122 INVESTIGATION IN MILK PRODUCTION. 
pounds of nutrients; that is, the milk solids produced did not 
depend so much on the protein content of the rations, as 
upon the total nutrients, and the character of the milk solids 
with reference to the per cent fat to solids not fat. 
Since the group of cows that received the rations differ- 
ing in protein content, differed in live weight, it may be ot 
interest to note the amount of protein they received and 
dairy products returned relatively. 
TABLE XLVI.—Giving Protein Received and Products Returned Daily per 1000 
Pounds Live Weight. . 





rn. t Toe . : Per Cent} Butter Solids 
GROUP Weight Protein Milk Bat Fat Not Fat 
I 890 2:29 31.20 4.54, 1.415 2.671 
II 909 1.85 33.99 3.80 1.280 2.811 
III 846 1.56 31.72 4.40 1.397 2.768 


The cows in Group I returned 31.20 pounds of milk, 
those in Group II 33.99 pounds and Group III 31.72 pounds, 
but since the milk yielded by Group I contained 4.54 per cent 
butter fat, that of Group II 3.8, and Group II 4.4, compar- 
ison cannot be made in yield of milk. If account is taken of 
the fat content it is found that 31.20 pounds of milk testing 
4.54 per cent fat are equivalent to 37.27 pounds testing 3.8 
per cent fat, and to 32.19 pounds testing 4.4 per cent fat 
and that Group I made the greater return. But since the 
excess of yield of Group I over II is 15 times greater thanits 
yield is over Group III the discrepancy in yield cannot be 
ascribed to a shortage of protein because Group III received 
less than Group II. In comparing the butter fat yielded by 
the three groups we find that Group I gave .235 more than 
Group II and .018 more than Group III. There was also a 
product of milk solids not fat which must be taken into 
account. It will be seen that when this product is made the 
basis, results are just reversed; that Group II vielded .14 of 
a pound more than Group I and .043 more than Group III; 
again showing that the difference in yield cannot be due to 
the difference in the protein fed. 
A better comparison can be made by reducing the nutri- 
ment consumed daily by each group to a starch or carbohy- 
drateequivalent by multiplying theether extract by 2.4—see 
