Tumors of the Mamma' 981 



It is not essential, usually, that any active handling occur. 

 As soon as lactation has become well established and the young 

 sucks regularly, or the gland is well milked out, the edema spon- 

 taneously disappears. If, however, the young dies or has been 

 removed, and it is not desired to keep up the lactation for the 

 production of milk, it is advisable and frequently essential that 

 a portion of the milk should be withdrawn two or three times a 

 day, until the activity of the gland becomes diminished. If 

 less and less of the milk is withdrawn each day, the lactation 

 gradually ceases, and the milking may be discontinued gener- 

 ally within five or six days. Most domestic animals are thus 

 easily dried up, though in some instances there is considerable 

 difficulty, especially in the milk cow. In some of the best dairy 

 animals it is almost impossible to stop the secretion of milk with- 

 out endangering the integrity of the gland. This difficulty is 

 also observed at times in ewes, when weaning lambs, espe- 

 cially if they are weaned somewhat early, before the milk glands 

 have largely ceased their functions. In some of the larger breeds 

 of sheep, which are very heav}^ milkers, it is well to carefully 

 watch the ewes while the lambs are being weaned, and withdraw 

 part of the milk from those which show very great distension 

 of the gland with the consequent edema. 



14. Tumors of the Mamm.^. 



Tumors of the mammary glands are very rare in domestic 

 animals, with the exception of the bitch, in which they are com- 

 mon. Ruminants are almost wholly free from any form of mam- 

 mary tumor. In the mare we observe chiefly the botryomycotic 

 udder, which has already been described upon page 974, and 

 belongs distinctly to infections, not to tumors proper. The 

 bitch suffers occasionally from a form of granulation tumor or 

 adeno-fibrom, in which the general characters of adenoma and 

 fibroma are combined. Such adeno-fibroma are usually the 

 sequel of infection. 



The adeno-fibrom consists chiefly of an increase of the con- 

 nective tissue between the lobules of the gland, which new-formed 

 tissues press upon the acini and gradually bring about their de- 

 struction, until there remains simply the epithelial debris sur- 

 rounded bv firm connective tissue. 



