24 BULLETIN 459, U. S. DEPARTMENT OF AGRICULTURE. 
To this we have to add sufficient grain to bring the ration up to the 
requirement. The proper amount we must ascertain by trial. We 
will take, at a venture, 4 pounds of corn meal and 2 pounds of wheat 
bran. Adding this to the ration we have: 
Total dry | Digestible | Net energy 
Kiod and amount of feed. eter protein. spare 
Pounds. Pounds. Therms. 
WarmMGlare, 10) POLNGS. <n - 22 oss 2 sek a. eee ee eee 8.17 0. 23 4.39 
(CLUES ER DU eee SE Se 2 es ga 5 sees ze s Sas ses 5. 23 - 29 2. 32 
Wanmeatiesty Gnu Socnrs = oan ee ees ane = eee See ee ee 3. 59 - 26 3. 55 
Wea MTA. 2spOUNGS 22 oe socio ee eo! Soe ee eee 1.80 . 22 1.06 
Comparing these totals with the requirement as computed, we find 
that the ration is ample as regards energy but considerably low in 
digestible protem. The rather low figure for dry matter shows that 
more feed may be added to the ration if desirable, but the total 
for net energy makes it evident that what is needed is not more feed, 
but feed of a different composition, supplymg more protein along 
with rather less energy. Gluten meal answers this requirement, and 
substituting 2 pounds of it for 2 pounds of corn meal gives a ration 
which, while still a trifle high in energy, agrees as closely as necessary 
with the computed requirements. Thus: 
Total dry | Digestible | Net-energy 
Kind and amount of feed. ratte protein. ST 
Pounds. Pounds. ok : 
Saraderce, 10 POURUS: 2.0 co o= ote eee ce. one cee oe eee eel 8.17 0. 23 4.39 
inyerliny sO DUNNGS ses sere ne ne oe See eee ee ee eee 5. 23 29 2.32 
armaneal 2 pOUNUSS ose se - pm aoc see eee ee ee eee 1.77 13 1.78 
Mireatpran: 2 Pounds! 2: 3255-07. 2 ee ee eae ee eee eee 1.80 22 1.06 
Gulriveieurenieal, oa brets ee 2s oe oo season no ags- assess 1.82 -56 1.68 
Pott oy see eee as Pe ae Ue Sa ee ne oe 18.79 1.43 11.23 
This ration corresponds with the average requirement of the whole 
herd, since it is based on its average performance. It hardly need be 
said that it should be modified to suit the requirements and capacities 
of the individual cows, the heavy milkers getting more and the lighter 
ones less. 
By proceeding in this manner, with a little patience we can usually 
get a ration corresponding as closely as is necessary to the require- 
ment, provided the feeds available admit of it. With a little experi- 
ence one very soon learns to guess pretty closely, and with some prac- 
tice the computations become very easy. An exact agreement with 
the requirement need not be sought for, smce in practice the compo- 
sition of the feeds will probably vary more or less from the average of 
the tables. i 
