652 PATHOLOGY OF PARTURITION. 



by evacuants, with external and internal stimulants, is offered as addi- 

 tional proof ; though it is not contended that the toxic agent is the 

 same in both maladies — the agent in haemoglobinuria acting alike on 

 the nervous and vascular systems, while in puerperal collapse its direct 

 action is exerted on the nervous system only — any vascular phenomena 

 observed post mortem being merely the result of vaso-motor paralysis 

 {Walley). 



But it may be observed that even this hypothesis does not meet all 

 the requirements of the pathologist ; for if the malady were due to a 

 toxine, surely the flesh of affected animals would prove toxic when used 

 as food. Such is not the case, however, as all experience, experimental 

 and other, goes to show ; and there are other facts as important which 

 cannot be explained by this hypothesis. 



In trying to account for the evolution of the malady, it is necessary 

 to remember that it exclusively affects Bovines of the female sex ; that 

 it is observed chiefly, if not entirely, in well-bred and well-fed animals 

 which yield a large quantity of milk, are of a certain age, and usually 

 after they have had their third calf ; that it most frequently becomes 

 manifest in two or three days after parturition, rarely before that event, 

 and always after an easy and quick delivery ; that its advent is sudden 

 and course serious and rapid, the terminations being death or speedy 

 recovery, generally without any period of convalescence. 



It may well be questioned whether an animal toxine in the blood 

 would produce the phenomena denoting this disease under such circum- 

 stances, apart from the fact of the innocuousness of the flesh of affected 

 animals when consumed as food. 



It must be remembered that the predisposed Cow during pregnancy 

 and before parturition occurs, is in a state of exalted physiological 

 plethora and high vascular tension, much beyond that of the females 

 of any other species at the same period, owing to her organization 

 and the great artificial development of the lacteal apparatus. In 

 other female animals when birth takes place, the extra blood de- 

 manded for the development of the foetus in utero, is now diverted 

 to the mammary glands to supply it with the nourishment it needs 

 for a certain time after it is born ; in this way the vascular system 

 is enabled to maintain its equilibrium immediately after parturition, 

 and gradually to resume its normal condition as the young creature 

 is competent to subsist independent of its parent. In the non-predis- 

 posed Cow under natural conditions this also occurs, and nothing 

 different is observed from what is seen in the Mare, Sow, Bitch, 

 or other creature at the post-parturient period. But when, from any 

 cause, the excess of blood which was required for the growth of 

 the foetus is not diverted to its natural purpose after the young animal 

 is born, there is a rapid transition from physiological action to patho- 

 logical processes in all animals, as well as in woman, in whom, owing 

 to constitutional fault, or causes interrupting the due course of involu- 

 tion, the work of metabolism or conversion of the now superfluous 

 tissues formed during pregnancy, and of absorption and elimination, is 

 imperfectly performed. ^ 



Predisposed as is the Cow by artificial management, and possibly by 



anatomical and physiological peculiarities, the pathological changes 



which ensue more or less promptly after parturition when the vascular 



tension is not reduced, and the substitution of absorption and milk 



^ Dr. Barnes, The Lancet, December 1, 1894. 



