MAMMITIS. 
809 
bent, twisted, possibly even somewhat opened and not rarely 
actually wounded. 
In the quadruple udder of the cow, the posterior quarters 
being more exposed, naturally suffer most. 
The origin of the infection, as in ordinary wounds, varies 
greatly. First of all, we must recognize the presence almost uni¬ 
versally within the udder of bacteria capable under favorable 
conditions of inducing disease. 
The popular notion that milk within the udder is sterile has 
been quite thoroughly disproven, and it has been found by inves¬ 
tigators, among whom we may name Mr. A. R. Ward, Cornell 
University, that the active udder is rarely if ever wholly free 
from bacteria, the flora being extensive and including strepto¬ 
cocci, staphylococci, and bacilli of varieties only awaiting favor¬ 
able conditions to demonstrate their pathogenic power. These 
we liken to the bacteria found living upon the patient’s skin 
ready to generate inflammation upon the occurrence of an in¬ 
jury to the part. They are in fact closely allied to skin bacteria. 
Aside from this inevitable danger, the contact of the teat orifi¬ 
ces with putrescent dung and urine when the animal is recum¬ 
bent, not infrequently perhaps even the introduction of a soiled 
piece of hay or straw through the orifice into the milk cistern, 
the contact with the teat openings of decomposing retained pla¬ 
centa, the trickling down over the udder and teats of discharges 
in cases of metritis and vaginitis, or soiling the udder and teats 
with these discharges through the medium of the tail, all ac¬ 
count in a general way for the origin of the disease. The pres¬ 
ence of suppurating wounds on the skin of the teats almost 
always leads, as is well known, to severe mastitis, evidently by 
the micro-organisms finding their way to and through the teat 
opening. In the same way, cow-pox, sheep-pox, contagious 
apthae, and other eruptive affections of the teats lead commonly 
to mastitis, not perhaps through extension of the disease itself 
into the gland, but by the secondary suppurative affection lead¬ 
ing to infection through the teat orifice. 
Viewing mammitis as wound infection, all cases are in a 
