Aids to stockowners / by J. Walker.

  • John Walker
Date:
1930
Catalogue details

Licence: In copyright

Credit: Aids to stockowners / by J. Walker. Source: Wellcome Collection.

    51/198 page 33
    ANTHRAX. This disease is due to the bacillus anthracis, which gains entrance to the blood-stream and causes a fatal septicaemia. It is widely prevalent in this Colony, and is undoubtedly spreading as the result of the indiscriminate opening of car¬ casses of bovines and other animals which have died suddenly, and by the unrestricted movements of hides by natives. Car¬ nivorous birds, by feeding on anthrax flesh, also disseminate the disease, as spores of the anthrax bacilli are capable of passing undigested through the stomach and intestines and reaching the ground in the faeces, where they rapidly pro¬ lifers tp. Once infection appears on a farm it is doubtful whether it will ever be eradicated by present means, as it has been shown m America that growing plants and grasses are capable of bringing anthrax spores to the surface from underlying deeply buried carcasses. It is thus obvious that on farms where anthrax has once occurred annual vaccination should be carried out as a routine, and no carcass opened until anthrax has been eliminated as the cause of death. Cause. The cause is a specific bacillus which is pathogenic for all the domestic animals and man. Wild ruminants are also susceptible, and elephants die from the disease. Birds are highly resistant, but fatal cases have been reported from South Africa in the ostrich. Cold-blooded animals are immune. In the blood-stream the organism exists as bacilli, but as soon as blood is spilt and exposed to the air spores are formed which are exceedingly resistant to ordinary disinfectants. It is by these spores that infection is maintained on a farm, and it is known that spores may remain viable, in the ground for many years. Sources of Infection. I ndoubtedly the commonest route of infection is by the ingestion of food and water containing the spores or mature organisms. Certain proprietary cattle cakes contain the spores but in the majority of cases in this country cattle are infected by eating or drinking food and water contaminated by the specific organism. It is known that biting flies (stomoxyes) are capable of transmitting this disease to cattle and horses in South Africa, but it is not known if this means of trans¬ mission exists in this Colony. In man, anthrax generally
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