336 FEEDING ANIMALS. 



the use of a highly carbonaceous food; and thus it was 

 proved that special feeding might change the proportion of 

 the constituents of milk. In the experiment we have 

 given, in developing the two cows by special feeding, an 

 increase in the element of butter, in the same cow, of about 

 18 per cent, is shown after long feeding ; proving that the 

 German experiments were too short to determine the effect 

 of special feeding. These experiments seem to have been 

 conducted on the theory that the constitution of the cow 

 is exceedingly flexible, if 14 to 30 days could very materi- 

 ally change the proportion of the secretions. In all these 

 experiments the ration of meadow hay furnished all the 

 elements of milk in the normal proportions, and it could 

 not reasonably be expected that additional food, rich in 

 either albuminoids or carbo-hydrates, could change the pro- 

 portion of the elements m milk, except in a long course 

 of feeding. A steady course of special feeding will work a 

 gradual but sure change. In confirmation of this, let us 

 present a large experiment, carried on for several years, and 

 giving most conclusive proof of the increase of oil, or but- 

 ter, in .the milk. The Hon. Zadock Pratt, of Greene 

 County, N. Y., reports to the New York State Agricultural 

 Society, the yield of his 50 cows for five consecutive years, 

 beginning with 1857 and including 1861. The first year it 

 required 39.2 pounds of milk for 1 pound of butter; the 

 second, 33.3 pounds ; the third, 29 pounds ; the fourth, 23.3 

 pounds ; the fifth, 21 pounds. The amount of butter per 

 cow per year increased in the same proportion. This herd 

 was made up of so-called " native cows," and consisted sub- 

 stantially of the same animals, there being only the ordi- 

 nary changes in such a herd. In 1862 he reports 64 cows, 

 many of them heifers, yet requiring only 19. 7 pounds of milk 

 for 1 pound of butter; his average of butter per cow reach- 

 ing 223 pounds. The next year, with 82 cows, he reached 

 an average of 224 pounds of butter per cow. He was con- 



