MAMMITIS. 
811 
impairment of circulation. The channel through the teat serv¬ 
ing as an exit for wound secretions, while dependent, is any¬ 
thing but free, clots occluding the passage, while higher up the 
swelling of the gland tissue closes the milk ducts. The inflamed 
part is also dependent to an injurious degree, which can not be 
materially modified by changing the posture of the patient, nor 
have we yet succeeded markedly in fostering a better circula¬ 
tion by mechanical support of the gland. 
The symptoms are ushered in usually by an abnormal con¬ 
dition of the glandular secretion, the milk may be clotted, 
watery or tenacious, odorless or foetid, white, yellow, bluish or, 
if containing blood, reddish ; in gangrene it becomes chocolate 
colored, the amount is decreased in varying degrees, in many 
cases to an almost or complete cessation, which may prove tem¬ 
porary or permanent. Microscopically it consists of clots of 
casein, decreased amounts of casein, fat and sugar, increase of 
salts, sometimes red blood cells, generally pus cells, and bac¬ 
teria in abundance and of various kinds. 
The color of the skin covering the affected gland as in 
wound infection differs, in some forms it is unchanged, in others 
there appear varying degrees of redness, according to the inten¬ 
sity of subcutaneous inflammation, and when gangrene threatens 
or becomes established, the color becomes a dark livid or black. 
Swelling may be absent throughout the attack, especially 
in a common form of so-called contagious mastitis of cows, the 
“gelber gait ” of the Germans, while the other extreme is ob¬ 
served in acute gangrenous mastitis of cows and ewes, where 
the affected parts swell rapidly and extremely, the swelling ex¬ 
tending to the surrounding parts, as the perineum, inferior ab¬ 
dominal walls and thighs; the swelling of these adjacent parts 
partaking chiefly of an cedematous character. Between these 
two extremes every degree is observed, the character varying 
from a rather yielding, cedematous swelling in acute cases, to 
firm, hard schirrhous masses seen in chronic mastitis of cows 
and the so-called botryomycosis of the udder of the mare. 
The local temperature, as revealed to the touch, is as vari- 
