ORIGINAL ARTICLES

                    THE PROBLEM OF VITAMIN-A DEFICIENCY IN THE
                                    DIET OF FARM ANIMALS *

                                                    BY

                                           K. C. SEN, D.Sc.

                                           Officer-in-Charge

                                                    AND

                                          P. A. SESHAN, B.A.

   Assistant, Animal Nutrition Section, Imperial Veterinary Research Institute,
                                             Izatnagar, U. P.

                         Received for publication on 25th May 1938)

                                           INTRODUCTION

THE discovery of the fact that the proper growth, health and reproduc-
tion of an animal involved other factors than a sufficiency of calories and
protein has shifted the centre of interest in nutritional studies from quantity
to quality. Among these accessory constituents of food, vitamin-A occupies
a most important place. Although this substance has now become deter-
minable by chemical and spectroscopical methods, our knowledge with regard
to the requirements of the various animals and the conditions favourable
to its proper utilization is so limited that the adequacy or inadequacy of
a diet has to be judged by clinical observations only.

The symptoms characteristic of avitaminosis-A are more or less well-
defined. It would, however, be interesting to notice some recent cases on
record. Fed on over-ripe timothy hay as sole roughage in addition to a
mixture containing yellow corn meal, linseed meal, soya bean meal and wheat
bran for about twelve months, four cows, negative to contagious abortion,
consistently failed to have normal calves [Converse and Meigs, 1931]. A
ration for pigs made up of white corn, buckwheat middlings, tankage and
minerals or white corn, oats, linseed oil meal, tankage and minerals resulted
in serious eye troubles, paralysis, respiratory trouble and convulsions [Long-
well and Weakley, Jr., 1932]. A sow on a vitamin-A deficient diet gave
birth to a litter of eleven pigs, all without eyeballs [Hale, 1933]. When the
mother had received a diet short in vitamin-A content before mating and
during the first thirty days of gestation, three litters of pigs were born with-

* Paper read before the Section of Veterinary Research of the Indian Science Congress,
held in Calcutta, January, 1938.

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