Influence of Aeration Timings on Growth, Survival and Production of Labeo rohita (Hamilton) Fingerlings during High Density Seed Rearing

Abstract

A 60 day study was conducted to evaluate the impact of different timings of aeration during night hours between 18.00-24.00 h, 21.00-03.00 h and 24.00-06.00 h on growth, survival and production performance of rohu (Labeo rohita) fingerlings against a control with no aeration, in 50 m2 outdoor concrete tanks (10 m×5 m×1.3 m). L. rohita fry were stocked at a density of 0.5 million ha-1. Compared to control, aeration caused significant increase in survival, harvested size, specific growth rate and net biomass production while the feed conversion ratio significantly reduced. However, varied timing of the night aeration could not yield any significant difference in these yield attributes among the aerated treatments. Further, comparison of night aeration between 21.00-03.00 h and 24.00-06.00 h revealed relatively better performances of the fingerlings in the later treatment, indicating effectiveness of aerating the tanks after midnight (24.00- 06.00 h).