256 DISEASES OF CATTLE. 



the interruption of the natural stomach digestion the fats themselves 

 undergo decomposition with the production of offensive and irritat- 

 ing fatty acids. 



The milk of the very young ccw 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 quantity of cream, 

 while the Holsteins, Ayrshires, and Shorthorns are remarkable rather 

 for the quantity 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, fermen ed, 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 unwholesomeness. 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 suf- 

 fers 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. 



Symptoms. — The symptoms of a diarrhea may ajopear 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 with a peculiar and characteristic fetor (suggesting rotten 

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

 mucus steadily increases, the normal predominance of fatty matters 

 becoming modified by the presence of considerable undigested casein, 

 which is not present in the normal feces, and in acute cases death 



