Sheep - AgRIS

contents by neutralization tests with mice. Animals that die suddenly may show no lesions
whatever. Small haemorrhages may be present under the epicardium or endocardium. There
is commonly present a haemorrhagic inflammation in the mucous membrame of both the
abomasum and duodenum. Softening of kidney as a postmortem change that is not appearent
untill 3 to 4 hours after death. Putrifaction of the carcass takes place early. Hyper -immune
serum is an effifcient short term prophylaxis. Sulphadimidine is reported to be effective.
There are two major control measures available, reduction of the food intake and
vaccination. A method of reducing the grain intake of lambs self fed in feed lots is to mix
clemental sulphur. (7.5 g. per day per lamb) in feed. Entertoxaemia vaccine is a culture of a
highly toxigenic strain of clostridium type D grown in anaerobic medium rendered sterile and
atoxic by the addition of solution of formaldehyde in such a manner that retains its immunising
properties. In sheep 2.5 ml are injected sub-cutaeneously and is repeated after 14 days with
same quantity. Lambs and sheep vaccinated during the previous year require only one
injection in the subsequent year. Immunity conferred by this vaccine is for one year.
Entertoxaemia caused by clostridium perfringens. Type & B. & C.
Infection with cl. perfringens Types B. and C results in severe entritis with diarrhoea and
dysentery in lambs. These include lamb dysentery (cl. perfringens Type B), struck (cl.
perfringens Type C.) , and haemorrhagic enterotoxaemia (cl. perfringens Type C.). In affected
groups of lambs due to type B the morbidity rate may reach as high as 20 to 30 percent. The
mortality rate approaches 100 percent. Struck caused by cl perfringens type C affect adult
sheep, particularly when feed is abundant. The charactersistic effect of the beta-toxin, the
important toxin produced by cl perfringens Types B and C is the production of haemorrhgic
enteritis and ulecration of the intestinal mucosa. The lesions described for ― Struck‖ in adult
sheep and the haemorrhagic enterotoxemia in young lambs are similar. The syndrome of 2
weeks old. In the more common acute form, there is severe abdominal pain; recumbency,
failure to such and passing of brown fluid faeces some times containing blood. Death usually
occurs with in 24 hours. The diagnosis is made by testing the intestinal contents for toxins and
the isolation of the organisms. Multicomponent clostridial vaccine is inoculated 5 ml. subcutaeneously
and repeated after 14 days.
iii) Tetanus
It is an acute infectious disease manifested by toxic convulsions of the voluntary muscles.
Among the domestic animals the sheep occupies the position next to horse in suseptibility. In
sheep it more commonly follows the routine operations such as shearing,docking,castration and
even vaccination. Clostridum tetani forms spores which are capable of persisting in soil for
number of years. The spores are resistant to many standard disinsfection procedures including
steam heat at 212 °F (100 °C) for 30 to 60 minutes but can be destroyed by heating to 239 o F for
20 mintues. Cl tetani organisms are commonly present in the faeces of animals, especially
horses. The portal of entry is usually through deep puncture wounds A high incidence to
tetanus may occur in lambs following castration, shearing and docking. Docking by the use of
elastic band ligatures appears to be especially hazardous. In sheep the first symptom is usually
stiffness of the limbs, saw buck attitude, lock jaw, opistholonous is common. The tail stands
out in a rigid position. Death occurs by asphyxiation due to fixation of the muscles of
respiration. The main principles in the treatment of tatanus are to eliminate the causitivie
bacteria, neutralize residual toxin, relax the muscles to avoid asphyxia. Tetanus antitoxin is
usually administered but is of little value when signs have appeared. To control it lambs are
usually given 100 to 150 units of antitoxin subcutaneously after docking .
iv) Pasteurellosis
Pasteurellosis is usually pneumonic in form although a septicaemic form is not uncommon
in lambs. Morbidity and mortality rate reaches up to 40 percent. Death losses in feeder lambs
are usually of the order of 5 percent, but may be as high as 10 percent to 20 percent. In sheep
Pasteurella haemolytica is often the primary cause. The transmission occurs by the inhaltaion
or ingesion of the infected material. In outbreaks, sheep show high rise of temperature,
mucopurulent discharge from eyes and nose, coughing depression, froth in the mouth, anorexia,
increaseed pulse and respiration. The dignosis is made in the isolation of the organisims from
the heart blood. Little information is available on the treatment of Pasteurellosis in sheep.
Administration of sodium sulphadimiadine gives excellent results with a 1 g per 7 kg body
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