Effect Of Dietary Supplemental Phytase On Phosphorus Bioavilability in Nile Tilapia

Abstract: A 58 days trial was conducted in the Experimental Unit of Central Laboratory for Food and Feed, Agriculture Research Center, to investigate the effect of using dietary supplemental commercial phytase (500 and 1000 units) on phosphorous bioavailability in Nile tilapia Oreochromis niloticus (average mean initial weight 12.10 ± 0.6 gm/ tank). Different percentages of fish meal protein have been replaced by soybean full fat or soybean meal (50:50 or 25:75%) for each). Another five diets containing the same percentages of replacement of fish meal with either soybean full fat or soybean meal were supplemented with dicalcium phosphate. The formulated diets were iso-nitrogenous (30% CP) and the protein energy ratio were nearly the same (87 mg/Kcal). Supplementation with dicalcium phosphate or either 500 or 1000 units. Phytase improved feed conversion ratio, specific growth rate, apparent phosphorous digestibility, phosphorous retention in the body and phosphorous concentration in both vertebral column and whole body. Diet supplemented with DCP increased phosphorous in feces and phosphorous accumulation in water, while diets supplemented with 500 or 1000 units of phytase decreased phosphorous in feces and phosphorous accumulation in water. Both diets supplemented with either DCP or phytase reduced fat deposition in fish body. The results also showed that replacing 50% of the fish meal by either soybean full fat or soybean meal were not significantly different from the diet based on fish meal as a protein source, except in phosphorous concentration in both vertebral column and whole body. In conclusion it could be recommended using diets containing 50% of their protein from either soybean full fat or soybean meal supplemented with phytase as it improved fish performance and body composition, at the same time it decreased the phosphorous load in the aquatic media.
Publication year 2001
Availability location كل من جامعة القاهرة، جامعة عين شمس، مكتبة جامعة الاسكندريه، مكتبة المركز الأقليمي للإغذية و الأعلاف
Availability number
Organization Name
Country Egypt
Author(s) from ARC
External authors (outside ARC)
    سهير أحمد عرفه جامعه القاهرة
Publication Type Master Thesis
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