GENERAL CARE OF CATTLE. 353 



overtaxed, there is no reason why healthy cows, 

 treated in a sensible way, should not stand at 

 the first service. For various reasons, which 

 are in the main not capable of explanation, 

 many cows miss the first and sometimes several 

 services. If no evidences of ill-health are dis- 

 cernible and the bulling is regular, there is 

 nothing to be done but to return the cow at 

 each heat to the bull, or to some other bull. 

 The latter plan sometimes proves at once suc- 

 cessful, showing that the difficulty lay with the 

 bull. 



All diseases affecting the generative organs 

 are somewhat insufficiently understood. This 

 is especially true of abortion. Abortions fall 

 into two broad classes: those caused by some 

 local trouble of sporadic origin, and those 

 caused by some epidemic or endemic disease. 



The sporadic cases of abortion are generally 

 due to some constitutional disease which reacts 

 upon the foetal system or to some local affec- 

 tion of the womb. Animals affected with any 

 form of tuberculosis are especially subject to 

 abortions. The highly heritable nature of tu- 

 berculosis makes it almost a blessing that this 

 is so, for any means that will check the spread 

 of so dangerous and so insidious a disease de- 

 serves welcome. There are many other dis- 

 eases which lead to a general weakness of the 

 system which will induce abortion. Not only 



