B. The most important foodstuffs for carp and trout. 



For reasons of profits, the breeder of carp and tench will choose 8iii5)le and cheap 

 foodstuffs for his fish. The foodstuffs used for the large carps, exclusively fed, in the 

 aquarium in Berlin — merely kept for educational and show purposes — would be far too ex- 

 pensive for commercial fisheries. Instead of seeds, such fisheries use mostly chopped up 

 fresh fish, fresh mussels, earthworms, lettuce, etc. 



Some of the main foodstuffs for carp and tench are lupine and soya bean groats. 

 Almost equally good are rye, barley and maize. Less good are the various animals flours, 

 such 35 fish flour, meat flour, cadavre flour, blood flour, etc. Very useful, in many 

 cases are vegetable waste products of not too great a water content. Animal fresh waste 

 products are also usable. Of less value are potatoes and all waste products of high 

 water contents. The same foodstuffs can be used for the brood of carp and tench, If they 

 are fed at all. 



The chief nutriments for trout fingerlings are fresh sea fish, slaughterhouse wastes, 

 knackery wastes and horse meat. The most important nutriments for trout fingerlings is 

 spleen. Substitutes are dehydrated small fish, animal meals (dehydrated), such as fish 

 meal, meat meal, etc. Less good or too costly but usable are liver, brain, blood and 

 curds. Highly nutritious but relatively costly for use in small scale feeding and grow- 

 ing of spawners, are fresh sweet water fish, shrrnps, fresh mussels, snails, frogs, 

 cockchafer (llelolontha vulgaris), etc. As fillers diluters, and binders are in use fish 

 flour, meat flour, dehydrated shrimps, blood flour, rye flour, rice middlings, wheat 

 middlings, potatoe pulp, beechwood sawdust, poplar sawdust and of late — for reasons of 

 vitamine supply — yeast and blood yeast. 



The importance and the commercial value of the different foodstuffs were previously 

 discussed. 



C. Preparation of the food and the compounding 

 of food mixtures , 



1, Food for Carp . 



Special preparation of the food for carp is often not necessary at all. To soak 

 the foodstuffs and to chop them up is usually sufficient. For smaller fish, the breeder 

 will crush or grind up the larger seeds (lupines, beans, maize). Since middlings deteri- 

 orate by and by, only a sufficient quantity for short periods should be kept on hand. 



Two year old carp of 250 grams and over and older fish will feed upon the whole seeds. 



Rye is usually crushed and only the smaller maize kernels are given whole to the fish. 

 Investigations by Salter (over a period of many years) have proven that lupines seeds are 

 just as effective in whole as in crushed form. It has also been shown that whole seeds are 

 quickly reduced to a mush in the intestines of fish. 



Middlings is soaked in water to prevent it from drifting off upon the surface of the 

 water. It is not necessary — although often done — to soak whole seeds, since the seeds 

 will swell quickly when merely thrown into the water. In Hungaria, the soaking of maize 

 kernels is done since oldest times as a matter of course. The oily advantage of it lies 

 in the stimulation of germination and of vitamine activity, 



According to Hempel, the use of pre-germinated and afterwards crushed lupines seeds 

 makes for better food utilization and the food quotient will drop from ^ to 2.5 (Sklower, 

 lately, found the opposite to be true). 



The bitterness of lupine seeds does not react unfavorably upon the fish and has 

 therefore not to be extracted. Soya beans are always fed the same as middlings, What 

 has been said of lupine is also valid for soya bean middlings, legume seeds, grain seeds, 

 com, and oil fruits, etc. 



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