THE COW IN HEALTH AND DISEASE 99 



dairies is not only from the number of calves 

 that are lost, but the loss in milk flow and the 

 trouble that is consequently encountered in get- 

 ting the cow to conceive again. 



This disease is caused by the bacillus Coryne- 

 bacterium Abortus Infectiosi. It may retain its 

 virulence for several months in the uterus of the 

 cow, in its secretions or in the dead foetus. 

 It is destroyed very readily by very mild anti- 

 septic solutions. 



The infection may be taken up by the external 

 genital organs but more often it is transmitted 

 to the cow from the bull during copulation. The 

 bull usually receiving the infection from serving 

 some cow which is already infected. The infec- 

 tion may be introduced by various objects that 

 are used in caring for the animals. It may also 

 be taken up with the feed and water — the feed 

 and water becoming contaminated by the mem- 

 branes and fluids which envelop the foetus. The 

 infection of the male by the female and the con- 

 sequent infection of other females soon spreads 

 the infection through a large herd. The abor- 

 tions are usually some little time apart, and, 

 after the first one or so occurs, there will be 

 some time elapse and it may be some little time 

 before the owner awakens to the fact of the ac- 

 tually existing condition. In this way it is al- 

 lowed to gain a foothold and the means that 

 should have been applied for its prevention have 

 not been used. 



This infection which gains access to the va- 



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