648 X. VITAMINS D 



tain considerable amounts of vitamin D, the newly-hatched fish were 

 practically devoid of this vitamin, indicating that it had been consumed in 

 the course of development of the larvae. "^ This indicates that fishes start 

 life with adequate vitamin D, then exhaust the supply, only to accumulate 

 it again later. An especially large amount of the vitamin is lost by the 

 adult fish at the time of spawning. 



(b) Vitamins D in Higher Animals. In the higher animals, vitamin D 

 does not ordinarily occur in the body fat, but is usually concentrated in the 

 eggs and milk in amounts sufficient to supply that necessary for the growth 

 and development of the newborn. However, in the case of marine birds, 

 which live largely on fish, vitamin D has been found in the body fat. 



The proportion of vitamin D in milk depends upon many factors, in- 

 cluding species, season, period of lactation, and vitamin D intake. Cow's 

 milk is relatively low in vitamin D.^^^ Values recorded for this fluid 

 include 5.3 to 8.3 I.U./quart for milk from cows kept indoors, as con- 

 trasted with 17 to 26 I.U./quart for that from cows kept out-of-doors in 

 June.'^" This agrees well with the figures of Bechtel and Hoppert,^*^ 

 who cited 5 I.U./quart for winter milk and 44 I.U./quart for summer milk. 

 In a comprehensive study of the effect of season on the vitamin D content 

 of cow's milk, Henry and Kon'^- reported that, durhig the 1940-1941 

 season in Great Britain, the values for vitamin D varied from less than 

 0.1 I.U./g. fat in the samples collected from November to March to 0.55 

 I.U./g. fat in July and to a maximum figure of 0.97 I.U./g. fat in August. 



Dikshit and Ranganathan^^^ reported high values for the vitamin D 

 content of South Indian butters and ghee, i.e.. 6 to 18 I.U./g. fat in the 

 non-saponified residue of the fat, and 10 to 32 I.U./g. fat in the fat itself. 

 These values are much higher than those reported by Fixsen and Roscoe'** 

 for vitamin D in EngHsh and Danish butter, or than the highest figure 

 reported by Coward and Morgan'^^ for English butters in summer, namely 

 4 I.U./g. The high values for vitamin D in the Indian butters is attributed 

 to the strength of the sun to which the cows and fodder are exposed in 



"8 A. F. Hess, C. E. Bills, M. Weinstock, E. Honeywell, and H. Rivkin, Proc. Soc. 

 Exptl. Biol. Med., 25, 652-653 (1928). 



i'3 H. E. HoneyweU, R. A. Butcher, and C. D. Dahle, /. Nutrition, 2, 251-256 (1930). 



180 J. E. Campion, K. M. Henry, S. K. Kon, and J. Mackintosh, Biochem. J., 31, 81-88 

 (1937). 



181 A. E. Bechtel and C. A. Hoppert, /. Nutrition, 11, 537-549 (1936). 



182 K. M. Henry and S. K. Kon, Biochem. J., 36, 456-459 (1942). 



183 P. K. Dikshit and S. Ranganathan, Indian J. Med. Research, 38, 37-40 (1950). 



184 M. A. B. Fixsen and M. H. Roscoe, Nutrition Abst. & Revs., 7, 823-867 (1937- 

 1938). 



186 K. H. Coward and B. G. E. Morgan, Brit. Med. J., 1935, II, 1041-1044. 



