40 STREPTOCOCCIC MASTITIS 
STREPTOCOCCIC MASTITIS 
Characterization. The term “‘streptococcic mastitis’ has been 
given to an infectious disease of the udder of cows caused by a 
streptococcus. It is characterized by hard foci in the gland. 
History. As early as 1848, Brennwold observed in Switzerland 
an enzodtic mastitis that was difficult to cure. The affection was 
called “‘gelber Galt.”” Since that time this affection has been found in 
nearly, if not, all countries. Among the more recent writers on this 
subject may be mentioned Hess and Borgeaud in Switzerland, 
Nocard and Mollereau in France, and Zschokke in Vienna. In 
America it does not appear to have been studied independently of the 
infectious form of mastitis described on page 25. The epizootic mas- 
titis occasionally reported in this country may be identical with this 
supposed distinctively specific disease. Zschokke found the strepto- 
coccus in 297 of the 444 cases of altered milk examined. 
Geographical distribution. This affection has been reported from 
nearly every country where cows are kept. 
Etiology. The organism that causes this disease was described 
by Kitt as Streptococcus agalactie, and by Guillebeau as Streptococcus 
contagiose. It enters the udder through the ducts of the teats. 
The writer has been unable to differentiate this streptococcus from 
the one he has found in cases of mastitis, and also in the milk of cows 
with healthy udders. Ward and Reed produced mastitis in a healthy 
udder with the streptococcus that they had isolated from a normal 
udder. 
The period of incubation is very short, one to three days in the pro- 
duced cases. 
Symptoms. The first symptom is the diminution in the quantity 
of milk, usually in but one-quarter of the udder. This is quickly 
followed by indurated foci in the affected glands. The part becomes 
inflamed. The discharge or secretion is thin, more or less colored, 
and contains pus cells and clumps of streptococci. The lesions 
develop slowly, and one quarter after another of the udder becomes 
involved. Later the milk secretion is liable to stop entirely. 
Morbid anatomy. The tissue changes are described as those of 
catarrhal inflammation of a mucous surface, followed by the develop- 
ment of new formed tissue and atrophy of the parenchymatous tissue. 
