TllK IvKLATlON OF FouD TO MiLK-FaT. 57 



richer in fat. He says nothing of the plan or extent of his experi- 

 ments and gives nothing but the conclusions and a discussion of 

 theories. As compared with hay alone, the addition of fourteen 

 pounds of starch, treated with malt and given as a sweet drink, 

 with sixteen pounds of hay made no ap})reciablc increase in milk 

 yield hut a noticeable decrease (about 0.7 per cent) in fat. The fat 

 content was practically the same when four pounds of rice gluten 

 containing 71 per cent of protein was fed as when hay was fed alone. 

 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 5.8 percent of fat. When 1.5 to 2 pounds 

 of linseed oil were added to 18 to 22 pounds of hay the milk 

 averaged 5.24 per cent of fat for four days ; when 1 to 2 pounds of 

 tallow were added to the same amount of hay the milk contained 

 from 4.24 to 5.5 per cent of fat, the average for eight days being 

 4.7 per cent. The author believes that the addition of oils to the 

 ration in the form of emulsions will increase the per cent of fat in 

 the milk while the addition of the same oils in other forms will not so 

 increase it, because the oils are more easily digested in the form of 

 emulsion. He does not believe that the fat of the food goes directly 

 into the milk, but that it forces the body fat, i. e. tallow, over into 

 the milk, and thus indirectly increases the quantity of milk fat. He 

 further states that the fat of the food alone, and not the protein or 

 carbohydrates, is capable of bringing about a one-sided increase in 

 the fat content of the milk. 



Beglarian * studied the effect of linseed oil, given in water as an 

 emulsion and of ground iiaxseed with four cows during four periods 

 of eight days each. The cows shrank in milk yield wliile taking the 

 oil ration and increased on the flaxseed ration. The author considers 

 the results entirely negative since the oil was not accompanied by an 

 appreciable rise in the fat content, while it had an unfavoraljle effect 

 on the digestion and comfort of the cows. The ground flaxseed had 

 no effect on the quality of the milk and a less unfavorable influence 

 on tlie animal's digestion. 



Holtsmark f found that feeding cows as much as 77 pounds of 



* Milch Zeituiig 26 (189T), p. 522. 



t Translation by F. W. WoU iu Experimeut Station Record, vol. l)(l«97), |>. 92. 



