262
Studies on Protein Metabolism, 1
TABLE V
Comparison of the results of the present experiment on N-free diet with those of certain other workers
on the urinary N excretion of cattle on low-N diets
Type of animals
Growing heifers . .
Young calf . . .
Steers .
.
.
.
Cows in milk . . .
Dry cows . . .
Steers .
.
.
.
Cows
.
.
.
.
Adult hybrid bullocks .
Adult Hariana bullocks .
Ration
Wheat straw, corn
starch, cane sugar,
calcium phosphate
and salt
Clover hay and corn
(1:5)
Oat straw, corn,
potato
flakes,
molasses,
dried
beet pulp, and salts
....
Alfalfa hay and paper
pulp (2:3)
Straw, flaked maize.
starch and linseed
oil
'N-free' ration .
'N-free' ration .
Body
weight
kg.
172
145
..
412
464
..
435
255
437
Daily
N-intake
gm.
5.7
..
..
87.0
46.5
..
25.8
0.5
0.9
Daily urinary N
Total
gm.
5.68
6.48
..
16.3
14.5
..
16.8
5.00
8.42
Per kg.
body
weight
gm.
0.033
0.045
0.047
0.038
0.031
0.046
0.038
0.020
0.019
No. of
animals
averaged
2
1
2
2
2
3
2
3
3
Author
Hart et al. (1912)
Steenbock et al. (1915)
Bull and Grindley (1919)
Honcamp et al. (1923)
Copenhagen
investigators
(1923) (of. Mitchell, 1929)
Titus (1926)
Hutchinson and Morris
(1936)
Kehar et al.
Ditto
Experimental evidence indicates that, when the
low-nitrogen ration used in this investigation is fed
for a reasonably long period, the endogenous level
of urinary nitrogen excretion is approximately
reached. In future experiments, therefore, this
diet can be used in place of the absolutely nitrogen-
free diet.
Breed characteristics do not appear to affect the
endogenous nitrogen catabolism markedly.
ACKNOWLEDGEMENTS
The authors wish to express their thanks to
Chaudhary Raghbir Singh for his assistance in the
feeding and care of the experimental animals and
to Mr V. V. S. Murty and Mr A. K. Pal for helping
in the analytical work.
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