
moot UDY OF RATIONS FED TO MILCH COWS. 27 
instances other rations were thereupon suggested by us as being 
better than the ones that had been used. The owners gradually 
changed the food to the ration thus proposed, and after an inter- 
val of four weeks from the close of the first test, another twelve- 
days’ test was made of the same herd. A comparison was thus 
made of the yields of milk and butter-fat with the two different 
rations. 
The chief points upon which information was obtained were:— 
Number of animals in the herd.—In considering the number of 
animals, only those which came into the test were included. 
Usually these were all of the cows on the farm which were in 
milk at the time of the test. 
Breed, age and approximate weight of each cow.—The breed and 
age were obtained as accurately as possible from the owner. 
Since it was not practicable to take to the farm scales large 
enough on which to weigh the cows, the weights were estimated. 
This estimation was made in each case’by the Station representa- 
tive, and it is hoped that the errors of judgment may run more or 
less equally through all the herds examined. 
LWumber of months since last calf.—In most cases the time at 
which the cow dropped her last calf was known. 
Number of months till due to calve.—There was, of course, more 
or less uncertainty in this regard. 
Weights of milk-flow for the five days.—TVhe milk of each cow 
at each milking was weighed as soon as milked, to the nearest 
tenth of a pound, by the Station representative. 
Percentages and amounts of butter-fat in the milk,—A sample of 
the milk of each cow, at each milking, was taken for the deter- 
mination of the quantity of butter-fat. ‘The Babcock method of 
fat determination was employed. From the percentages of 
butter-fat in the milk, and the total weights of the milk, the daily 
yields of butter-fat were obtained. 
Kinds and weights of foods used.—The feeder was requested to 
use the same kinds and amounts of feeding stuffs during the test 
period as he had previously used. The quantity for each animal 
was weighed by the Station representative just before feeding. 
Any portions of the food left uneaten by the cows were carefully 
weighed, and due allowance was made for these uneaten residues 
in estimating the amounts daily eaten. During the test, usually 
4 
Mh, 
b; 
“a 
4g 
ss 
