504 IX. CAROTENOIDS AND VITAMINS A 



several carotenoids had been administered separately to chickens, al- 

 though none of the carotenoids were present when normal diets were fed. 



Carotene was found in the liver oil of the California gull {Larus fuscus) 

 and of the black-backed sea-gull (L. marinus), but not in the fat extracted 

 from the serum of the latter. ^^* The carotenoid pigments, usually the 

 xanthophylls, are stored not only in the blood, liver, and retina, as one 

 might expect, but also in the adipose tissue, skin, feet, bill, and face, and 

 even in the plumage. They are likewise present in the yolk of the egg. 

 Vitamin A is present in the blood, liver, adipose tissue, and egg yolk. 



The classical observations on the role of the carotenoids in the coloring of 

 chick tissues are those of Palmer,-^ who recognized that the yellow fat, 

 skin, and egg yolk of white Leghorns are colored by dietary xanthophylls, 

 but contain only small amounts of carotenes. During the laying season, 

 xanthophylls are deposited in the egg j^olk instead of in the skin of the legs 

 and in the other areas. Lutein is the principal carotenol to be deposited in 

 the skin; it is esterified.^* Its occurrence in the tissues and egg yolk must 

 be considered as adventitious, since it completely disappears when the 

 birds are fed on a carotenoid-free diet.^^ In addition to lutein, various 

 other dietary xanthophylls such as capsanthin from pimiento and chili 

 peppers, and zeaxanthin from yellow corn, may be stored in the skin and egg 

 yolk.^^^~"i Astaxanthin was observed in the red wattles of the Korean 

 pheasant {Phasianus colchicus), and in the eggs of the black-headed gull 

 {Larus ridihundus) and of the European white stork {Ciconia ciconia)?^ 

 An astaxanthin-like carotenoid has also been found in fat from the carmine 

 Indian flamingo {Phoenicopterus roseus) , but it is not certain whether or not 

 it actually is astaxanthin. The pigment has been called phoenicopterin 

 or phoenicoxanthin.^'^'^ These are the only reports of the occurrence of 

 astaxanthin in the fowl in tissues other than in the retina. Guilbert and 

 Hinshaw^^^ observed storage of xanthophylls in the livers of hens and of 



5" W. L. BrowTi, Georgia Agr. Expt. Ski. Bull, 160, 3-11 (1930); Chem. Ahstr., 24, 

 5800 (1930). 



5«5 W. L. Browai, Georgia Agr. Expt. Sta. Bull., 183, 1-8 (1934); Chem. AbsL, 28, 6783 

 (1934). 



666 W. L. Brown, /. Biol. Chem., 110, 91-94 (1935). 



56'' W. L. Brown, /. Biol. Chem., 122, 655-659 (1938). 



668 V. Heiman and L. A. Wilhelm, Poultry Sci., 16, 400-403 (1937). 



669 J. S. Hughes and L. F. Pavne, Poultry Sci., 16, 135-138 (1937). 



"0 W. A. Morgan and J. G. Woodroof, Georgia Agr. Expt. Sta. Bull., 147, 210-215 

 (1927); Chem. Abst., 22, 465 (1928). 



6" H. W. Titus, J. C. Fritz, and W. R. Kauffman, Poultry Sci., 17, 38-45 (1938). 



"2 C. Manunta, Helv. Chim.. Acta, 22, 1151-1153 (1939). 



"3 H. R. Guilbert and W. R. Hinshaw, /. Nutrition, 8, 45-56 (1934). 



