634 IOWA DEPARTMENT OF AGRICULTURE. 



The excitement, jarring, and jolting of a railroad journey will often 

 cause abortion, expecially as the cow nears the period of calfing, and 

 the terror or injury of railway or other accidents prove incomparably 

 worse. 



All irritant poisons cause abortions by the disorder and inflamma- 

 tion of the digestive organs, and if such agent act also on the kidneys 

 or womb, the effect is materially enhanced. Powerful purgatives or 

 diuretics should never be administered to the pregnant cow. 



During pregnancy the contract of the expanding womb with the 

 paunch, just beneath it, and its further intimate connection through 

 nervous sympathy with the whole digestive system, leads to various 

 functional disorders, and especially to a morbid craving for unnatural 

 objects of food. In the cow this is shown in the chewing of bones, pieces 

 of wood, iron bolts, articles of clothing, lumps of hardened paint, etc 

 An unsatisfied craving of this kind, producing constant excitement of 

 the nervous system, will strongly conduce to abortion. How much more 

 so if the food is lacking in the material matter, and expecially the phos- 

 phates necessary for the building up of the body of both dam and off- 

 spring, to say nothing of that drained off in every milking. This state- 

 of things is present in many old dairy farms, from which the mineral 

 matters of the surface soil have been sold off in the milk or cheese for 

 generations and no return has been made in food or manure purchased. 

 Here is the craving of an imperative need, and if it is not supplied the- 

 health of the cow suffers and the life of the fetus may be sacrificed. 



Among other causes of abortion must be named the death of the var- 

 ious illnesses of the fetus, which are about as numerous as those of the 

 adult; the slipping of a young fetus through a loop in the naval string 

 so as to tie a knot which will tighten later and interrupt the flow of blood 

 with fatal effect, and the twisting of the naval string by the turning of 

 the fetus until little or no blood can flow through the contorted cord. 

 There is in addition a series of diseases of the mucous membrane of the 

 womb, and of the fetal membranes (inflammation, effusion of blood, 

 detachment of the membranes from the womb, fatty or other degenera 

 tions, etc.), w'hich interfere with the supply of blood to the fetus or 

 change its quality so that death is the natural result, followed by abor- 

 tion. 



CAUSE OF CONTAGIOUS ABORTION. 



While any one of the above conditions may concur with the contagious 

 principle in precipitating an epizootic of abortion, yet it is only by rea- 

 son of the contagium that the disease can be indeflnitely perpetuated and 

 transferred from herd to herd. When an aborting cow is placed in a herd 

 that has hitherto been healthy, and shortly afterwards miscarriage 

 becomes prevalent in that herd and continues year after year, in spite 

 of the fact that all the other conditions of life in that herd remain the 

 same as before, it is manifest that the result is due to contagion. When 

 a bull, living in a healthy herd, has been allowed to serve an aborting 

 cow, or a cow from an aborting herd, and when the members of his own 



