EFFECT OF FEEDING REGIME AND STOCKING DENSITY ON GROWTH PERFORMANCE, FEED UTILIZATION AND BODY COMPOSITION OF OREOCHROMIS NILOTICUS
Zeinhom, M. Mohamed
Central Laboratory for Aquaculture Research, Agriculture Research Center, Ministry of Agriculture, Egypt.
Received 4/ 1/ 2012 Accepted 21/ 2/ 2012
Abstract
This work was carrie d out to evaluate two different feeding regimes, and three stocking densities on growth performance and feed utilization of
Nile tilapia (Oreochromis niloticus). 12-weeks feeding trial was conducted in 18 concrete ponds (2.5 ×4.0 × 1.0 m, each), filled with fresh water and aerators have been used on fish, with an average initial weight of 25.31±1.29g, using a 2×3 factorial experiment design. The two factors evaluated were: feeding regime (Artificial diet (AD) or it’s mixing with Agricultural compost (AD+C) and three stocking densities (10 (SD1), 20 (SD2) and 30 (SD3) fish/ m3). The results revealed that there was significant value in
final body weights (118.63g), body weight gain (92.93g), SGR (1.7 % / d), GSI (1.9 %) and K (2.8) were obtained by fish fed (AD+C) (SD1). In general, Fish fed artificial diet + agricultural compost at the three stocking densities were the best in growth performance and total yield. Also, stocking density 10 fish/ m3 showed the best growth performance at both feeding regimes, while stocking density 30 fish/m3 showed the best total yield at both feeding regimes. Fish fed (AD+C) (SD1) gave the best significant (P < 0.05) value of feed conversion (1.63); while the best significant (P < 0.05) feed intake value (128.11 and 129.48g feed) was observed in fish fed (AD) (SD3) and (AD) (SD2) respectively. Fish feeding regime (AD+C) increased dry matter, crude protein and gross energy content in carcass than (AD); however, it had adverse effect on carcass ash. Also, a decrease in the stocking density at both feeding régimes resulted in a significant increase in carcass dry matter, crude protein and gross energy content, while lipid content was not differed significantly by either feeding regime or stocking density
We can conclude that, according to total fish yield, fish feeding regime of artificial diet+agricultural compost at stoking density 30 fish/m3 is recommended for O. niloticus (25g), reared in aerated concrete pond.
Key words: Nile tilapia, feeding regime, stocking density, growth performance and feed utilization.