110 MANUAL OF FARM ANIMALS 



derangement of the female organs, diseased ovaries, tumors, and 

 the like. 



Abortion in mares. — Abortion is the expulsion of the fetus 

 at any period from the date of impregnation until the foal can 

 survive out of the womb. It is produced by any cause operating 

 to disconnect the union of the fetal membrane from the uterus. 

 The mare may abort by reason of almost any cause that very 

 generally disturbs her system, as the influence of too stimulating 

 diet or the reverse, wet seasons, a previous miscarriage, and 

 all circumstances opposed to efficient nutrition and respiration. 

 The more direct mechanical causes are falls, blows, violent 

 exertion, severe illness, large draughts of cold water or eating 

 iced grass, ergot of rye, the smut of corn or other grain, and 

 drinking filthy stagnant water ; also, traveling on heavy muddy 

 roads, soft plowed ground, or jumping over fences, ditches, and 

 the like. 



The prevention of abortion is the avoidance of all causes which 

 may have a tendency to produce it. When abortion has once 

 occurred, the greatest care in subsequent management is neces- 

 sary. The breeder must avoid all causes of constipation, 

 diarrhea, indigestion, and the hke. When all measures fail and 

 miscarriage results, all that can be done is to assist in the removal 

 of the fetus and its membranes as in ordinary parturitions. 

 The mare should have extra care at this time. She should have 

 a roomy, well-lighted stall, with plenty of air and easily digested 

 food. The mare should not be served again for a month or 

 longer, and in no case till after all discharges from the vulva 

 have ceased. 



Parturition time. — The average period of gestation in the 

 mare is popularly placed at eleven months, more accurately 

 perhaps three hundred and forty days, but it may vary greatly. 

 (See page 108.) Because of the uncertainty of the period, the mare 

 should be closely watched from the tenth month till parturition. 

 There are certain signs of the near approach of parturition that 



