DISEASES OF THE GENEEATIVE ORGANS. 165 



ABORTION (slinking THE CALf). 



Technically, abortion is the term used for the expulsion of the off- 

 spring before it can live out of the womb. Its expulsion after it is 

 capable of an independent existence is premature parturition. In the 

 cow this may be after seven and one-half months of pregnancy. Earl 

 Spencer failed to raise any calf bom before the two hundred and 

 forty-second day. Dairymen use the tenn abortion for the explusion 

 of the product of conception at any time before the completion of the 

 full period of a nonnal pregnancy, and in this sense it will be em- 

 ployed in this article. 



Abortion in cows is either contagious or noncontagious. It does not 

 follow that the contagium is the sole cause in every case in which it is 

 present. We know that the organized germs of contagion vary much 

 in potency at different times, and that the animal system also varies 

 in susceptibility to their attack. The germ may therefore be present 

 in a herd without any manifest injury, its disease-producing power 

 having for the time abated considerably, or the whole herd being in a 

 condition of comparative insusceptibility. At other times the same 

 germ may have become so virulent that almost all pregnant cows suc- 

 cumb to its force, or the herd may have been subjected to other causes 

 of abortion which, thougli of themselves powerless to actually cause 

 abortion, may yet so predispose the animals that even the weaker 

 germ will operate with destructive effect. In dealing with this dis- 

 ease, therefore, it is the part of wisdom not to rest satisfied with the 

 discovery and removal of one specific cause, but rather to exert one- 

 self to find every existent cause and to secure a remedy by correcting 

 all the harmful conditions. 



CAUSES OF NONCONTAGIOrS ABORTION. 



As abortion most frequently occurs at those three-week intervals 

 at which the cow Avould have been in heat if nonpregnant, we ma-y 

 assume a predisposition at such times due to a periodicity in the 

 nervous system and functions. Poor condition, weakness, and a too 

 watery state of the blood is often a predisposing cause. This in its 

 turn may result from poor or insufficient food, from the excessive 

 drain upon the udder while bearing the calf, from the use of food 

 deficient in certain essential elements, like the nitrogenous constitu- 

 ents or albuminoids, from chronic wasting diseases, from roundworms 

 or tapeworms in the bowels, from flatworms (flukes, trematodes) in the 

 liver, from worms in the lungs, from dark, damp, unhealthful build- 

 ings, etc. In some such cases the nourisliment is so deficient that the 

 fetus dies in the womb and is expelled in consequence. Excessive 

 loss of blood, attended as it usually is by shock, becomes a direct 

 cause of abortion. 



