Effects of Dietary Protein and Lipid Levels on Growth Performances of Two African Cichlids (Pseudotropheus socolofi and Haplochromis ahli)

摘要

Effects of experimental diets with varying protein and lipid levels on weight gain (WG), specific growth rate (SGR), survival rate (SR), feed conversion rate (FCR), hepatosomatic and viscerosomatic indices (HSI and VSI) of two popular ornamental cichlid species, omnivorous (Pseudotropheus socolofi) and carnivorous (Haplochromis ahli) were studied for 56 days. Two crude proteins (38%CP and 56%CP) and two crude lipids (9%CL and 16%CL) rates were applied to four formulated diets: R₁ (38%CP:16%CL), R₂ (38%CP:9%CL), R3 (56%CP:16%CL) and R₄ (56%CP:9%CL). The SR was 100% in H. ahli while that of P. socolofi ranged from 66.6% to 93.3% in the two groups, respectively. The highest WG and SGR were seen in the H. ahli and P. socolofi groups fed with R₂ feed. The best FCR values were obtained in R₂ groups of H. ahli (1.64) and R₃ groups of P. socolofi (1.41). HSI values for H. ahli and P. socolofi were 2.73±0.29 to 3.25±0.34 and 3.30±0.19 to 4.02±0.09 respectively, while VSI values were 10.48±0.81 to 10.50±1.57 and 13.28±0.61 to 15.41±0.69, respectively. No significant differences were observed for HSI and VSI of H. ahli and P. socolofi (P>0.05). Our results suggest that R₂ (38%CP: 9% CL) is the most convenient feed for both species.