NUTRIENT REQUIREMENTS 99 
of ether extract, per one thousand pounds live weight. Cal- 
culating the food of maintenance upon this basis, and mak- 
ing allowance for the yield of milkstated in each sub-division 
in the Lehmann modification, it is found that he prescribes 
the nutrients required for the production of one pound cf 
milk, as appears in the following table. 
TABLE XIX.—Giving Lehmann Feeding Standard Factors, for the Production of 
One Pound of Milk. 



Pr A Carbo- Ether 
rotein | hydrates | Extract 
e é ‘ Lbs. bs: Lbs. 
Wihenroiving Il lbs) of milk Gailiy..-..-0.....0.s+sses.<nn0 | O81 18 018 
| 
G6 lbsmotanilke daily. se-nc-cshecesn access | .O78 18 .O18 
DMSO ferric G AiliVa> scecssne senesy oss doness O8t 5?) .018 
| 
27% Ibs. of milk daily...... Foe ee | (094 18 .025 



It is not clear why the variations given in the table 
should occur when the different quantities of milk are yield- 
ed. While Dr. Lehmann’s modification of the Wolff standard 
may be an improvement on the original, the following ques- 
tions naturally suggest themselves: 
1. Are the factors approximately correct? 
2. Are they applicable to any and all grades or qualities 
of milk yielded ? 
3. Will they answer for heifers in milk ? 
These are questions that can be determined only by ac- 
tual demonstration, for we havereached a stage in American 
agricultural research, when theoretical formule based merely 
upon calculations made in the laboratory or office carry but 
little weight. 
1. ARE THE LEHMANN FacrTors APPROXIMATELY CORRECT? 
The feeding experiment conducted at this station during 
the winter of 1894-5, in which the cows were given a fixed 
ration fora period of 154 days, during which time a full flow 
of milk and yield of butter fat was secured without gain or 
loss in body weight, throws some light on all of the points 
raised. Since it will be necessary to refer to the performance 
of the whole herd and that of some individual animals, the 
average daily nutrients consumed and milk and butter fat 
yielded by each animal and by the herd for both periods are 
given. 
