62 AGRICULTURAL EXPERIMENT STATION. [Jan. 



One cannot fail to note the variations in the composition 

 of the milk obtained in the different series. The percentage 

 increase or decrease in the per cent, of total solids is rela- 

 tively small, being in most cases from 5 to 3 per cent. The 

 percentage variations in the per cent, of fat, on the other 

 hand, are much wider, in some cases as high as 16 per cent, 

 or more being noted. With some of the cows, in cases 

 where more protein was fed, the percentage of solids not fat 

 shows a steady decrease, the fat, on the other hand, increas- 

 ing even more, showing that the solids not fat were somewhat 

 depressed at the expense of the fat. With other cows this 

 variation in solids not fat was very slight. 



Series I, a and h. 



In Series I. 5, when but 1.30 pounds of digestible protein 

 were fed in the daily ration, the amount of fat in the milk is 

 noticeably lower than in Series I. «, when double tne amount 

 of protein was consumed daily. The percentage increase in 

 the per cent, of the fat in Series I. a is also high, varying 

 from 4 to 20 in case of the first five cows. 



The total solids were also increased in a, but to a much 

 less degree. 



The solids not fat showed a percentage of decrease in case 

 of the first three cows of some 6 per cent., and with the last 

 three a slight increase appeared. The ratio of fat to solids 

 not fat should by no means pass unnoticed. In case of the 

 first five cows, in a it was as 1 : 1.95, while in 5 as 1 : 2.36. 



The cows also difiered in what may be termed their sus- 

 ceptibility to the influence of the difierent fodder rations. 

 The percentage of fat increase in the milk in case of cows 

 Sarah and Nora was not so great as in case of the first three 

 cows ; while in case of Nellie the extreme food changes 

 seemed to have had a comparatively small influence on the 

 composition of the milk. The animal appeared, however, 

 to feel more than any of the other cows the bad efiect of the 

 improperly combined ration h. Her whole general appear- 

 ance told of a non-suitable food supply. This cow illustrates 

 quite clearly the fact that the composition of the milk of dif- 

 ferent cows can be differently affected by the same food com- 

 binations. Although she gave every appearance of receiving 



