COW-POX 71 



a relatively permanent immunity. Immunisation 

 against the disease by vaccination with serum from 

 the pleural cavity of infected animals has been 

 practised. The material is injected subcutaneously. 

 Its use is attended with danger, as up to 5 per cent, 

 or even more of those vaccinated have been killed by 

 the vaccine. Nocard and Eoux have advised vac- 

 cination with pure cultures, and claim to have 

 secured more favourable results than by the older 

 methods. Nocard has also produced a curative and 

 prophylactic serum by the hyperimmunisation of 

 animals by the injection of increasing doses of pure 

 culture until 6 litres have been used. In doses of 

 40 c.c. it serves as an efficient prophylactic, and in 

 larger amounts as a curative agent in the early stages 

 of the disease. 



Cow-Pox( Variola Vaccina). — Cow-pox, the relation 

 of which with human pox has already been recognised 

 by Jenner (1796), occurs usually only sporadically, 

 or as an enzootic confined to individual herds. In 

 most cases it may be attributed to an infection of 

 true pox or vaccination pox of man. It is a mild 

 disease, attacking chiefly the teats of cows, and 

 causes considerable economic waste in dairy herds, 

 owing to the loss of milk caused by the difficulty of 

 milking the infected animals. Under medicinal 

 treatment it may be often difficult to eradicate, as 

 new animals, when introduced into the herd, become 

 affected. 



