Common Diseases of Farm Animals

by Robert Alexander Craig

The symptoms vary in different cases, depending on the organs affected, and the virulence and amount of virus introduced. The apoplectic form is very acute. The disease sets in suddenly; the animal trembles, staggers, falls and dies in a convulsion. Blood may be discharged from the nose and with the urine and faeces.

In the abdominal form, abdominal pain, diarrhoea, prolapse of the rectum, bloating and doughy swellings in the region of the abdomen occur.

In the thoracic form, the symptoms are bloody discharge from the nostrils, salivation, rapid, difficult breathing and swelling in the region of the throat. Local or skin lesions may occur in conjunction with, or independent of, the above forms of disease. These are carbuncles one or two inches in diameter that are hot and tender at first, but later become gangrenous, diffused swellings.

On post-mortem examination the blood is found tarry and dark, and bloody exudates may be found in the abdominal and thoracic cavities. The spleen is soft and two or three times larger than normal. The diagnosis should be confirmed by finding the B. anthracis in the blood and tissues. The death-rate is very high, usually about seventy-five per cent.

The treatment is preventive. Animals should be kept away from lots and pastures where deaths from anthrax have been known to occur, unless immunized against the disease. Marshy, swampy land that is infected with the germs of anthrax should be drained and cultivated.

When an outbreak of the disease occurs, all of the animals should be vaccinated. The carcasses of the animals that die should be cremated at or near the place where they die. If hauled or dragged, the necessary precautions should be taken against scattering the infectious material from the carcass, and plenty of disinfectants used. Persons attending the animals should be warned against opening or handling the carcass without protecting the hands with rubber gloves.

Anthrax vaccine should not be used by incompetent persons.

ULCERATIVE STOMATITIS. (ULCERATIVE SORE MOUTH.)—This is an infectious disease of young animals. Pigs from a few days to a few weeks of age are the most commonly affected.

The specific cause of ulcerative sore mouths is the Bacillus necrophorus (Fig. 104). The infectious agent is distributed by the udder of the mother becoming soiled with filth from the stable floor and yards, and by affected pigs nursing mothers of healthy litters. Filth, sharp teeth and irritation to the gums from the eruption of the teeth are important predisposing factors.

The symptoms are, at first, an inflammation of the mucous membrane lining the lips and cheeks and covering the gums. The inflamed parts are first swollen and a deep red color; later, white patches form and the part sloughs, leaving a deep ulcer. As ulceration progresses, difficulty in nursing increases until finally the young animal is unable to suckle. If ulceration of the mouth is extensive, the animal may be feverish, dull and lose flesh rapidly. Portions of the lips, gums and snout may slough off. The death-rate in pigs is very high.