Home / Diseases / Sheep Diseases and Control

Sheep Diseases and Control

Sheep Diseases and Control  Management:-

Sheep-Pox
Epidemiology :
Sheep-pox is a highly contagious disease.It causes a mortality of 20 to 50 per cent in animals below the age of 6 months, and causes damage to the wool and skin in adults.Of the pock diseases, sheep-pox ranks only second to human small-pox in virulence.The disease is transmissible to in contact goats but not to other species of animals. It, however, spreads slowly.
Symptoms:
The disease in characterized by high fever, and symptoms of pneumonia and acute enteritis.Skin lesions appear particularly in parts free from wool, notably around the eyes, inner side of the  thigh, udder and under surface of the tail. The internal organs such as trachea, lungs, kidneys and intestines are also affected.The disease results in emaciation and, as already mentioned, frequent  deaths of affected animals.
Treatment, Prevention and Control:
 The diseased animal should be treated with palliatives.In the young ones nursing is more important than medication.The infected litter should be burnt and the bedding changed every day.Affected animals should be kept on soft diet.The ulcers on the skin should be washed with potassium permanganate lotion and dusted with boric acid; strict hygienic measures should be adopted.The method of control by the use of vesicular fluid was in vogue for dealing with sheep-pox.A couple of sheep were first inoculated with the  vesicular fluid on the under surface of the tail or the inner side of the ear by scarification.In about 4 to 6 days vesicles appear at the spot, and the fluid collected from these vesicles, mixed with equal parts of glycerol, served as a vaccine.Vaccination was done by scarification inside the ear or under the tail.In about 15 to 20 days, the animals becomes resistant to the disease.
(Source: Dr.Acharya, Handbook of Animal Husbandry)
BRUCELLOSIS OF SHEEP :-

Transmission:
A large number of organisms are eliminated ruing abortion.The mode of entry is by ingestion or via conjunctiva.The aborted foetus,vaginal discharge and milk from infected goats contain a large number or organisms.
Symptoms:
In infected goats and sheep state of abortion may occur followed by a quiescent period during which a few abortions occur.The aborted animals do not breed.After 2 years or more another abortion storm is likely to occur.
Diagnosis, Treatment and Control:
It is not possible to diagnose brucellosis on the basis of symptoms alone.The suspicion is aroused when humans in contact suffer from undulant fever and there is poor breeding record in goat herd and evidence of mastitis.The diagnosis can be done by the isolation of organisms and by serological tests.
There is no adequate treatment:
This is based on hygiene, vaccination,testing and disposal.Good management practice is essential. Separate quarters should be provided for kidding.Immunization can be done with attenuated as well as killed vaccines.The test and disposal procedure is highly desirable.
TETANUS:-
This is an infectious, non-febrile disease of animals and man, and is characterized by spasmodic tetany and hyperaesthesia. This disease is prevalent all over the world.
Transmission:
Infection takes place by contamination of wounds.Deep punctured wounds provide favourable conditions for the spores to germinate, multiply and produce toxin which is subsequently absorbed in the animal body.The micro-organism is present in soil and in animal faeces, and is carried into the wound by a penetrating object.The organism is present in the intestine of normal animals, and under some undetermined conditions multiplies rapidly and produces toxin in sufficient quantities to be absorbed and cause the disease.
Symptoms:
The incubation period is generally 1-2 weeks but it may be as short as 3 days. Tetanus affects many species of domesticated animals but occurs particularly in horses and lambs; less frequently in adult sheep, goats, cattle, pigs, dog and cats; and rarely in poultry.The initial symptoms are mild stiffness and an unwillingness to move all the animals. More severe symptoms develop after 12-24 hours which are stiffness of limbs, neck, head, tail and twitching of muscles.The spasms develop in response to noise.In terminal stages ears are erect, nostrils dilated,nictitating membrane protruded. Mastication becomes very difficult because mouth can not be opened, hence the name lockjaw.
Treatment:
In cattle changes the recovery with treatment are better than horses or sheep. The treatment is carried out by first injecting antitoxin then treating the wound.Penicillin parenterally is beneficial. Muscular relaxation is achieved by injection of relaxants.The animal should be kept in a dark room and fed with the help of stomach tube.
Control:
Proper hygiene and cleanliness at castration and other surgical procedures should be observed. Sheep should be given 2 injections based 3 weeks apart to develop a solid immunity.
LISTERIOSIS:-

Transmission:
The organisms are excreted in the faeces, urine, aborted foetuses, uterine discharge and milk of infected animals.The organisms are sufficiently resistant to remain viable in animal and human faeces,sewage,soil,silage and dust foe several weeks and months.The blood sucking arthropods may spread infection since organisms have been  isolated from cattle ticks and tabanid flies.Under natural conditions certain predisposing factors are related to clinical infection.
Symptoms:
In farm animals the disease occurs towards the end of winter or early spring. The first signs of meningo- encephalitis are stiffness of neck, inco-ordinated movement of limbs and tendency to move in circles or to lean against a fence or wall. There may be paralysis of muscles of jaw and pharynx. Inco-ordination becomes progressively more severe until the animal can no longer stand. The cattle which are not severely affected may survive. Abortions in cattle usually  occur after 4-8 months of pregnancy and at a comparatively later stage in sheep. In pigs and horses, clinical signs are not common but may develop as encephalitis and septicaemia. In poultry, the disease usually causes sudden death, occasionally there are signs of torticollis, weakness and inco-ordination of the legs.
Treatment:
Tetracyclines are very effective in meningo-encephalities of cattle less so in sheep. The recovery rate depends on the speed with which the treatment is commenced.
Control:
When outbreaks occur all affected animals should be slaughtered and buried along with litter and bedding. The vaccines, living or killed, have little effect on the pathogenesis of infection under natural conditions, Tetracycline’s are very effective for treatment of listeriosis.
CAMPYLOBACTOR ABORTION ( vibriosis ):-

Transmission:

Transmission occurs by coitus.The affected bulls carry the organisms in proputial cavity indefinitely.Mature cows and heifers also carry the infection for long periods. Infected semen from an infected bull is the important means of the disease. The organism survives low temperature used in semen storage.
Symptoms:
Infertility may cause become apparent only when the percentage of pregnancies in a dairy herd is low.The infertility rate in heifers is more than in cows. Abortions usually occur between fifth and sixth month of pregnancy. Infected bulls show no symptoms and their  semen is normal. Healthy bulls become infected during coitus with diseased cow. Among sheep the disease is characterized by abortion occurring towards the end of gestation. Usually abortion is preceded by vaginal discharge for several days.The aborted foetus is edematous with petechial hemorrhages on serous surfaces and necrotic foci in the liver.
Control:
Abortion rate can be reduced by antibiotic therapy, and particularly by using chlortetracycline and concurrently with the development of specific immunity. The use of killed vaccines may reduce the incidence of disease in a herd but does not eradicate the infection. The bulls can be treated by injecting antibiotic cream in the prepuce. There is no direct treatment of females.
JOHNE`S DISEASE:-

Johne`s disease is a specific chronic contagious enteritis of cattle, sheep, goat, buffaloes and occasionally of pigs. The disease is characterized by progressive emaciation and in cattle and buffaloes by chronic diarrhea and thickening of the intestine.
Transmission:
Under natural conditions the disease spread by ingestion of feed and water contaminated by the faeces of infected animals.The infection occurs mostly in the early month of life. The incubation period extends from 12 months to several years. The animal aged 3 to 6 years mostly suffer from the disease. Affected animals may not show clinical symptoms continue to discharge organisms in faeces. The organisms persist in pastures for about 1 year.The organisms are susceptible to sunlight, drying and high PH of soil; continuous contact of urine with faeces reduces the life of bacteria. In cattle clinical signs appear mainly during 2-6 years of age. The infected animals which are apparently healthy, often show clinical signs after parturition.
Treatment:
The organisms is more resistant to chemotherapeutic agents invitro than Mycotuberculosis. Because of this the practical utility of treatment in clinical cases is poor.
Control:
The affected animal should be segregated and their faeces Properly disposed off. Alive vaccine have been developed. It reduces the incidence of clinical disease. It consists of a non-pathogenic strain of Jhone`s  bacillus with an adjuvant. The calves soon after birth are inoculated with vaccine subcontaneously. The vaccinated animals become reactors of Jhonin. Vaccination is generally done in heavily infected herds.
shepdisease

Leave a Reply

Your email address will not be published. Required fields are marked *