MAMMITIS. 701 



any good, though they serve to pacify the owner. If licked by the 

 cow or calf they may prove positively dangerous, and under any 

 circumstances are apt to enter the milk. 



Calculi sometimes form in the mammary gland or galactophorous 

 sinus. They consist chiefly of organic substances, but usually contain 

 a considerable quantity of phosphate of lime, form rounded masses 

 varying in size and number, though they are not often numerous, 

 and can be detected by palpation of the udder or teat. Those which 

 enter the teat can usually be removed by manipulation from above 

 downwards with the finger and thumb. Failing success by this 

 method the teat must be laid open at the base, the calculus removed, 

 and the wound closed by sutures. The parts (which should have 

 been carefully disinfected before operation) can then be thickly 

 painted with iodoform collodion, or sublimate gelatine. Calculi 

 which do not enter the teat seldom prove troublesome. 



(2.) MAMMITIS. 



Authors have adopted the most varying views as to the origin 

 and classification of the various forms of inflammation of the udder, 

 some based on anatomical, others on clinical and pathological grounds. 

 All of these have some justification, but none equally satisfies the 

 practitioner and the scientist. In practice it is difficult and often 

 impossible to distinguish between an interstitial and a parenchymatous 

 mammitis ; generally the whole gland is invaded at the end of a 

 few days, whatever the point of origin, and the inflammation is 

 therefore of a mixed character. During lactation acute inflammation 

 of the udder is most common, especially in animals that are kept 

 for the purpose of producing milk (cow, goat, milch ewe), but is 

 rare in those in which the mammary function is limited to the 

 nourishment of the young. Guillebeau says that cows most frequently 

 suffer from mammitis between the 5th and 6th years, and that the 

 majority of attacks (nearly two-thirds) occur in the first four months 

 after parturition ; the greatest number of these soon after the act. 



The physiological activity of the milk glands in many respects 

 favours the development of inflammation. The early processes 

 of lactation, particularly the congestive stage, so closely resemble 

 acute inflammation, even in their outward manifestations, that it 

 is difficult to draw a sharp line between the two, and the inflammatory 

 non-infectious oedema noticed by Kitt is probably of this nature. 

 Both the vascularity of the gland and the processes necessary for 

 the development of secretory activity clearly favour the appearance 



