.6MB)