FRESH WATER ANIMALS: DEPOSITS: AMPHIBIA 



Lederer, 1® in 1935, was the first to demonstrate the presence of 

 astaxanthin in a fresh water fish ; the skin of the common gold fish 

 Carassius auratus contains the esterified pigment as do the fins of 

 Esox ludus and skin of Lota lota. Somewhat earher Euler and 

 Virgin ^ ^ had found xanthophylls in the fiver of the pike, Esox 

 ludus, and the roach, Leudscus rutilus. Some specimens of the fresh 

 water perch, Percha fluviatilis, contain astaxanthin esters whilst others 

 contain neutral carotenoids. Steven, 2. 1 2 j^^s shown that the skin 

 of the wild trout Salmo trutta contains esters of both astaxanthin and 

 lutein (xanthophyll), the muscles esterified astaxanthin and free luetin 

 (xanthophyll), the liver only carotene and neutral xanthophylls. 



Rainbow trout {Salmo irideus) ova contain the same carotenoids as 

 those found in the eggs of wild trout. Quantatively, however, the two 

 species differ considerably. 



The eggs of Salmo far io probably contain astaxanthin. ^^^ 



Goodwin ^ ^ has examined three species of fresh water fish, the char, 

 Salvelinus spp., the Ceylon Bartus nigrofasdatus and the Argentine 

 Copdna guttata ; the first two contain astaxanthin esters and the third 

 probably lutein esters as the predominant pigments ; Steven ^ ^ has 

 also noted astaxanthin in the char. Astaxanthin was not present in 

 the gonads of Eliginus fiavaga^^^ which do however contain large 

 amounts of neutral xanthophylls and traces of carotenes. According 

 to Lonnberg ^ * the spermatozoa of Esox ludus contain carotenoids. No 

 astaxanthin is present in the following tropical fish : Platypoedlus 

 maculatus, Xiphophorus helleri, Oryzias latipes, Macropodus opercularisj 

 Colisia lalta, C. fasdata and Betta splendens. However, they all contain 

 lutein (xanthophyll) and the first two and the last three also contain 

 zeaxanthin and violaxanthin respectively. ^ ^ 



Steven has examined lampreys and found that ammocoete larvae of 

 Lampetra planed contain only xanthophylls with lutein the major 

 component ; similarly, spawning adults of L. fluviatilis contain only 

 xanthophylls. A difference is noted, however, in that 50 per cent, of 

 the pigments in the larvae are esterified, whilst all those of the spawning 

 adults are unesterified. The pigment accumulates in the non-expandi- 

 ble lipophores in the dermal and subdermal layers of the skin ; there 

 are only negligible amounts in the liver and other tissues. 



Quantitative Data 



Very few quantitative investigations have been carried out on fresh 

 water fish, the most important being those of Steven. His data on wild 

 trout {S. trutta) are summarised in Table 35. 



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