ENZOOTIC ABORTION IN COWS. 119 



at must be of an infectious or contagious nature. It must ])e 

 remembered, that while all contagious diseases are of an in- 

 fectious, still, all so-called infectious maladies are not neces- 

 sarily of a contagious nature. 



It has previously been remarked, that the New York com- 

 mission did not seem to have had the idea that the cause of 

 this disturbance was of an infectious material ; hence it is but 

 just to them to let them speak for themselves. 



They appear to have come to the conclusion that abortion 

 was chiefly due to unnatural conditions produced in cows, 

 from the inconsiderate forcing process to which man's greed 

 subjects the sexual and milk-producing organs, not only with 

 reference to degree, but also with regard to the unnaturally 

 «arlv ase at which we cause their functions to be called into 

 full activity. 



After describing the manner of ' ' selection " by which man 

 has gradually produced our present milk-machines, they tell 

 us: — " That if, however, instead of following these rules, 

 the attempt be made to get a large increase at once ; first, 

 by forcing the uterine reproductive apparatus into activity 

 before the animal has arrived at full maturity, and afterwards 

 by continuing the drain upon the mammary secretion, at the 

 same time that a second foetus is getting its supply from the 

 placenta. By tlie first practice the uterine reproductive ap~ 

 jparatus is weakened, and a liabilii// to abortion established. 

 By the second, the natural supply of blood lohich should go 

 •during pregnancy to the uterus to nourish the young, is con- 

 tinued to be drawn in the other direction towards the udder; 

 arrest of development from inanition is endangered, and 

 when it occurs C^ B) the foetus is expelled as a foreign body.'' 

 It is scarcely necessary to say that such deductions are en- 

 tirely of an a priori nature with reference to enzootic abor- 

 tion, though a sporadic case may occasionally occur, or even 

 several cases, in a very large herd which is subjected strongly 

 to the forcing system. 



Even this report frequently quotes cases of abortion oc- 

 curring: in herds on the introduction of a cow from a farm on 

 which it had prevailed ; but this does not seem to have made 

 any impression upon the minds of the commissioners. The 

 latter sum up their conclusions as follows : — 



