ABORTION 109 



Early conception, often at an age of fourteen to fifteen 

 months, in consequence of which the heifer bears a calf when 

 two years old, accustoms the generative organs to an early 

 function. The cow calves every year, and is expected to give 

 plenty of milk even in a well-advanced stage of pregnancy. 

 Even by feeding her heavily before the first parturition one 

 attempts to increase future lactation. 



Stockfleth is right when he says that in the cow keen 

 competition exists between the uterus and the mammary glands, 

 each doing their utmost to appropriate a part of the nutriment 

 destined to develop the foetus and milk production. The 

 weaker one succumbs, and if it be the uterus, abortion takes 

 place. 



The conditions enumerated above usually do not suffice to 

 produce abortion. They can only be termed predisposing 

 causes. Often insignificant causes, in themselves unable to 

 produce abortion, do so when the above named conditions 

 exist. The effects of all causes, infectious and non-infectious, 

 to be mentioned separately, are much more powerful when the 

 animal is predisposed. Direct causes are : 



1. Disturbances of tlm circulation, influencing the circulatory 

 territory of the gravid uterus. Circulatory disturbances may 

 create labor pains. During ordinary parturition, the reflex 

 hypersemia from the ovaries produces uterine contractions 

 (Franck). 



Ill that time when abortion takes place the uterus is much 

 less sensitive than toward the end of the period of gestation. 

 Venesection changes blood pressure when a good deal of blood 

 is abstracted, and may produce abortion. For this reason, 

 phlebotomy is not to be practiced on the pregnant animal. 

 Psychic influences may effect a reflectory narrowing of the 

 blood vessels, and thus somewhere else a collateral hypeisemia. 

 Several instances are known where a cow suddenly frightened 

 aborted. 



Retarded venous circulation, as by pressure upon the 

 posterior vena cava, the blood flowing through the uterus con- 

 tains much carbon dioxide. The foetus itself is unfavorably 



