SMALL-POX IN SHEEP. 239 



and rabbits are subject to the disorder, and may be the 

 carriers of the contagion. Sheep dogs certainly can be the 

 means of transmitting the virus. The malady has been 

 observed on them, and a marked case occurred in Wiltshire. 

 Mr Charles Percivall had an opportunity of observing the 

 disease on Mr Stephen Neate's dog, and informs me that the 

 symptoms were identical with those of variola ovina, and 

 there could be no doubt that the dog contracted the disorder 

 from the diseased sheep. The disease has been communi- 

 cated by inoculation to man and cattle. 



When small-pox enters a flock, it may be checked and 

 limited to a few cases, or it may affect the whole. I have 

 observed that the disease is far more severe in countries 

 where it is the practice to house the sheep. Few escape, and 

 the majority die. It is this that renders all the German 

 veterinarians such decided partisans of the practice of inocula- 

 tion. They find that sometimes not one per cent, die where 

 flocks are inoculated, whereas 50, 60, 80, and upwards of 90 

 per cent, are destroyed by the natural disease. 



In proportion to the close, hot, and ill-ventilated condition 

 of stables in which sheep are congregated, is the mortality 

 heavy. The malady spreads far more certainly and rapidly 

 amongst the continental flocks than our own. Here the 

 course of the disease usually consists in the attack of one or 

 two animals which probably survive, but not being separated 

 from the flock, contaminate dozens. In the course of about 

 a month several score of sheep are affected, and in two, three, 

 or four months, every member of a flock of one or two 

 thousand sheep may have been seized. Where a flock of 

 sheep is housed, the disease is propagated to every animal 

 in as many weeks as it takes months on our hills. Many 

 vigorous animals in a flock prove rather refractory to the in- 

 fluence of the virus, and some may escape altogether. This 



