DAIRY FARMING — DAIRYING. 1017 



but uot to milk fat. This agrees with the investigations of Kiibn and 

 Stohniann. Likewise, increasing tlie amount of protein in the ibod 

 resulted in an increase in the milk production or i)revented a shrinkage 

 with advancing lactation, but gave no one-sided increase in the fat con- 

 tent. The fat content was practically the same when 4 lbs. of rice 

 gluten containing 71 per cent of protein was fed as when hay was fed 

 alone. The addition of fat to hay materially increased the fat content 

 of the milk, provided the fat was in form to be taken up and digested. 

 When sesame oil, linseed oil, or tallow was added to the ration, in the 

 form of emulsions thoroughly mixed with the drinking water, the milk 

 contained as high as o.S per cent of fat. When 1,;") to -5 lbs. of linseed 

 oil was added to 18 to 22 lbs. of hay the millc averaged 5.24 per cent of 

 fat for 4 days; when 1 to 2 lbs. of tallow was added to the same amount 

 of hay the milk contained from 4.24 to 5.5 ])er cent of fat, the average 

 for S days being 4.7 i^er cent. 



This is contrary to the results of experiments by M. Fleischer, G. 

 Kiihn, and Stohmann. In the latter cases the addition of oil resulted 

 in a slight decrease in the fat, while in the present case it resulted in a 

 material increase in the fat content of the milk. This may be explained 

 by the fact that formerly the oil was mixed with the fodder, in which 

 form it is not digested and causes a disturbance of the digestive 

 functions. 



In Fleischer's experiment the addition of 4 lbs. of flaxseed resulted 

 in no increase in milk tat because the fat is not digested from whole 

 flaxseed. But in Stohmann's experiment, in which ground flaxseed 

 extracted of fat was fed in place of fat linseed cake, the fat content of 

 the milk decreased from O.G to 1 per cent. This is believed to furnish 

 a striking illustration of the eftect of a ration poor in fat as compared 

 with one rich in fat. This experiment, made in 186G, has previously 

 been overlooked in discussing this question. 



In feeding a ration rich in fat the author believes that the increase 

 in fat content of the milk does not take place by a transmission of the 

 fat of the food to the milk. With such feeding the content of volatile 

 fatty acids in the milk fat decreased in some cases nearly one half. For 

 instance, the Meissl number droi)ped from 25.32 to 15.7 when 10 lbs. 

 of hay and 2 lbs. of .sesame oil were fed; and the fat in the milk from 

 cows which were fed GO to 05 liters of corn distillery slop showed only 

 15.5 per cent volatile fatty acids. From this it might be concluded 

 that the sesame oil and corn oil, which are nearly free from volatile 

 fatty acids, were transmitted to the milk; but if this had been the case 

 the melting point of the butter made iVom this milk would have been 

 nmterially decreased. On the contrary, it was considerably incicased, 

 being 41.5°, as compared with the average melting point of butter of 

 30O, while that of the oils is below <P. 



As the result of the author's experiments, as well as of the examina- 

 tion of milk from herds to which large amountsof corn-distillery refuse 



