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Total catches of fish from the wild reached a plateau in the early 1990s. Capture fishery production for both food and non-food utilization has levelled off. There is need for aquaculture expansion and improved output. The aim of this study was to determine the most productive facility for production of Heterobranchus bidorsalis. H. bidorsalis is the most important species from the genus Heterobranchus. It is endemic to Africa. Seven hundred H. bidorsalis fingerlings were acclimatized for 7 days, 200 fingerlings were randomly selected and stocked in: Earthen ponds, Concrete tanks, and Plastic tanks labelled as T1, T2 and T3 respectively. Each treatment had two replicates, 100 fingerlings in each. The culture facilities were constructed to have water volume which was not significantly different. The earthen ponds, concrete and plastic tanks water volume was maintained at 2,320 litres, 2,304 litres, and 2,331 litres respectively. Fingerlings were fed with 2mm Coppens of 45% crude protein at 5% biomass. Feeding was carried out at 9:00 and 16:00 hours for 56 days. All treatments were given equal care. Final Standard Length, Final Total Length, Total Length Gain, Final weight Gain and Weight Gain recorded were: 13.04±0.57, 13.44±0.75, 32±0.96, 4.45±1.34, 30.36±1.13 and 23.34±2.4 respectively. Growth was significantly higher in T1. In concrete and plastic tanks, observed growth parameters recorded had the following values: 11.75±0.82 and 11.21±0.83, 12.31±0.85 and 11.95±0.89, 3.2±0.96 and 2.84±0.85, 22.24±2.78 and 21.24±5.84, and 14.85±1.7 and 14.99±1.02 for Final Standard Length, Final Total Length, Total Length Gain, Final Weight and Weight Gain respectively. There was no significance difference in growth between T2 and T3. The study did not discourage the use of concrete tanks and plastic tanks for H. bidorsalis culture, but considered earthen ponds as most ideal culture facility for yields optimization in H. bidorsalis. |
