DISEASES OF YOUNG CALVES. 263 



the action of the gastric juice on the casein, and with the interruption 

 of the natural stomach digestion the fats themselves undergo decom- 

 position with the production of offensive and irritating fatty acids. 



The milk of the very young cow is usually more watery than that of 

 the mature animal, and that of the old cow has a greater liability to 

 become acid. It varies much with the breed, the Channel Island 

 cattle being notorious for the relatively large amount of cream, while 

 the Holsteins, Ayrshires, and Shorthorns are remarkable rather for 

 the amount of casein. The milk of cows fed on potatoes and grass is 

 very poor and watery; that from cows fed on cabbage or Swedish 

 turnips has a disagreeable taste and odor (from the former an offen- 

 sive liquid has been distilled). 



Cows fed on overkept, fermented, and soured rations have acid 

 milk which readily turns and coagulates. Thus old long-kept brew- 

 er's grains, swill, the refuse of glucose factories, and ensilage which 

 has been put up too green, all act in this way. The same may come 

 from disease in the cow's udder, or any general disease of the cow 

 with attendant fever, and in all such cases the tendency is to rapid 

 change and unwholesomesness. If the milk is drawn and fed from 

 a pail there is the added danger of all sorts of poisonous ferments 

 getting into it and multiplying; it may be from the imperfect cleans- 

 ing and scalding of the pail; from rinsing the pails with water that 

 is impure; from the entrance of bacterial ferments floating in the 

 filthy atmosphere of the stable, or from the entrance of the volatile 

 chemical products of fermentation. 



In addition to the dangers coming through the milk, the calf suffers 

 in its digestive powers from any temporary illness, and among others 

 from the excitement attendant on the cutting of teeth, and impaired 

 digestion means fermentations in the undigested masses and the 

 excessive production of poisonous ptomaines and toxins. 



Whatever may be the starting or predisposing cause of this malady, 

 when once established it is liable to perpetuate itself by contagion and 

 to prove a veritable plague in a herd or a district. 



SyTiiptoms. — The symptoms of a diarrhea may appear so promptly 

 after birth as to lead to the idea that the cause already existed in the 

 body of the calf, and it usually shows itself before the end of the 

 second week. It may be preceded by constipation, as in retained 

 meconium, or by fetid eructations and colicky pains, as in acute indi- 

 gestion. The tail is stained by the liquid dejections, which are at 

 first simply soft and mixed with mucus with a sour odor, accom- 

 panied by a peculiar and characteristic fetor (suggesting rotten 

 cheese), which continually grows worse. The amount of water and 

 mucus steadily increases, the normal predominance of fatty matters 

 becoming modified by the presence of a considerable amount of undi- 

 gested casein, which is not present in the healthy feces, and in acute 



