Problem of sex in fish breeding and fish productivity

Abstract

The study presents materials of examinations about the influence of rations on development and reproductivity of carp females and males. Fish growing from the first year of life: the first variant albuminous fodder mixture - 33 % albumen at low-sour base of the mixture, alkali-acid relation 1,14; the second one - carbohydrate mixture - 20...23 % albumen at low-alkali base of the mixture, alkali-acid relation 0,65...0,91. Fodder methionine has been added as estimated 75 mg/g of the mass in fish body. Chemical base of rations has determined not only the weight growth, the character of substances exchange, but also the sex composition of fishes in groups. The number of albumen in the limits of 30...33 % and low acidity of the ration have stipulated raising in males groups till 56,1 %. The content of albumen in the limits 19 % at low-alkali base has increased in groups the number of females till 62,4 %. The additives of methionine into the carbohydrate ration have increased the number of females till 71 %.