STORAGE OF CAROTENOIDS AND OF VITAMINS A 499 



ratios were likewise observed in migratory fishes as, for example, the North 

 Atlantic salmon (Salmo solar), the rainbow trout {Salmo irideus), and 

 others. In no cases were the levels of liver vitamin A2 comparable in 

 amount to those of vitamin Ai found in many of the saltwater fishes. 

 For a more extended discussion of the subject of vitamin A storage in 

 fishes, as well as of that of vitamins Ai and A2 as related to species, the 

 reader is referred to The Lipids, Vol. I, pages 675 to 683. 



(6) Carotenoids and Vitamins A in Aquatic Mammals. Although one 

 might expect the presence of carotenoids in species of whales such as 

 Odontoceti (toothed whales) which subsist largely on small crustaceans 

 ("krill"), Drummond and MacWalter^^^ are of the opinion that the ca- 

 rotenoids in the food remain largely unabsorbed ; they demonstrated that 

 the feces of these mammals contained a large amount of astaxanthin. 

 On the other hand, Wagner^®" found considerable /3-carotene in the food 

 in the intestines of blue and fin whales caught near the Faroe Islands. He 

 is of the opinion that this provitamin is the source of the vitamin A in these 

 mammals (see page 486). Astaxanthin is rarely found in the body oils.'*''^ 

 In fact, Barua and Morton^^^-^^'^ state that they have never encountered 

 astaxanthin in whale liver oils. Schmidt-Nielsen et al.^^^ obtained red oils 

 from the livers of the great blue whale {Balaenoptera musculus) , but Burk- 

 hardt and co-workers^*^ consider that this occurs only under pathologic con- 

 ditions. Wagner and Vermeulen^"'' reported the absence of carotene from 

 the flesh, liver, and milk of blue, sperm, and fin-backed whales, although 

 vitamin A was present in considerable amounts, especially in the sperm 

 whale. ^^^ Morton and Rosen, cited by Goodwin, ^^^ were unable to find 

 carotenoids in whale ovaries. In the case of Risso's dolphin, or grampus 

 {Grampus griseus), which subsists on such prey as seals and smaller whales, 

 and which would therefore consume no carotenoids in the diet, the liver 

 oils are devoid of carotenoids, as would be expected. ^'^^ 



The vitamin A in the liver oils of whales is largely esterified. Kascher 

 and Baxter^^^ stated that 100% of the liver oil of Cetaceae spp. is in the 

 form of the ester, while Morton and Stubbs^^^ reported that the ester frac- 

 tion of whale liver oil based upon chromatographic separation was 88.7%, 

 while that present as the free alcohol amounted to 9.6%. 



"6 J. C'. Drummond and R. J. MacWalter, J. Expll. Biol, 12, 105-107 (1935). 



"' R. K. Barua and R. A. Morton, unpublished observations, 19-49, cited by T. W. 

 Goodwin, The Comparative Biochemistry of the Carotenoids, Chapman & Hall, London, 

 1952, p. 197. 



^38 H. M. Kascher and J. G. Baxter, Ind. Eng. Chem., Anal. Ed., 17, 499-503 (1945), 

 p. 499. 



"9 R. A. Morton and A. L. Stubbs, Biochem. J., Ifi, Iviii (194G). 



