Protein Sparing Effects of Lipids in The Practical Diets of Oreochromis niloticus (Nile tilapia)

Abstract

A feeding trial was conducted to establish the protein sparing effects of various lipid sources in Oreochromis niloticus fingerlings (mean weight 8.05 ±0.05g) for 8 weeks. Nine experimental diets and one commercial reference diet was used for the trial. The experimental diets comprised of three levels of lipid (L) and protein (P) designated as 15P : 25L, 10P : 30L and 5P : 35L ratios. Three lipid sources used were groundnut oil, palm oil and fish oil. The result obtained showed significant differences (P<0.05) among the lipid sources. Fish oil showed significant differences in the mean weight gain (MWG), specific growth rate (SGR), feed conversion ratio (FCR) and apparent net protein utilization (ANPU) for all the treatments. The carcass composition was also significant (p<0.05) in moisture, lipid and ash which resulted in protein sparing at 10% inclusion thereby bringing down crude protein inclusion level to 30%. groundnut oil did not show any significant difference (p>0.05) in the MWG and SGR for all the treatments but showed significant differences (p<0.05) for the FCRs, PERs and ANPUs. The palm oil based diets also gave significant difference (p<0.05) in the MWG, SGR, PER and ANPU. There was significant difference (p<0.05) in the carcass compositions. Groundnut oil was observed to spare protein at 10% inclusion level while palm oil spared same at 15% inclusion level. These findings will ensure reduction in the crude protein inclusion level in the diet of O. niloticus using these lipid sources.