50 
The presence of the follicular vaginitis in herds where 
an infection through the bull has been observed is not enough 
evidence to permit one to regard this catarrhal affection as 
the cause of the sterility. Follicular vaginitis is only cap- 
able of producing sterility when the infection extends itself 
to the metra; but a metritis can have many other causes; 
besides, the granular vaginitis is found very frequently with- 
out the animals suffering at all from sterility. 
The argument has been brought forward that the viru- 
lence of the infectious material or the immunity of the ani- 
mal may vary, and that accordingly the disease may prove 
to be very harmful in one case and comparatively innocent 
in the other. It can, however, be distinctly shown that 
infectious vaginitis and_ sterility in individual herds 
are in no relation; in other words, the infectious vaginitis 
is an extremely innocent infection, which very rarely causes 
any trouble at all. If one examines the propagation of 
infectious vaginitis in a herd where sterility is also com- 
mon, one will generally find that all individuals—cows, heif- 
ers and calves—are infected, but that only the cows have 
trouble with conception, the heifers becoming pregnant very 
promptly. This demonstrates the fact that the sterility is 
connected with a previous parturition. 
If a large number of heifers does not become pregnant 
then the bull was inferior, or one failed to note exactly the 
estrum periods in the animals. 
In the breeding herd of Traneka there was no difficulty in 
getting the heifers pregnant, despite an extensive dissemina- 
tion of the infectious vaginitis; many cows however remained 
sterile. Out of forty-nine heifers in Bjerrebygaard forty- 
eight became pregnant, and nearly all were suffering from 
infectious vaginitis. Similar conditions are found frequently. 
In Skovsbo for example 98 heifers out of 99 conceived, in 
spite of the infectious vaginitis, but in the same herd I 
treated 36 out of 70 cows on account of sterility, in one 
year. 
