DISEASES OF SHEEP. 53 



amongst a vaccinated herd. 4. Natural pox may happen 

 at all seasons of the year and under all possible circum- 

 stances, whereby another considerable loss may be incurred 

 by the infection of ewes, which destroys the ewes as well as 

 other lambs ; but vaccination can in most, cases be post- 

 poned until a proper time, and the loss thereby in some 

 measure avoided. 



The above-mentioned facts alone are sufficient to show 

 the manifest advantage of vaccination, a still greater 

 benefit being, however, observed when such vaccination is 

 undertaken in due time, inasmuch as even the best remedy 

 may lose somewhat of its effects if applied too late. Con- 

 sequently, if a herd is already afflicted with pox, only the 

 disinfected or healthy animals can be vaccinated with a 

 beneficial result ; and even in such cases a great many 

 sheep may be saved and the duration of the disease con- 

 siderably shortened. A vaccination undertaken under such 

 circumstances is called "vaccination in distress." Such a 

 vaccination, although of comparatively less benefit, ought 

 to be undertaken under all circumstances, except upon 

 ewes going with lambs ; in such cases, the ewes should be 

 examined daily and the healthy separated from the in- 

 fected, until the danger of infection appears to be removed, 

 which will be more fully explained hereafter. When the 

 disease is known to exist in the neighborhood, the owner 

 cannot do anything better than to vaccinate his flock, and 

 by this means to prefer a probable and small loss to a large 

 loss of an uncertain extent. In such a case we call such 

 an operation " precautionary vaccination," and it is always 

 advisable in the case named. Experience proves that all 

 other precautionary measures are inadequate to prevent 

 the transfer of sheep pox from one locality to another ; and 

 if such a precautionary vaccination is neglected, vaccina- 

 tion in distress may be afterward required, and a partial 



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