114 PRINCIPLES AND PRACTICE OF MILK HYGIENE 



INDIGESTION 



When the digestive functions of the dairy cow are 

 disturbed, as in gastro-intestinal catarrh, there is not 

 only a decrease in the quantity of milk secreted, but quite 

 frequently the milk has a bitter or salty taste and coagu- 

 lates prematurely (six to eight hours after milking) . It 

 contains less fat than normal milk and sometimes appears 

 thinner and of a yellow color. Milk from cows in this 

 condition may possess irritant properties and when in- 

 gested unmixed with the milk of other cows may produce 

 diarrhoea, especially in children. 



The milk may undergo similar changes in other in- 

 ternal diseases which do not directly involve the udder. 



Spoiled Feed. The milk of cows fed on mouldy, 

 fermented, or putrefied feed has produced diarrhoea in 

 persons ingesting it. This effect has been attributed to 

 the elimination in the milk of abnormal substances con- 

 tained in such feeds, but it is possible that the organisms 

 causing the changes in the feed may have gained access 

 to the milk during milking and caused changes in the milk 

 itself which brought on the diarrhoea. 



SEPTIC OR HEMORRHAGIC ENTERITIS 

 This disease consists of a severe or bloody diarrhoea 

 associated with a high temperature and other constitu- 

 tional disturbances. It may occur sporadically or en- 

 zootically, especially among young cattle. According to 

 Jensen, it is caused by bacteria of the paracolon group 

 which circulate in the blood and which are also present 

 in large numbers in the fecal discharges. Secondary in- 

 fection of the milk during milking is almost certain to 

 occur since the udder, thighs, and flanks of the diseased 

 animal will be soiled by the fecal matter. The bacteria, 



