138 THE INDIAN JOURNAL OF VETERINARY SCIENCE AND ANIMAL HUSBANDRY [VI, II
respect, however, the data obtained on bulls and goats may be considered to be
more reliable than those obtainable on human livers, because in the case of these
animals, the conditions are better defined, the food supply can be standardised
and the history of the individual animals is known. In this preliminary work,
however, we have not been able to standardise the feed and chose animals with
comparable nutritional history. It may be that for this reason the vitamin-A
reserve in the livers of even healthy animals has shown considerable variation.
Thus the values of vitamin reserve in healthy hill bulls lie within the range of
250 to 438 blue units in three animals (a very insufficient number; numbers 7
and 13 might be considered practically healthy) with an average of 362 units,
and in the case of healthy goats, within a range of 725 to 1,125 in five animals
with an average of 943 units. In the case of hill bulls, 10 days on a vitamin-A
deficient diet appeared to lower the reserve of this vitamin in the liver only to a
slight degree. It is, therefore, of interest to note that hardly in any case do we
find a blue value in the liver of an animal (bull or goat) suffering from a disease
closely approaching the average blue value observed in the livers of healthy animals
of the same species. This observation seems to indicate that in certain diseases
such as rinderpest in bulls and goats, there is a possibility that the vitamin-A
reserve in the livers may be depleted. Whether this is a direct effect of the disease
or due to inanition following upon the inappetence and digestive irregularities
due to the lesions caused by the disease cannot at present be stated. It may
be pointed out here that in our routine rinderpest work, the animals (bulls) actually
going through the disease are not supplied with any green pasture (maximum
period from the onset, 15 days). In the case of goats, green leaves are supplied
ad libitum, but no grain ration is given during this infection. As already observed
in the case of bulls on vitamin-A deficient ration, this withholding of green fodder
for a short period is not likely by itself to lower to any considerable degree the
vitamin reserve in the livers of bulls going through an attack of rinderpest. Ad-
vanced tuberculosis and Theileriasis in bulls also apparently lead to a diminu-
tion of the vitamin reserve. One animal, Bull 55, was drenched with B. Pyocaene¬
ous, but did not become clinically infected. Curiously enough, this animal's
liver also gave a low vitamin-A value. A histopathological examination of the
liver showed mild congestion and early cirrhosis.
In the case of rabbits only healthy animal livers have been examined to
provide comparative data. It is well-known from Mellanby's work [1934] that
avitaminosis A produces serious disorders in this species of animal.
In the case of horses, apart from the foal which might be expected to have
a low vitamin reserve, both the other animals had suffered from paralysis and
were destroyed. As far as is known, the diet supplied was of the usual type
and contained green fodder. The blue values appear to be low, but as no livers
from healthy animals were available, no comparison can be made.
The vitamin reserve of the calf liver seems also to be low.