Reproductive physiology, growth performances, and physiological responses of Puntius sophore: effect of probiotic, biofloc and stocking densities

Abstract

In Bangladesh, the pool barb (Puntius sophore) is a significant small indigenous species. However, there is no report on the reproductive physiology and broodstock development of it. Determining various aspects of reproductive biology and looking into how different dietary regimes and stocking densities affect growth and haematological responses in captivity were the main objectives of the current study. Monthly collection of 480 specimens for reproductive biology study, and for broodstock development, 400 fish were collected from Brahmaputra River, Bangladesh. Sex ratio, size distribution, condition factor (K), fecundity, and gonadosomatic index (GSI) seasonal fluctuations were evaluated. For domestication study, fish were subjected to three different diets (control diet D1, biofloc D2 and probiotic containing diet D3) and three stocking densities (20, 25, and 30 fish per 400L) with triplicates. Both sexes experienced the highest condition factor (K) in June, whereas males and females experienced the lowest levels in February and January, respectively. GSI showed one peak in June for both the sexes. Fecundity ranged from 960 to 5680 eggs with average of 3116 ± 1410. All growth performances were considerably greater in probiotic treatment and lower stocking density (20 fish per 400L tank) than in the biofloc and control treatments, although food conversion ratio (FCR) was significantly lower in the probiotic treatment and lower density (20 fish). Except for RBC fed with different diets and WBC at varied stocking densities, there were no significant differences between the treatments; all haematological measures were within the normal range. Overall, data indicates that a probiotic supplementation (0.2% kg− 1 feed) stocked with 20 fish per tank (400 L) will be effective for broodstock development of this native fish in captivity.