Morpho-physiological characteristics of Russian sturgeon reared in net cages

Stanimir Bonev, Lyudmila Nikolova, Georgi Georgiev

Abstract: A study was carried out on morpho-physiological characteristics of male six- and eight-summer-old Russian sturgeon (Acipenser gueldenstaedtii) reared in a net-cage farm located in a warm water dam. The fish were fed with commercial granulated sturgeon feed. It was established that the age increase resulted in: statistically significant increase of the total weight, the total carcass weight and the meat content in the carcass, the weight of the intestines, liver, heart, gills and the head without the gills; the relative share of the separate organs did not change with statistical significance, with the exception of the gills, which increase in growth was statistically significant. The differences both in morphometric and morpho-physiological characteristics were insignificant. In general, the high-backed index, the gonadosomatic index and the condition indices decrease with age; the viscero-, hepato-, spleen- and heartsomatic indices increased and the broad-backed and hardness indices practically did not change. In the younger fish, the slaughter value 1 (eviscerated weight to total weigh) and slaughter value 2 (total weight without intestines and gills to total weight) were higher at the expense of the smaller head, while the slaughter value 3 (carcass weight to total weight) of both age groups was identical. The share of the more valuable part of the fillet (the dorsal one) was also higher in the fish of younger age, although the share of the fillet to the total weight in the cleansed carcass was higher in the older individuals.

Keywords: exterior indices; morphometric measures; sturgeon

Date published: 2018-11-02