MINERAL METABOLISM OF FARM ANIMALS                   287

problem in India. He also cites the work of Meggitt who found deficiencies of lime
in Assam and Harrison's soil survey in Madras Presidency showing regional defi-
ciencies. It is of course well known that soil deficiencies are reflected in the crops.
Matson⁷⁸ has observed the beneficial effects of patassium iodide, in cases of delayed
shedding of calf hair and Nayudu⁷⁹ considers that iodine fed to young calves im-
proves their appearance. Aiyer and Kayasth⁸⁰ have recently studied the chemical
composition of some fodders of the Central Provinces and Berar and find that these
are deficient in phosphorus and lime. The poor stunted growth of the cattle in
Chhattisgarh, may according to them, be due to phosphorus deficiency. According
to our own work here, some of the Muktesar pastures are markedly deficient in
phosphoric acid and lime. There is thus no question that pasture in many parts of
this country is deficient in nutrient minerals, but no systematic work has however
been done to determine if, by the addition of suitable salt mixtures, the nutritive
value of our pastures can be improved. Some experiments in our Institute, now in
progress, seem to indicate that the addition of bone meal to the ration of dairy
cows increases the milk yield. Since improvement in the condition of cattle is
linked with the agricultural prosperity of our country, research into the food values
of pastures and allied problems of nutrition in relation to Animal Husbandry is of
urgent necessity. Pioneer work on the digestibility of fodder, silage, etc., and food
values of different substances for growth and milk production has been done by
Warth and collaborators⁸¹ and by Lander and others⁸² and it is now necessary to
investigate the need of supplying minerals to the mineral deficient natural pastures
of India for the proper growth, fertility and productive capacity of her cattle.

The writer wishes to record his sincere thanks to F. Ware, Esq., F.R.C.V.S.,
I.V.S., Director of this Institute, for first asking him to take up the study of the
present subject and for his constant encouragement and advice. Thanks are also
due to the authorities of the Rowett Research Institute, Aberdeen, who gave every
facility for studying this problem at first hand. In preparing this article the writer
has received considerable help from the numerous experiments and publications of
this Institute.

                                            REFERENCES.

(1)  Forster, Z. Biol„ 1873, 9, 297, 369.
(2)  Compare McCollum and Simmonds, Newer Knowledge of Nutrition, 1925.
(3)  Proscher, Z. Physiol. Chem., 1897, 24, 285; 1899, 26, 487 ; Abderhalen, ibid, 1899, 27,
408 ; Konig, Chemistry of Human Food, 3rd Ed., 1889.
(4)  Bunge, Physiological and Pathological Chemistry, Eng. Trans., 1902, p. 83 ; Abderhalden, Z.
Physiol. Chem., 1899, 27, 356.