Effects of Different Types of Oils on Growth Performance, Survival and Carcass Composition of Nile Tilapia (Oreochromis niloticus)

Abstract

The study evaluated the growth performance, survival and body composition of Oreochromis niloticus fed isonitrogenous (25%) and isocaloric (186 cal/kg) diets containing different types of oils (fish oil (FO) and vegetable oils (VO) (Soybean oil (SO) and Peanut oil (PO)) at 6% level for a period of 42 days. Significant difference was observed in the body weight gain (WG), specific growth rate (SGR), feed conversion ratio (FCR) values, body protein and lipid content. The diet E containing a mixture of vegetable oils in equal proportions (1:1) produced the best results WG (413.25%), SGR (3.86) and FCR (1.37), whereas the diet B (75% FO + 25% VO) showed the poorest performance WG, FCR and SGR. The survival rate ranged from 55 to 100%, being 55% for C (50% FO+ 50%VO), 65% for A (100% FO) and 100% for B (75% FO+ 25%VO), D (25% FO+ 75%VO) and E (100%VO). The type of dietary lipid significantly affected the body composition of fish. Fish fed on diets B (75% FO+ 25%VO), C (50% FO+ 50%VO), E (100%VO) presented the highest body protein content compared to initial fish. The highest body protein content was obtained in the fish fed on diet B (75% FO+ 25%VO). There was no significant difference in the body protein content of fish fed on diet C (50% FO+ 50%VO) and E (100%VO) also between the initial fish and those fed on diet D (25% FO + 75% VO). The lowest body protein content was obtained with fish fed diet with A (100% FO). Tilapia fed diet containing 100% FO, had the highest body lipid content compared to the initial fish. The lowest body lipid contain was observed in the fish fed on B (75% FO+ 25%VO). There was no significant difference in body lipid and protein content among fish fed diet with D (25% FO+ 75%VO) and initial fish. Results of the present study suggest that diet supplemented with a mixture of vegetable oils (SO and PO) could totally replace fish oil and produce the best growth response in Oreochromis niloticus.