MILK AND ITS CARE. 173 



aiuouiit of milk, followed b)' the Ayrshire, Guern- 

 sey, and Jersey. 



2. Individuality. — The difference between in- 

 dividual animals in the same breed is greater 

 than the average difference betw^een breeds, 

 both as to quality and quantity of milk pro- 

 duced. This factor should be given first con- 

 sideration in estimating the value of an animal 

 for dairy purposes. 



3. Period of Lactation. — By period of lacta- 

 tion is meant one complete milking period, 

 usually from nine months to one jear. A cow, 

 as a rule, produces the most milk per day within 

 a month after the calf is born, and gradually de- 

 creases in amount until the secretion ceases. 

 The lowest per cent, of butter fat usually is 

 found at the time of greatest production, and 

 increases somewhat as the flow of milk de- 

 creases. 



4. Feed. — The kind and amount of feed have 

 great influence on the quantity of milk pro- 

 duced, but have no effect on the per cent, of 

 butter fat, although it is believed otherwise by 

 many dairymen. The richness of a cow's milk 

 is as natural to her as is the color of her hair, 

 and is affected about as little by change of 

 feed. 



5. External Conditions. — Many other things 

 affect the quality and the amount of milk se- 

 creted — as, treatment by milker, change of 



