Nutritional value of twoyearling carp of different cross-breeds
One of the important fields of carp breeding work is improvement of the commercial traits of created carp breeds or cross-breed commercial crosses. The main indicator determining the value of commercial fish is edible carcass yield depending on the interior (relative weight of carcass edible parts) and the exterior (high spin, ratios of head and body girth, type of scale) indices. The paper presents the results of researches on interior indicators (body parts ratio) of twoyearlings of two-breed crosses obtained from crossing of adapted fourth generation imported breeds grown in Belarus with carp lines of Belarusian selection. The edible part of carcass size varied from 60.7 % (three prim x fresinet) to 66.7% (German X Lahvinsk scaly), averaging 64.0 % in the two-breed crosses studied. Compared with the average population yield of carcass in two-breed crosses, statistically significant advantages were determined in combinations of crossing with German carp. In this regard, quite high indicators were also observed in combinations with the Yugoslav carp, where it was used as the maternal component of crosses, and in combinations obtained from crossing the Mirror Isobelin carp with a Butterfly breed. Based on comprehensive assessment of interior indicators, a number of crosses have been determined with increased nutritional value of carcasses, among which the maximum nutritional value was shown by the cross German X three prim. The obtained data are of practical importance for creation of industrial hybrids with attractive commercial traits.