MAMMITIS OR MASTITIS. 707 



of a pregnant Bitch with collodion, and so securely that at birth the pup- 

 pies could not remove it. The corresponding glands were much dis- 

 tended with milk, but no inflammatory action was set up. 



The influence of cold and wet, and especially the former — particularly 

 when animals rest with the udder on the ground — has also been largely 

 ascribed as a cause of mammary inflammation, but probably there is 

 some exaggeration in this ; as Cows which are seldom housed suffer less, 

 perhaps, from this malady than those kept in warm cowsheds. Cold 

 winds or draughts in cowsheds have been especially alluded to as op- 

 erating powerfully in its production ; and though we are inclined to 

 think that these and lying on cold ground do not produce the disorder so 

 frequently as is imagined, yet there can be no doubt that while the udder 

 is very active, and is in a state of almost constant hyperaemia, it will be 

 more susceptible to alternations of temperature, particularly if the animal 

 is rendered delicate by high feeding and an artificial existence. 



Certain atmospherical conditions — as electrical storms — have been 

 supposed to exert some influence also ; and extensive outbreaks of 

 mammitis have certainly been observed to coincide with these disturb- 

 ances — the udder being attacked with a kind of phlegmonous erysipelas. 



Hygiene has been looked upon as aiding in the development of 

 mammitis; filthy and badly ventilated dwellings being greatly blamed as 

 tending to generate a miasma, which exerts a special influence on the 

 udder. 



Plethora has been imagined to be, if not an exciting, at least a predis- 

 posing cause, and so has hot weather. Bardy, quoted by Rainard and 

 Saint-Cyr, gives a description of an epizooty of mammitis which was said 

 to be due to the Cows consuming ranunculaceous plants, which were 

 very abundant in the fields where the animals grazed. The people in the 

 locality assured him that this always occurred when these plants were 

 most plentiful in certain years. 



Mammitis sometimes complicates or accompanies vaginitis, metritis, 

 peritonitis, etc., according to some authorities. 



There is much reason to believe that a particular form of mammitis is 

 due to a putrid or septic infection, and Franck is one of the strongest 

 supporters of this view. Indeed, he asserts that the majority of cases of 

 mammitis are of septic origin ; and he has experimentally proved the 

 correctness of his statement. For instance, he has repeatedly injected into 

 the teats of healthy Cows, pus from the udder of those affected with 

 mammitis, or fluid from putrid flesh, as well as putrid blood, and within 

 twenty-four hours an acute inflammation of the corresponding quarters 

 has been observed. This inflammation occurred with Cows whose udder 

 was in active function, as well as those which were " dry." The unin- 

 jured epithelium of the milk sinuses and vesicles are, therefore, not 

 protective of the gland like the pavement epithelium of the vagina ; for it 

 has been shown that when putrid flesh or blood-fluid was injected into 

 the uninjured vagina of Ewes and Cows, no inflammation was set up. 



One of Franck's experiments is instructive. A Cow which gave only a small quantity of 

 milk, had, on February 26, 1875, a quantity of fresh pus from the udder of another Cow 

 suffering from mammitis, and diluted with ten times its bulk of water, injected into the 

 teat of the left anterior quarter. Next day this quarter had all the appearance of being 

 affected with parenchymatous inflammation. The other three quarters were generally 

 intact. The secretion from the diseased quarter was yellow, creamy, and pus-like. It 

 only contained pus-globules in great quantity, and these wei;e studdied with micrococci : 



