38 Milk and Its Products 



to four weeks before calving, than though she is 

 milked right up to calving, as often may be done. 

 So far as can be ascertained, the good effect of this 

 dry period is very largely physiological, the secreting 

 glands in the udder are stimulated to greater activity 

 by reason of having been inactive for a. short space. 

 While dairymen often speak of this period of dry ness 

 as a resting period, its good effect is probably not 

 so much due to the resting of the general vital 

 powers of the animal as to the physiological con- 

 dition of the udder itself. 



In most cows when the period of pregnancy has 

 reached about the seventh month, there is a marked 

 diminution in the flow of milk, and the udder shrinks 

 rapidly in size. If now regular milking ceases, the 

 cow soon "dries up," the udder shrinks away and 

 becomes flaccid and empty, except for a small amount 

 of watery saline fluid. About two weeks before par- 

 turition, the udder begins to take on renewed activity. 

 It increases rapidly in size, but remains soft and spongy 

 under normal conditions until a very short time 

 before calving. If the cow is very fat, if she is 

 fed heavily on stimulating, heating foods, or if there 

 are other conditions that tend to plethora of the body, 

 the swelling of the udder may be unduly large, take 

 on an inflammatory character, and the udder becomes 

 caked. In cows of a heavy milking habit this often 

 is a very serious condition, and may even destroy 

 the usefulness of the animal, or at least one or more 

 quarters of the udder. It is obviated by taking care 

 that the animal is fed only loosening and cooling 



