METABOLISM OF CAROTENOIDS AND VITAMINS A 557 



scy, 3.61 ; and Shorthorn, 2.90. On the basis of a fat content of 4%, these 

 milks would have the following carotenoid concentrations expressed in 

 Mg./lOO ml., respectively: 136, 184, 144, 116. Dann^^a and Semb et aZ.^^o 

 recorded similar variations in the carotenoid content of the colostra of dif- 

 ferent breeds of cattle. 



A number of workers, including Lesher and co-workers*'^ ^ in the United 

 States, Kon and Mawson*^^ ^^ Great Britain, Chanda and associates*^* in 

 Scotland, and others,*^ "*~*^* observed that the carotenoids decreased rapidly 

 as the colostrum gave way to mature milk. Thus, the carotenoid values 

 for cow's milk, obtained one month after the colostrum samples, by Gillam 

 et a/.,*^* were, in some cases, only 25% of those noted in the colostrum; 

 the milk values (expressed in mg. % of fat) were: Friesan, 0.38; Ayrshire, 

 0.18; Guernsey, 0.91; and Shorthorn, 0.28. On the basis of a fat content 

 of 4%, these figures expressed in jUg./lOO ml. milk are respectively as fol- 

 lows: 15.2, 7.2, 36.4, and 11.2. Wise and collaborators*^^ observed similar 

 differences in carotenoid content between the milks of different breeds of 

 cows. 



Similar variations may be noted in the preformed vitamin A, as well as in 

 the carotenoid, content in the milk of different breeds of cattle. Thus, the 

 results of Gillam et al.^^^ (expressed as mg. % fat), for the colostra of several 

 species were as follows: Friesan, 1.24; Ayrshire, 2.96; Guernsey, 1.13; 

 and Shorthorn, 3.51. In contrast to these values, the vitamin A content in 

 the milks was markedly reduced ; the average figures observed were as fol- 

 lows: Friesan, 0.52; Ayrshire, 0.37; Guernsey, 0.67; and Shorthorn, 0.48. 

 Luecke et aZ.*^^ report that the colostra of cows had the following vitamin 

 A content (/xg./lOO ml.) ; Jersey, 401; Holstein, 52; and beef cattle, 145. 



The carotenoid and vitamin A content of human milk exhibits similar 



8«9 W. J. Dann, Biochem. J., 27, 1998-2005 (1933). 



S'O J. Semb, C. A. Baumann, and H. Steenbock, J. Biol. Chem., 107, 697-703 (1934). 



*'' J. Lesher, J. K. Brody, H. H. Williams, and I. G. Macy, Am. J. Diseases Children, 

 70, 182-192 (1945). 



^■'^ S. K. Kon and E. H. Mawson, Human Milk, Wartime Studies of Certain Vitamins 

 and Other Constituents, Med. Research Council {Brit.), Spec. Rept. Ser., No. 269, 1-188 

 (1950). 



8" R. Chanda, E. C. Owen, and B. Cramond, Brit. J. Nutrition, 5, 228-242 (1951). 



8'* W. Neuweiler, Z. Vitaminforsch., 4, 259-271 (1935). 



8" N. van Eekelen and J. H. de Haas, Geneesk. Tijdschr. Ned.-Indie, 74, 1201-1208 

 (1934). 



876 O. Meulemans and J. H. de Haas, Indian J. Pediat., 3, 133-145 (1936). 



8" AI. Repetti, Fol. Gynaec. (Genova), 31, 337-364 (1934); Ber. ges. Physiol, u. exptl. 

 Pharmakol, 86, 242 (1935); Chem. Abst., 31, 6702 (1937). 



8^8 E. Svensson, Skand. Arch. PhijsioL, 73, 237-254 (1936). 



8" G. H. Wise, F. W. Atkeson, M. J. Caldwell, D. B. Parrish, and J. S. Hughes, /. 

 Dairy Sci., 30, 279-291 (1947). 



