III. Antiscorbutic vitamin C » Soluble In water. Found in small amounts only, 

 in non-germinated grains and legumes, but plentifully present in fresh vegetables, seed- 

 lings, organic frult-acids, also in liver, kidneys, brains, muscle tissue and milk. 



It is unstable with heat, alkali reaction, drying and storage. So far as is known, 

 vitamin C is of importance for older fishes, 



IV. Anti-rachitic vitamin D and anti-sterility vitamin E . Both are soluble in 

 fat. The first, under the influence of ultraviolet rays Is also produced in the cutaneous 

 fat of anlioals. Its lack will cause rachitic bone diseases. Light, for reasons given 

 above, seems therefoi^ to play an important part in breeding ponds. Vitamin D is said to 

 counteract the otherwise nonhereditafy -"generation of gills and fins. 



Of vitamin E, little is known as yet, but it can only be of importance in older fish, 

 like the "respiratory vitamin" (Atmungastoff Vitamin), formerly Included in vitamin B. 



Vitamins D and E are present in green plants, seedlings, eggs, etc. Vitamin E was 

 also detected in spleen, liver, kidneys and heart. Both are almost completely absent 

 in grains and legimibs. 



\1e must regard natural foodstvtffs as very rich in vitamins, although so far researches, 

 made by Americans, have ascertained only vitamin A contents in sea plankton. 



Natural foodstuffs are superior to any and all other foodstuffs, and the resistance of 

 carps and trouts, feeding solely on natural food is greater than the resistance of such 

 fishes which are fed artificially in additlai to their natural diet. 



The need for vitamins is one of the main reasons ithy carp food should consist of 

 natural food to the extent of at least 50 per cent. But, cmce again we wish to warn the 

 fishbreeder against overrating vitamins, and for the reascsis that even trout — even under 

 intensified feeding conditions — ^will still find some natural foodstuffs. These contain 

 all the vitamins necessary for their well-being. It is certainly erroneous to try to 

 explain everything by a lack in vitamins, 



Haempel. for instance, has claimed that the poor results from potato feeding (their 

 food quotient is 20) is due to their lack in vitamins. 



Now, Schemmert and Berg have found that potatoes contain vitamin B in sufficient 

 amounts, are rich in vitamin C and even show traces of vitamin A. On the other hand, most 

 grains (food quotient 5) do not show larger ccmtents in vitamins B and A than potatoes and 

 are entirely lacking in vitamin C. 



The previously enumerated factors play certainly a greater role in pond culture than 

 the vitamins. 



Form and General Conditions of Foodstiiffs 



On account of the peculiar, anatomical str-'cture oi their head, fish can take food only 

 in small chunks or crumbs. But, then again, the size of "chunks" is of in?)ortance. It was 

 Schlemenz (1925), who introduced the law whereby fish of the same species will grow the 

 better, the larger the single chunks, or crumbs of food. He made his researches especially 

 upon carp. 



He made his studies especially upon broodlings and found that freaks which fed upon 

 real plankton — necessitating much activity — ^were far behind in growth, compared with 

 equal aged brothers and sisters which fed upon chironomus. This has been verified in other 

 fish species. For carp breeders this is of great importance from the practical viewpoint, 

 since by purchasing of sniall, retarded stodc carp, such "stupid" freaks are mostly bought, 

 while when purchasing well grown or overgrown stock, the buyer usually acquires "Intelligent" 

 chircnanus feeders. 



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