332 MANUAL OF FARM ANIMALS 



Cattle are particularly subject to a contagious form of abortion 

 which destroys many young before they can live out of the womb. 

 The principal diseases or difficulties are barrenness; abortion, 

 both contagious and non-contagious; difficult parturition; re- 

 tention of the afterbirth; milk-fever; garget. 



Barrenness in cows. — It often happens that cows are served 

 normally, yet fail to conceive. Some of the causes of this diffi- 

 culty are readily understood and easily prevented, while others 

 are not well understood and are beyond control of the breeder. 

 An excess of rich and stimulating foods is a common cause of 

 non-breeding, especially if the animals are denied exercise. 

 The dangers attending parturition are often more than tre- 

 bled in the case of fat animals. This excessive fat, however, 

 may be of much advantage once these dangers are past. On the 

 other hand, barrenness may be due to poor feeding, the system 

 being weakened by the lack of sufficient nutrition. Undue 

 sexual excitement at the most active stage of heat is often 

 responsible for the cow not conceiving. Cows that for some 

 reason have missed a season are often difficult to impregnate. 

 Animals that are too closely inbred are also likely to be 

 barren. In addition to these, there is a long line of causes of 

 barrenness in cows over which the breeder has little or no con- 

 trol, such as derangement of the sex organs, diseased ovaries, 

 tumors, and the like. 



Abortion in cows. — Abortion in cows is either contagious or 

 non-contagious. Because of the great differences as to cause 

 and subsequent treatment, we consider them separately. 



Non-contagious abortion. — This is produced by any cause 

 operating to disconnect the union of the fetal membrane from the 

 uterus. A cow may abort by reason of almost any cause that 

 very generally disturbs her system, as from the influence of a too 

 stimulating diet or the reverse, as when the nourishment is so 

 deficient that the fetus dies in the womb; damp, unhealthy 

 stables ; worms in the bowels, lungs, or liver ; indigestion of all 



