258 VETERINARY HYGIENE 



The virus in the spore form is very resistant. Putrefaction and 

 desiccation have very little effect upon it. Five per cent, carbolic 

 acid is only fatal to artificial cultures containing spores in 10 hours. 

 Spores contained in natural products of the disease are much more 

 resistant than when in artificial culture, especially when such 

 natural products, e.g., muscle, are dried before being heated. Thus 

 the fresh muscle enclosed in a tube is rendered sterile in 2 hours at 

 80 C and in 2 minutes at 100 C, but if such muscle be quickly dried 

 at 35 C and then mixed with water, 2 hours at 100 C are required 

 to completely sterilize it (Arloing, Cornevin and Thomas).* Dried 

 and powdered muscle may be heated to 100 C for six hours without 

 being rendered completely sterile. 



PREVENTIVE MEASURES. Drainage and cultivation of the land 

 take first place in the prevention of black quarter. Liming of 

 pastures is also recommended. Should the disease appear 

 frequently the infected pastures should be ploughed up and used for 

 corn growing. If impossible to do this susceptible animals should 

 be kept off such pastures, which should only be used for maintaining 

 adult stock. 



Affected animals if seen alive should be isolated, but the animal 

 is often found dead without symptoms having been noticed. The 

 carcase of an animal which died of black quarter should, if possible, 

 be cremated owing to the fact that putrefaction has no destructive 

 effect upon the virus. As a rule, however, this method is imprac- 

 ticable, and in any case costly, and in consequence one is thrown 

 back upon burial. Burial should, if possible, be in a place to which 

 cattle and sheep have no access, it should be deep and there must 

 be no mutilation until, at any rate, the carcase is in the grave. 

 Dung and soiled litter where the animal has been housed should be 

 disposed of with the carcase. Carcases of animals dead of black 

 quarter are quite unfit for human food. 



One attack confers a considerable degree of immunity. The 

 ancient practice of setoning has now fortunately to a great extent 

 fallen into disuse, as no measure of protection is thereby afforded. 

 A high degree of immunity can, however, be established by means 

 of vaccination. To Arloing, Cornevin and Thomas and to Kitt 

 special credit is due for having introduced the methods called 

 after their names. These are shortly as follows : 



(1) Method of Arloing, Cornevin and Thomas: Pulp from a 



perfectly fresh black quarter lesion is spread in a thin layer on a 



plate and dried at 32-35 C ; one part of the dry residue is triturated 



in a mortar with two parts of water to form a paste, which is placed 



*Journ. Comp, Path., 1898, Vol. XL, p. 148, Quotation. 



