206 DISEASES OF CATTLE, SHEEP, GOATS, ETC. 



BLUE MILK. 



"Watery milk is blue, but the presence of a germ (Bacillus cyano- 

 genes) causes a distinct blue shade even in rich milk and cream. 

 It may reach the milk after it has been drawn, or it may find its way 

 into the opening of the milk ducts and enter the milk as it is drawn. 

 In the latter case, frequent milking and the injection into the teats 

 of a solution of 2 drams of hyposulphite of soda in a pint of water 

 will serve to destroy them. 



STRINGY MILK. 



This may be caused by fungi developing in the liquid, and that 

 the spores are present in the system of the cow may be safely in- 

 ferred from the fact that in a large herd two or three cows only will 

 yield such milk at a time, and that after a run of ten days or a fort- 

 night they will recover and others will be attacked. I have found 

 that such affected cows had the temperature raised one or two de- 

 grees above the others. Like most other fungi this does not grow 

 out into filaments within the body of the cow, but in five or six hours 

 after milking the surface layers are found to be one dense network of 

 filaments. If a needle is dipped in this and lifted, the liquid is 

 drawn out into a long thread. In one case which I investigated near 

 Ithaca, N. Y., the contamination was manifestly due to a spring 

 which oozed out of a bank of black muck soil and stood in pools 

 mixed with the dejections of animals. Inoculation of pure milk 

 with the water as it flowed out of this bank developed in it the fungus 

 and the stringy characters. By fencing in this spring and giving 

 the affected cows each 2 drams bisulphite of soda daily, the trouble 

 was arrested promptly and permanently. 



BITTER MILK. 



Abnormal flavors in milk and milk products may be due to a 

 number of causes. It is well known that certain weeds eaten by 

 cows impart a characteristic flavor to the milk. Garlic or wild onion 

 is a very noticeable example. The Alabama Station succeeded in re- 

 moving the taste of bitterweed from cream (but not from milk) by 

 mixing the cream with two or more times it volume of warm water 

 and then separating again with a centrifugal separator. Proper at- 

 tention to the feeding of cows will, of course, prevent trouble of this 

 kind. 



In 1890 H. W. Conn, of the Connecticut Storrs Experiment 

 Station, isolated a species of bacteria from a sample of bitter cream 

 and showed experimentally that the organism was the cause of the 

 trouble. Several other investigators have also shown that bacteria 

 may be the cause of bitterness in milk. A bulletin of the Ontario 

 Agricultural College and Experimental Farm, by F. C. Harrison, 

 publishes some interesting observations on bitter milk. In this case, 

 however, the bitter flavor was caused by a form of yeast rather than 

 by bacteria. Numerous cheese factories in Ontario were annoyed by 

 the development of a bitter flavor in milk and curd. From a sam- 

 ple of such curd a yeast-like micro-organism designated Torula 

 amara, or bitter torula, was isolated. This yeast, when separated 

 from all other micro-organisms and added to milk which had been 



