Effect of chromium chloride on the utilization of broken macaroni in Blue tilapia, Oreochromis aureus, diet [electronic resource].

Includes references.

A 5x2 factorial experiment with two replicates for each combination was conducted on blue tilapia, Oreochromis aureus (8.4±O.3 g/fish) for 12 weeks in 20 concrete tanks (3 x 1 x 1 m in diameter) to evaluate the use . of broken macaroni (BM) as a carbohydrate source at 5 levels and chromium chloride (CrCl₃) supplementation at 2 levels. Five isocaloric (approximately 453.62 gross kcal gross energy/100 g) and isonitrogenous (32% crude protein) rations containing various levels of BM. 0 (control), 25, 50, 75 and 100% with or without CrCl₃ were formulated. Fish were fed at a rate of 3 % live body weight per day for six days a week for 12 weeks. The results demonstrated that CrCl₃ had positive effects on growth performance and feed utilization compared to diets free of CrCl₃. Irrespective of CrC13 supplementation, BM showed good potential as a carbohydrate source with significant (P<0.05) positive effects on growth and feed efficiency. The interaction of CrC13 and BM level was in favor of fish fed the diet of 100% BM without CrC13and all levels of BM supplemented with CrC13 compared to fish fed other diets since growth performance and fed utilization were significantly (P<0.05) improved. Except for crude protein and ether extract percentages, other carcass composition assessments were not affected by BM levels, CrCl₃ or their interaction in the diets. The simple economical evaluation revealed that the best profit margin exhibited by fish fed the diet containing 100% BM without CrCl₃ as well as 75 or 100% BM with CrC13. Finally, the present results suggested the potentiality of using BM as a good source for carbohydrate with CrCl₃ supplementation without any adverse effect on growth or feed utilization of blue tilapia cultured in concrete tanks.

Summary in Arabic.

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