Sporadic or Accidental Abortion 467 



abortion. Even if the fetus should become infected late in ges- 

 tation, be born alive and comparatively vigorous though suffer- 

 ing from the infection acquired while in the uterus, and finally 

 overcome the effects of the disease and live, we should still speak 

 of it as infectious abortion. Thus, in speaking of abortion in 

 domestic animals, we include a variety of conditions, which it is 

 difficult to include under one definition. 



We recognize three classes of abortion in domestic animals : 



1. Sporadic or accidental abortion, in which, owing to disease 

 of, or accident to, the fetus or mother, the fetus may be expelled 

 dead or in a state of disease which renders it impossible for it to 

 live. 



2. Enzootic abortion, due to some infectious disease of the 

 mother, which brings about the death and expulsion of the fetus 

 as a complication of the maternal disea.se. 



3. Infectious abortion — an infection of the fetus and its mem- 

 branes which cau.ses the death and expulsion of the fetus or its 

 expulsion in a living and enfeebled state at an)- period of gesta- 

 tion from the date of conception to the normal completion of 

 pregnancy, without directly inducing material evidence of dis- 

 ease in the mother. 



I. Sporadic or Accidental Abortion. 



Any di.sease of the mother may more or less remotely involve 

 the well-being and safety of the fetus and may bring about its 

 death. Some infectious di-seases cause the death of a large per- 

 centage of fetuses. These we shall consider under enzootic abor- 

 tion. Clinically, illness of the pregnant female does not as a 

 rule seriously imperil the life of the fetus. Animals in various 

 stages of gestation, suffering from high fevers and a great variety 

 of disorders, if they recover, usually carry the fetus safely. 



Painful diseases of the digestive canal, accompanied by severe 

 tympany with exalted intra-abdominal pressure, may bring about 

 abortion, but in the vast majority of cases do not do so. 



The toxic effects of various drugs, especially of those which 

 have some special effect upon the genito-urinarj' organs, are 

 claimed to sometimes produce abortion. But we do not as a rule 

 observe such effects from these drugs. Harms asserts that he has 

 frequently administered aloes to pregnant mares without observ- 

 ing ill-effects, but that, when he gave an aloetic purge to a mare 



