10 
Absolute sterility in cows is not so common as is generally 
supposed, most likely not occurring more frequently than 
among our other domestic animals. 
Many animals which are being disposed of would cer- 
tainly become pregnant if kept longer and treated properly. 
As it is now, these cows are sold as soon as their daily 
amount of milk has sunk to a certain minimum; if they are 
very valuable breeding animals they are kept longer, and 
then generally become pregnant again. 
Temporary sterility is the form of sterility most fre- 
quently met with here. Abortion ranks next, and in many 
stables is the real cause of the irregularities. 
The question arises of what is the significance of sterility 
in its different forms, and to what extent are the persistent 
complaints of the farmer justified. 
I mentioned before that irregular periods of pregnancy 
cause a decrease in the milk production, but many: other 
causes are cooperative in causing the decrease. Comparisons 
of different cases indicate that the loss can vary between 
fifty to several hundred crowns per cow and per year, when 
herds of equal size with an equal number of abnormal cows 
are compared. 
It is a fact that the loss in milk production is the larger 
the more cases of abortion happen in the time of the year 
when the best and most abundant food is to be had which 
in Denmark is in the fall and winter. Furthermore a good 
milk cow is more steady in her productiveness than a poor 
one, who soon deteriorates after her last parturition. 
There are reports from a few herds which are quite con- 
clusive on this subject. 
In the herdbook of Fuehnen and in the herdbooks of the 
red Danish cattle are many notes which prove that the tem- 
porary sterility of a cow is generally accompanied with a 
decrease in the milk production. This decrease often 
amounts to a half or more of the produce in normal years. 
