First and Last Milk Drawn. 29 
There is also a considerable variation in the 
milk from day to day. This is usually not so 
great as between the morning and evening milking, 
but it not infrequently amounts to 1 per cent. 
Such daily variations may be ascribed to changes 
in the climate or other environment of the cows,— 
the effect of storms, the effect of change of food, 
the effect of slight indispositions, ete.; but there 
are numerous conditions not usually or readily 
recognized by the owner that affect the composition 
of the milk. It has been noted in many instances 
that the normal effect of a slight febrile condition 
of the animal is to largely increase the percentage 
of fat and albumin. If the febrile condition con- 
tinues, and particularly if it grows more severe, 
the fat then falls as quickly as it had risen, and 
to a correspondingly lower point. 
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 
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