222 PATHOLOGY OF PREGNANCY. 



they only come away when decomposition sets in. The influence of 

 these putrefying membranes has been noted by several veterinarians — 

 Pele, Barrier, Cruzel, Bouley, Eychner, Haubner, and others — who 

 imagined that the putrescent emanations infected the economy of the 

 animals breathing them ; but Zundel thinks it more probable that 

 direct infection takes place by the genital mucous membrane. In 

 support of this opinion, he quotes the observations of Eoloff, who asserts 

 that he always saw the disease or accident developed in stables or sheds 

 where the distance between the mangers and drains was small, or where 

 the drains did not have suflicient fall, whereby the hind quarters of the 

 animals were readily soiled by the excreta in them. 



The micro-organism may obtain introduction to the genital passage 

 of pregnant Cows through actual contact with these matters, or the air 

 may carry it to them when the discharges have become dried. 



There is evidence, then, which leads to the belief that, beside the 

 other causes which have been cited as giving rise to abortion, there is a 

 specific germ that, when transmitted from an animal that has aborted, 

 or from the aborted foetus or its envelopes, to another pregnant animal 

 of these same species, will cause it to abort. Clinical, experimental, 

 and hygienic observation are in favour of this opinion, which if it cannot 

 be accepted as absolutely confirmed in every respect, yet affords at any 

 rate a good working hypothesis that satisfies the exigencies of everyday 

 practice. 



Whether the abortion germ is identical in every species of animal is a 

 question still to be solved — though it probably is not, as Mares have 

 aborted among pregnant Cows, Ewes have done the same, and rzcc versa, 

 without abortion going beyond the one species. 



Symptoms. — It is rare that this kind of abortion occurs before the 

 third or fourth month of gestation ; more frequently it is at the fifth, 

 sixth, or seventh month, or even later. There are no premonitory 

 symptoms, except perhaps a trifling uneasiness for a few hours pre- 

 viously, with sinking of the flanks and descent of the abdomen ; the 

 animal generally looks well and hearty, and yields its supply of milk as 

 usual; and soon after the foetus is expelled, apparently without any 

 effort or inconvenience, and along with its membranes, if these are not 

 ruptured, with or without them when they are. It is rare, however, 

 that the ruptured membranes are rejected immediately after the foetus ; 

 as a rule they are nearly always retained, particularly when pregnancy 

 is advanced ; and they putrefy in the uterus, being got rid of only in 

 shreds at intervals. ^A'hen attempts are made to remove them by hand, 

 this is found much more difficult than after ordinary parturition ; owing 

 to the membranes being very adherent, the cotyledons have to be 

 enucleated separately, and even then the membranes come away in 

 fragments. Then the animal generally loses its appetite and condition, 

 goes off its milk, and sometimes perishes, probably as a consequence of 

 this placental retention. If it recovers, oestrum appears unnaturally 

 frequent, though conception is infrequent and sterility common ; and on 

 the other hand, there are some animals which expel the membranes 

 quickly, conceive soon after, but again abort as readily — perhaps three 

 times in the course of a year. 



The foetus is usually dead, though when it is expelled (in the Cow) 

 after the fifth month it may be alive ; but it is weakly and soon dies, 

 even when born near the termination of pregnancy. These Calves make 



