ESTIMATION OF VITAMIN-A RESERVE IN THE LIVERS OF
                                SOME FARM ANIMALS

                                                    BY

                                         K. C. SEN, D.Sc.,

          Biochemist, Imperial Institute of Veterinary Research, Muktesar,

                                                AND

                                G. K. SHARMA, G.P.V.C.,

            Clinical Assistant, Punjab Veterinary College, Lahore.
                (Received for publication on 20th December, 1935).

                                    INTRODUCTION

A considerable amount of discussion has centred round the suggestion of
Green and Mellanby [1928] that vitamin-A increases the resistance of the animal
body to bacterial infection, and the clinical work carried out by Mellanby and
Green [1929] on the effect of vitamin-A- therapy in cases of puerperal septicaemia,
which gave apparently beneficial results, appeared to indicate that the administra-
tion of this vitamin might find a wide application in the treatment of infectious
diseases. This hope has not so far been realised. Thus Harris, Innes and Griffith
[1932] found that the infections observed in cases of vitamin-A deficiency are of
a special type limited in origin to epithelial tissues, and not seen in the absence
of neighbouring keratinization, and that the existing data afforded no basis for
the belief that vitamin-A therapy was likely to bo effective in combating acute
general infections due to specific pathogenic micro-organisms, or in those clinical
toxaemias and infectious diseases which are unassociated with the peculiar struc-
tural breakdown of epithelial tissue, and the attendant localised infec-
tion, which characterises the vitamin deficiency. The observations of Wolff
[1932] and Moore [1932] on the vitamin-A reserve of human livers in health and
disease have also shown that it is extremely difficult to correlate a low reserve of
vitamin-A in liver with any particular type of infection. The trend of Moore's
work, however, suggests that partial vitamin-A deficiency, or the state of mul-
tiple malnutrition which it must usually imply, may be of importance in the
etiology of some types of infection under the conditions usually observed in clinical
practice. It is also now realised that in many cases vitamin-A therapy may not
increase the storage of this vitamin in the liver. Thus Green [1932] found that
the vitamin-A reserves were low in most puerperal cases, and that they might
remain low even after large amounts of vitamin-A had been administered thera-
peutically. He gives reasons for believing that this is not due to lack of absorp-
tion of vitamin-A when taken by the mouth, or to significant loss through urinary

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