76 VETERINARY STUDIES 



udder and teats are rather common, and become serious by 

 reason of infection. Ohstructions in the teat duct involve the 

 mucous membrane and appear in the form of small tumors or 

 local membranous obstruction or as a general thickening of this 

 membrane. 



Many of these cases can be cured by a veterinary operation. 

 Abscess, due to infection, may destroy a considerable amount of 

 gland substance and is treated by external drainage and sur- 

 gical cleanliness. Cowpox affects the skin of udder and teats 

 and resembles smallpox. It is usually spread by the milker's 

 hands. Upon the udder where not broken and irritated by the 

 milker's hands, there is first a sort of blister, the contents of 

 which later change to yellowish pus, thin scab, and finally a 

 pitted scar for each blister. 



Suppression of milk may result from ill health, lack of nutri- 

 tion, or general disease of the udder, and there appears to be a 

 suppression of bacterial origin, apparently infectious. 



See Udder Diseases and Accidents, Lecture LVI. 



