90 Veterinary Elements. 



bone, to be eventually united to the internal thoracic 

 vein (the mammary vein of the human). 



The mammary vein then will be accepted as affording 

 some indication at least of the milking capabilities of a 

 cow. Some breeders' associations call for certain ar- 

 rangements of those veins, as follows: Single and double 

 extension, single and double branches, single and double 

 chest extension, or umbilical (navel) veins. The wells 

 vary in number from one to three on each side of the 

 animal; they should be of good size. 



The greater the capacity of the arteries and veins con- 

 nected with the udder, the larger the milk secretion will 

 usually le. Theory and practice then seem to unite 

 and back up the ideals of the dairyman, one of which is 

 a great development of the mammary veins. The arte- 

 rial supply cannot be seen, and only parts of the venous 

 system of the udder are visible, viz., the abdominal veins 

 and those underlying the skin of the udder, yet reason- 

 able conclusions can be drawn from the development of 

 the 'milk veins. 



Holding up the Milk. Various theories have been ad- 

 vanced to account for this illustration of animal per- 

 versity and human peculiarity; the latter probably had 

 been shown in the form of abuse, and of course, stamps 

 the exhibitor as one not fit to own or milk cows. Wing, 

 in ' * Milk and Its Products, ' ' states that the holding of 

 the milk is due to the presence of sphincter muscles at 

 the branching of the ducts, and that this muscular tissue 

 is connected with the abdominal muscles, which if con- 

 tracted, as a result of fright, dislikes, etc., will cause 

 the milk to be retained in the udder, or as it is termed 



