Effect of different stocking densities on growth performance, feed utilization, and survival of Labeo angra (Hamilton) fry in aquaria

Abstract

This study was conducted to assess the effect of stocking density on the growth performance, feed utilization, and survival of Labeo angra (Hamilton) in nine glass aquaria each containing 30 l of water for 45 days. Three different stocking densities of 1, 1.5, and 2 fry l^-1 of water (T₁, T₂ and T₃, respectively) were assessed in three replicates each. L. angra fry of approximately 0.32 ± 0.10 g weight were stocked and fed with a commercial feed four times daily at a rate of 15–30% body weight. Growth performance in terms of final weight (2.53 ± 0.22 g), weight gain (2.20 ± 0.05 g), percentage of weight gain (567.68 ± 15.25%), average daily gain (4.90 ± 0.11% day^-1), and specific growth rate (4.54 ± 0.04% day^-1) showed significantly higher values in T₂ compared to the other treatments. Significantly lower feed conversion ratios and the highest protein efficiency ratio were noted in T₂ (1.5 fry l^-1) diets. Significantly higher survival was observed in T₂ compared to T₁ and T₃. However, the results indicated that T₂ (1.5 fry l^-1) had more positive influence on the enhancement of growth performance, feed utilization, and survival of L. angra fry nursing in aquaria.