
A STUDY OF RATIONS FED TO MILCH COWS, 95 

-and the energy required for heat and muscular work, and a 
proper feeding standard will call for sufficient digestible protein, 
fats, and carbohydrates per day to meet these needs. But just 
what these weights should be is a matter of considerable uncer- 
tainty. No hard and fast rules can be laid down. Individuality 
(differences of individual animals) prevents the strict application 
of the general principles which have been learned. Differences 
in breed, handling, classes of food, powers of digestion, and 
numerous other conditions known and unknown, tend to make 
the individual equation one of great importance. 
Twenty-five or more years ago there were suggested by Prof. 
Wolff, an eminent German chemist, certain standard rations for 
different kinds of animals fed for different purposes. His standard 
ration for a milch cow calls for 24 pounds of organic matter 
which should contain 2.5 pounds of digestible protein, .4 pounds 
of digestible fat, and 12.5 pounds of digestible carbohydrates per 
day per 1,000 pounds live weight. The potential energy of these 
digestible nutrients would be about 29,600 calories. Later ex- 
perience in Germany has inclined toward making the ration nar- 
-rower and somewhat larger. On the other hand, feeding practice 
in this country has been quite different, and even our best feeders 
generally feed a wider ration than that called for by the German 
standard. Foods rich in fats, and in starch and other carbo- 
hydrates are so cheaply and easily obtained in this country that 
our practice has been to feed them more liberally than has been 
the case in Germany. Some three or four years ago the New 
York Station made inquiries by correspondence with some of the 
best dairymen of the State as to the kinds and amounts of food 
they. were feeding milch cows. Somewhat later the Wisconsin ' 
Station made the same inquiry of dairymen of that State.. Based 
upon the replies which were received from eight dairymen in New 
York and fifteen in Wisconsin, and one study made in Connecti- 
cut by the State Station, the Wisconsin Experiment Station* 
recommended a daily ration, which “‘ may be considered a standard 
American ration for milch cows in.full flow of milk, weighing 
about 1,000 pounds,” of 25.6 pounds organic matter, containing 
2.2 pounds digestible protein, .8 of a pound digestible fat, 
13.3 pounds digestible carbohydrates. The fuel value of this 
ration is about 32,200 calories, and its nutritive ratio 1 : 6.9. 
It will be noticed that the Wisconsin Station recommends in 
* F. W. Woll, Wisconsin Experiment Station Bulletin No. 33, October, 1892, page 20. 
