DOMESTIC ANIMALS 251 



cow should have six times as much carbohydrates as protein. This 

 is usually expressed in the form of a ratio, one to six, or i : 6, called 

 the 'nu'tritive ratio.' 



As a cow's stomach is large, she needs much bulky food, about 

 twenty-seven pounds of dry matter in a ration. In winter she 

 should have good hay, and in summer soiling or pasturage should 

 provide green forage. Turnips and other root crops should be 

 fed chopped or sliced. They should be given directly after milk- 

 ing so as not to injure the flavor of the milk. 



Filth injures the quality of all dairy products. Cleanliness, 

 fresh air, dryness, and sunshine kill bacteria which injure the 

 health of the cow and affect her products. The stable should be 

 clean, comfortable, and well ventilated. The cow's udder and the 

 body near it should be washed, and milking should be done with 

 clean dry hands. 



Milk should never be left standing in a stable or milkroom, where 

 the air is impure. It readily absorbs flavors and should not be 

 kept near cabbage, onions, or any other highly- flavored foods. 

 All vessels used about milk should be washed in cold water and 

 then scalded with boiling water. They should often be sunned 

 and aired. 'Cleanliness should be the watchword of the dairy.' 



The cow should be fed and milked at regular hours and always 

 treated with kindness. She is a nervous animal, and tests show 

 that the quality and quantity of her milk are injured by rough, 

 harsh treatment. " 



Diseases. Tuberculosis. The most common and dangerous dis- 

 ease of dairy cattle is tu ber cu lo'sis. It is caused by bacteria in 

 the affected part of the body ; these form tubercles, swollen masses 

 of tissue, which finally break down into a cheesy mass. Some 

 scientists say that the disease can be communicated to human 

 beings from the milk and the flesh of diseased animals. By boiling 



