May 1,1925 
867 
Size of Cow in Relation to Milk Production 
* 
(3) a fairly large element in this corre¬ 
lation is the fact that the age of the 
cow materially influences her milk pro¬ 
duction and at the same time and in 
nearly like measure causes a growth 
in the size of the body parts. On the 
other hand, if one has little or no 
age milk yield for the different classes 
of cows as indicated by body measure¬ 
ments. The size of the cows is judged 
by the size of the eight different meas¬ 
urements on the cow’s body shown in 
Table II. The heavy lines of the figure 
represent the majority of the data. All 
MILK YIELD. 
Fig. 1.—Relation of body measurements and age to the milk yield of the cow. The measurements are in 
inches, the weights in pounds, and the ages in years. Those points of doubtful significance, depending 
on less than 10 individuals, are shown in dotted lines. 
knowledge of the age of the cow and 
selects from a group the largest, for 
example, in body length or girth, one 
is quite sure of choosing the cow which 
is producing the most milk. 
These facts are brought out graphic¬ 
ally in Figure 1, which shows the aver- 
the body measurements appear to be 
related to milk yield in a linear manner. 
The relation between milk yield and 
age appears to be linear up to about 
five years, when the average milk yield 
remains constant for the other ages. 
Two peculiar results are noticeable. 
