On-Farm Assessment of Different Fingerling Sizes of Nile Tilapia (Oreochromis niloticus) on Growth Performance, Survival and Yield

Abstract

Rapidly increasing hatchery-raised Nile tilapia (Oreochromis niloticus) in most developing countries lack informed recommended fingerling weight for stocking in semi-intensive grow-out ponds. The current study assessed the growth performance, survival and productivity of all-male Nile tilapia fingerlings of 0.2 g, 1 g, and 5 g in an on‐farm experiment. The final mean weight of fingerlings stocked at size 5 g was significantly higher (113.80±4.21 g) (P<0.05) compared to the 0.2 g (36.99±1.14 g) and 1g (91.93±5.59 g) fingerling sizes. The mean daily weight gain was highest in 5 g stocked fingerlings (0.91±0.04 g day -1) resulting in significant differences in the final mean weight. The coefficient of correlation between fish body length and weight was high and positive ranging (R=0.95-0.98). Significantly low percent survival was recorded in 0.2 g stocked fingerlings (64.4 3±1.93%). The net annual fish yield (NAY) and profit index (PI) were significantly lower at the 0.2 g. The highest NAY and PI were recorded in the 5 g stocked fingerlings (8.59±0.09 tons ha-1 year-1 and 6.6±2.08), respectively. Thus, with appropriate Nile tilapia fingerling weight at stocking, fish farmers can maximize fish growth, yield and profits.