A CCIDENTS OF PREGNA NCY. 211 



matter from the expelled membranes of one which has been delivered, 

 abortion can be induced. 



So that, says Zundel, it is sufficient to introduce into the vagina 

 micrococci or bacteria, which multiply there, and, penetrating to the 

 uterus, commence their work of decomposition, of which abortion is the 

 consequence.' 



Roloff has also ascertained that abortion is due to something which 

 finds admission to the uterus by the vagina ; that a certain amount of 

 . redness and tumefaction of the lining membrane of the latter always 

 precedes this accident ; and that this viruliferous or miasmatic matter is 

 found on the articles soiled by the delivery of a Cow which has aborted, 

 as well as in the drains of the stable, on the litter, etc. 



It has been remarked that, in general, the foetal membranes are liable 

 to be retained in Cows which abort, and that when not removed 

 artificially, they only come away when decomposition sets in. The 

 influence of these putrefying membranes has been noted by several 

 veterinarians — Pele, Barrier, Cruzel, Bouley, Rychner, 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 mem- 

 brane. In support of this opinion, he quotes the observations of Roloff, 

 who asserts that he always saw the disease or accident developed in 

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

 where the drains did not have sufficient fall, whereby the hind quarters of 

 the cattle were readily soiled by the excreta in them. 



Without, then, going further into the question, and without taking into 

 consideration other agencies which may cause extensive abortion — such 

 as ergotized grasses — it may be concluded that this kind of miscarriage 

 is transmissible through the medium of some infectious or virulent 

 principle, which is really specific in its nature : for it is not necessarily 

 allied to putrefaction of the foetal membranes ; and it always produces 

 the same effect — abortion — without any other apparent efficient cause 

 being in opertion. 



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 symp- 

 toms, except perhaps a trifling uneasiness for a few hours previously, 

 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 rup- 

 tured membranes are rejected immediately after the foetus ; as a rule 

 they are nearly always retained, particularly when gestation is advanced ; 

 and they putrefy in the uterus, being got rid of only in shreds at 

 intervals. Then the animal loses its appetite and condition, goes off its 

 milk, and sometimes perishes, as a consequence of this placental re- 

 striction. If it recovers, oestrum appears unnaturally often, though con- 

 ception is unfrequent and sterility common ; and on the other hand, 

 there are some animals which expel the membranes quickly, conceive 

 •soon after, but agaii* abort as readily — perhaps three times in the 

 course of a year. 



