PRACTICAL PAPERS—ABORTION IN COWS. 
269 
the proportion of nine to two ; and that 70 per cent, of those 
moved 3 ;early are pregnant, and 17 per cent, are moved yearly. 
4th. That arrest of development is the condition immedi¬ 
ately preceding the abortion; that an excessive drain upon the 
secretion of milk during pregnancy, has a tendency to pro¬ 
duce arrest of development in the foetus from inanition ; and 
that an excess of 70 per cent, of milk is demanded from the 
cows in this district where abortions prevail. 
In submitting these views for the consideration of the 
society, it must be understood that no claim is made that 
these are all the causes that produce the abortion complained 
of, or that any one of them has by itself given rise to this 
trouble. The points desired to be shown are, that the prac¬ 
tices of breeding from stock at the very early age indicated, 
and exacting from the dam the excessive amount of milk 
O 
shown to be drawn, have each injurious influences upon the 
reproductive process, tending to produce abortions ; and that, 
acting together, they in many cases do produce this result. ' 
And if it be allowed that these practices are m.arkedly preju¬ 
dicial, then various extraneous circumstances, impracticable to 
enumerate, which, under other conditions, would have little or 
no effect, now exert an active influence to bring about the 
disease. 
To so general an extent do these practices prevail, that it 
has been found practically impossible to separate the farms in 
which they exist from those that do not; for some farmers 
breed one part of their heifers at two years old, and another 
at three years old, and the farm must thus be included in both 
classes. And the irregularities heretofore referred to, with 
regard to the appearance or disappearance of the disease in 
towns, or farms, or cows, maybe accounted for, in part, by the 
changes made in the herds between different farms. 
