4 Milk and Its Products. 



udders are more subject to inflammations and in- 

 flammatory diseases than those with less fatty tissue. 

 In many cows the fibrous net -work that supports 

 the udder is held firmly up to the under side of the 

 abdomen. If, in connection with this, the udder has 

 comparatively little connective and fatty tissue, the 

 animal will have an udder apparently small, but with 

 large capacity for secretion. In old cows, particu- 

 larly those that have been large milkers, the fibrous 

 bands often become largely relaxed, so that the 

 udder falls nearly to the ground, and appears to be 

 of enormous size. 



Internal structure of the udder and teats. — The 

 teat is simply a canal surrounded by muscular walls 

 and closed at the extremity bj^ an involuntary 

 sphincter muscle, which varies much in rigiditj^ in 

 different animals ; often it is so lax that the pressure 

 of a small amount of milk in the canal is sufficient 

 to open it and the animal leaks her milk. In other 

 animals it requires a strong effort of the hand to 

 draw the milk. When desirable, the rigidity may be 

 overcome by keeping a smooth wooden plug of suf- 

 ficient size to moderately dilate the opening in the 

 end of the teat till the muscle relaxes sufficiently 

 to permit easy drawing of the milk, or the muscle 

 may be partially divided with the knife in the 

 hands of a skilful operator. At the top of the 

 teat, or bottom of the udder, there is a small 

 cavity known as the milk cistern, serving to hold 

 the milk after its secretion until it is drawn. 

 It is of varying capacity, up to half a pint, 



