124 MILK 



tions the quantity of milk gradually diminishes and the quality 

 suffers. 



As shown previously, each breed of cows produces milk of 

 characteristic composition. Furthermore, some breeds are known 

 to be large producers, others the reverse. It has also been noted 

 that individual cows differ in the quantity and quality of milk 

 produced. This shows that quantity and quality are determined 

 by breed and individuality, and authorities are now of the opinion 

 that it is impossible to materially and permanently alter the milk 

 of a given breed or individual. The influence of food upon nulk 

 production becomes apparent when underfed cows are dealt with, 

 or those that have received improperly balanced rations. This 

 has been borne out by a large number of trustworthy observations. 

 When a poorly or injudiciously fed herd is placed on a well-bal- 

 anced ration milk production is increased and the quality improved. 

 But this change cannot go beyond the limit which the breed or 

 individual is capable of producing. 



Wing and Foord cite an experience with a herd whose produc- 

 tion was increased 50 per cent. The fat increased | of 1 per cent. 

 This was accomplished by feeding properly balanced rations in 

 suitable quantity. Fraser has shown that on a balanced ration 

 of a 1:6 ratio 6 cows produced as much milk as 9 on a 1 : 11 

 ration. 



The "nutritive ratio" expresses the relation of protein to car- 

 bohydrate and fat. The sum of the weight of digestible carbohy- 

 drate plus two and one-fourth times the weight of digestible fat 

 is divided by the weight of the digestible protein in the food. The 

 result is the nutritive ratio. Investigations have shown that pro- 

 tein furthers milk flow and improves the quaUty. Woll therefore 

 argues that a narrow ratio leads to higher milk production than a 

 wide ratio. He suggests a standard of 2.15 pounds protein for 

 1000 pounds of body weight with sufficient fat and carbohydrate 

 to make the nutritive ratio 1 : 6.9. Beach's experience leads him 

 to advocate 2.5 pounds protein and a ratio of 1 : 5.6. Wheeler 

 found that narrowing the ratio had a favorable effect upon milk 

 production, while widening it tended toward the reverse. 



The kind of food given is not a matter of indifference. Digest- 

 ibility and the presence of water must be considered. Dry fodder 

 does not further milk flow as well as succulent food, but moisten- 

 ing the food will not take the place of giving fresh, succulent fodder. 

 It follows that a change from the stable to pasture in early spring 

 increases the milk flow and the content of solids. 



However, other conditions unquestionably aid in increasing 

 the milk flow from cows that are turned into the pasture after 

 having spent the winter in a stable. Exercise, fresh air, and sun- 



