Growth and survival rates, puberty and fecundity in captive common barbel (Barbus barbus L.) under controlled conditions

Abstract

Growth and survival rates (specific growth rate – SGR; survival rate – S) of Barbus barbus L. were recorded in captivity during three years from the larval period (final body weight – W = 0.2 ± 0.03 g; SGR = 13.6 ± 1.1%/day and cumulative survival – S = 76.0 ± 2.5%) to the first reproductive season (W = 62.55 ± 13.5 g; SGR = 0.89 ± 0.05%/day; S = 59.3 ± 1.5%). Final body size and SGR were compared between both sexes. Females reached the significantly higher growth rate (SGR = 0.84 ± 0.01%/day) compared to males (SGR = 0.77 ± 0.01%/day). Early puberty was observed in 17 and 32 months old males and females, respectively. Multi-stripping activity was found out in both sexes during the first reproductive season. In total, 20%, 25.8%, 30.3%, 14.6% and 9% of females were stripped once, twice and three, four and five times, respectively. But all males produced sperm during the entire reproductive season. The highest and the lowest egg production was recorded in the middle (April) and at the beginning (March) of the reproductive season (2155 ± 925 vs. 1279 ± 298 eggs per stripping). The highest and the lowest sperm production was observed at the beginning (March) and at the end (May) of the reproductive season (7.9 ± 0.08 × 10<sup>9</sup> vs. 1.9 ± 0.06 × 10<sup>9</sup> per stripping).