49 
the bull is out of the question. If I include the animals which 
suffered from a metritis subsequent upon parturition, we 
have the following list: 
Number of herds ................... 24 
Treated animals ................... 777 
Without estrum ................... 328 
Festi cob gate a5. Snare ee useain te atts 313 
Metritis after delivery .. ......... 130 
It can be seen that more than the half of the animals 
were not bred to the bull at all, as they did not show any 
heat symptoms, and adding these to the 130 which had an 
acute metritis, we have 458 or 59%, the sterility of which 
can not be referred to the bull. Three hundred and fifteen 
cows had been bred to the bull once or several times before 
they were treated, but the existing lesions in the cervical 
canal and on the orificium could not be explained through 
an infection at the cohabitation. The only explanation is 
the infection during the delivery or shortly after. 
A small number of the cows which had only an endo- 
metritis, but no lesions on the cervix, could have been in- 
fected from the bull; but this number is so small, that it is in 
no relation to the frequency of the infections supposedly 
caused by the bull. I have therefore little doubt that the 
few cases where the transmission of an infection through 
the bull was evident have been exaggerated far beyond their 
importance. 
Kruse (Silkeborg) reports a case like that, where a bull 
had infected 70 cows, only a few of which became pregnant. 
Another case is mentioned by P. Jensen (Kvarndrup). I 
must, however, object to the statements of Kruse, and, later, 
of Nielsen (Sorring), who, on the basis of a few cases like 
these, claim that the majority of all sterility complaints are 
the result of follicular vaginitis and metritis derived from 
an infected bull. 
