30 Milk and Its’ Products 
The variation in the percentage of fat in the 
milk first and last drawn is very great.. The first 
milk drawn is much the poorer in fat. Differ- 
ences so wide as 1 and 10 per cent of fat in 
the first and last few pints have not infrequently 
been noticed. This is due in large measure to the 
fact that the larger globules of fat, being of 
nearly the same size as the smaller milk ducts, 
pass along these vessels less readily than the more 
fluid portions of the milk, and are only drawn 
out with the last milk drawn. The milk first 
drawn has been in the milk cisterns and larger 
vessels for a considerable period of time, and so 
has been subject to the reabsorptive action of the 
lymphatics for a longer time, which also would 
tend to make it poorer in fat. 
The food also has a considerable influence upon 
‘the quality of the milk, although the quantity of 
the milk is more easily affected by changes in the 
amount and character of the food than is quality. 
In fact, with cows kept under favorable conditions, 
with an abundant supply of food, it is hardly 
possible to increase the proportion of fat to other 
solids by a change in the food. On the other hand, 
while the amount of the various constituents of 
the milk is not easily affected by the food, the 
quality of the constituents themselves may be 
considerably influenced, notably in the case of the 
fat. Certain foods have a marked influence upon 
the character of the milk fat. Thus linseed meal, 
gluten meal and certain other foods make a soft, 
