96 STORRS AGRICULTURAL EXPERIMENT STATION, | 
The uncertainty which was indicated in the statements just 
quoted and which still exists in the minds of many experiment- 
ers is expressed by Prof. Soxhlet of the Experiment Station at 
Munich, Germany, who has been lately experimenting upon 
the subject. The following is a brief 7éswmé of Prof. Soxhlet’s 
statements and experiments:* 
‘‘ As compared with feeding hay alone, hay and an easily digestible carbo- 
hydrate gave a milk poorer in fat. When the hay ration remained practically 
the same, but large amounts of starch were fed in addition, there was no appre- 
ciable increase in the milk yield, but a noticeable decrease (about .7 per cent.) 
in the fat. Fourteen pounds of starch was fed with sixteen pounds of hay, the © 
starch being treated with malt and given as a sweet drink. The starch is prob- 
ably changed to body fat, but not to milk fat.} This agrees with the investiga- 
tions of Kithn and Stohmann. Likewise, increasing the amount of protein in 
the food resulted in an increase in the milk production or prevented a shrinkage 
with advancing lactation, but gave no one-sided increase in the fat content, The 
fat content was practically the same when 4 pounds 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 drink- 
ing water, the milk contained as high as 5.8 per cent. of fat. When 1:5 toe 
pounds of linseed oil was added to 18. to 22 pounds of hay the milk averaged 
5.24 per cent. of fat for 4 days; when 1 to 2 pounds of tallow was added to the 
same amount of hay the milk contained from 4.24 to 5.5 per cent. of fat, the 
average for 8 days being 4.7 per 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 pounds of flax seed resulted in no 
increase in milk fat, because the fat is not digested from whole flax seed. But 
in Stohmann’s experiment, in which ground flax seed extracted of fat was fed in 
place of fat linseed cake, the fat content of the milk decreased from .6 to I per 
cent. This is believed 'to furnish a striking illustration of the effect of a ration 
poor in fat as compared with one rich in fat. This experiment, made in 1866, 
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 Meiss! number 
dropped from 25.32 to 15.7 when 16 pounds of hay and 2 pounds of sesame oil 

* Hxperiment Station Record, Vol. VIII., p. 1016. 
{ The late experiments by Prof. Jordan and his associates at the New York State 
Experiment Station, referred to on page 89, imply that milk fat is formed from the 
carbohydrates of the food. 

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