276
Chemical Composition of Star Grass
TABLE V
Nitrogen balance
Output (gm.)
Animal
Hill Bull No. 1 .
Hill Bull No. 2 .
Intake
gm.
335
31.6
Faeces
gm.
15.8
14.0
Urine
gm.
10.6
10.1
Total
gm.
26.4
24.1
Balance
+ 7.1
+7.5
The average digestibility coefficient of the
important constituents of star grass hay, such as
crude protein, ether extract and total carbohy-
drates have been found to be 43.5, 56.5 and 51.5
respectively (Table IV). For a mature hay these
digestibility coefficients may be considered fairly
high. In Table VI, the composition and the
digestibility coefficients of some of the mature,
pure varieties of indigenous grass hay [Sen, 1938]
have been shown along with those of star grass
hay for comparative study. In Table VIII, the
quantity of individual digestible nutrients, total
digestible nutrients and starch equivalent per
100 lb. of dry material and the nutritive ratio of
the indigenous grass hay and those of star grass
hay have been shown.
Though the starch equivalent value of star
grass hay is slightly lower than the other grass
hays, the facts of its comparative richness in
digestible crude protein and its high palatability
seem to suggest that star grass hay, when fed alone,
can serve as a maintenance ration, especially if
the grass is harvested at a slightly younger stage
than that of the sample used in the present experi-
ment.
TABLE VI
Percentage composition and digestibility coefficient of some pure variety indigeneous and star grass hay
Name of the grass
Musel grass (Iscilima laxum) . . .
Spear grass Andropogon contortus) .
Anjan grass (Andropogon annulatus) .
Kollukattai grass (Pennisetum cenchroides)
Star grass (Cynodon plectostachyum) .
Percentage composition
3.15
2.97
4.87
6.38
5.44
0.97
0.96
0.83
0.68
0.90
84.60
87.07
84.12
83.01
82.84
Digestibility coefficient
12
Nill
35
47
44
17
36
30
23
57
55
57
59
60
52
TABLE VII
Digestible nutrients in some pure variety indigenous and star grass hay
(Per 100 lb. dry material)
Name of grass
Musel grass . . . . . .
Spear grass . . . . . .
Anjan grass . . . . . .
Kollukattai grass
.
.
.
.
.
Star grass .
.
.
.
.
.
.
Crude
protein
lb.
0.38
0.00
1.71
3.00
2.39
Ether
extract
lb.
0.16
0.34
0.25
0.61
0.51
Total
carbohy-
drate
lb.
46.53
49.62
49.63
49.81
43.08
Total
digestible
nutrients
lb.
47.27
50.38
51.90
53.17
46.62
Nutritive
ratio
lb.
123.9
..
30.3
17.7
19.5
Starch
equivalent
lb.
26.1
28.1
32.4
33.2
24.4
SUMMARY
With progressive maturity, the percentage crude
protein value of star grass suffered significant
losses, whereas after an initial fall, the ether ex-
tract value remained stationary and the total
carbohydrate value progressively increased up to
six months of age. Between the grass sample
cut at six months of age and that cut at seven
months, a significant difference in composition
was noticeable. The former was definitely super-
ior in quality to the latter.
The digestibility trial conducted with mature
star grass hay showed that the hay is very pala-
table and the digestibility coefficient of its im-
portant constituents are also fairly high. The
results of the digestibility experiments suggested
that the mature star grass hay by itself could
form a maintenance ration.
ACKNOWLEDGEMENT
The authors wish to thank Dr K. C. Sen,
Officer in-charge, Animal Nutrition Section, for
his interest in this work.
REFERENCES
Sen, B. (1942). Indian Fmg. 3, 421
Sen, K. C. (1938). Misc. Bull. No. 25, Imperial Council
of Agricultural Research, New Delhi.