TREE LEAVES AS CATTLE FODDER
II. DIGESTIBILITY COEFFICIENT AND NUTRITIVE VALUE OF SOME TREE LEAVES
By CHET RAM and S. C. RAY, Animal Nutrition Section, Imperial Veterinary Research Institute,
Izatnagar
(Received for publication on 12 December 1942)
IN published literature there are but few re-
ferences to the feeding value of leafy fodders from
trees. This is perhaps due to the fact that tree
leaves are little used in European countries for
feeding cattle. Morrison [1937], however, men-
tions that in some parts of the U. S. A., where
cultivation is sparse, leaves of some trees, such as
ash, birch and elder form no small part of the
forage consumed by farm animals. These tree
leaves when lopped at the right time are not only
eaten by the stock with relish but are also fairly
digestible and comparable to ordinary hay in
feeding value. In India, Lander and Dharmani
[1927] conducted a feeding trial with ensiled
shisham leaves, and found that, whereas the crude
protein in this feeding stuff is fairly well digested
(51.8 per cent), the digestibilities of crude fibre
and nitrogen-free extracts are low (34.0 and 50.0
per cent respectively). Moreover, as the total
consumption of shisham silage is poor, it cannot
form by itself a maintenance ration.
In part I of this article, Momin and Ray [1942]
have reported the seasonal variation in the chemical
composition of some edible tree leaves. The data
on chemical analysis have indicated that tree
leaves are rich in nutrients and in a number of
cases their composition is superior to many of the
well known non-leguminous fodders. In order
that more definite information may be obtained
upon their actual feeding value, digestibility trials
have been carried out with the following three
kinds of tree leaves :—
Paker (Ficus infectoria).
Wild beri (Zizyphus jujuba).
Pipal (Ficus religiosa).
In the present communication, the results of
the digestibility trials are presented.
The samples of the leaves used were collected
during the dry, summer months of May and June.
At this period of the year, as has been shown in
part I of this article, the composition of beri leaves
shows a lower value for crude protein. The crude
protein value is also comparatively low for paker
and pipal, but the ficus variety of leaves is better
provided both with crude protein and total carbo-
hydrates than those of the beri tree.
EXPERIMENTAL
For the purpose of conducting this series of
digestibility trials, two heifers (H. 45 and H. 48)
of about 4 years of age and weighing 708 and 756
lb. respectively were used. In the trial with
paker leaves, H. 51 was used in place of H. 45.
The body weight of H. 51 was 627 lbs. at the time
of the experiment, and this animal was of the same
age as the other two. In deciding the final feed-
ing plan, the writers were guided by the following
considerations.
The animals were given a fixed allowance of
2 lb. of wheat bran, (a) to ensure a partial supply
of the digestible protein and (b) to ameliorate any
possible phosphorus deficiency arising out of the
heavy ingestion of tree leaves which were found
to be excessively rich in calcium and relatively
poor in phosphorus. For the first 7 to 10 days, in
addition to the bran (with which 1 oz. of common
salt was also mixed), the animals were fed leafy
fodders ad libitum. For the first 3 to 4 days, the
animals appeared to relish the new fodders and
consumed a fairly large quantity but gradually
the consumption dropped and eventually after
about 10 days, the animals refused to consume
more than 10 to 15 lb. of the leaves. As the
quantities of bran and the individual leafy fodders
together could not supply the requirements of dry
matter and energy, the animals had to be fed with
an extra roughage in the form of wheat bhusa.
The quantity of wheat bhusa (which was fed ad
libitum) was given in the evenings after the animals
had consumed in the day time their regulated
allowances of wheat bran and leafy fodder. When,
after a preliminary feeding period of 10 days, the
animals became adjusted to the above standard-
ized ration, twentyfour hourly collections of the
voidings and food residues were made for the next
one week.
Methods of sampling for chemical analysis were
as follows: Every day during the metabolism
experiment, the leaves were collected in the morn-
ing from the trees within the Izatnagar estate
area. Soon after they were brought to the meta-
bolism shed, the leaves and tender twigs were
separated from the stalks and coarsely chopped.
From the chopped bulk sample, the quantity to
be fed was weighed out and simultaneously a
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