Dietary lipid sources affect cold tolerance of Nile tilapia (Oreochromis niloticus)

• Published in: Journal of thermal biology Vol. 79; pp. 50 - 55
• Main Authors: Abdel-Ghany, Heba M., El-Sayed, Abdel-Fattah M., Ezzat, Altaf A., Essa, Mohamed A., Helal, Amr M.
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.01.2019; Elsevier BV
• Subjects: Acclimatization; Animal Feed - standards; Animals; Coconut oil; Cold; Cold shock; Cold Temperature; Cold tolerance; Corn Oil - metabolism; Diet; Fatty acids; Feed efficiency; Fish oils; Fish Oils - metabolism; Growth; Growth rate; Lipid metabolism; Lipids; Nile tilapia; Oil sources; Oreochromis niloticus; Tilapia; Tilapia - physiology; Water temperature; Oil sources; Nile tilapia; Growth; Cold tolerance; Fatty acids
• ISSN: 0306-4565; 1879-0992
• DOI: 10.1016/j.jtherbio.2018.11.009

This study was carried out to evaluate the effects of dietary lipid sources on growth performance, fatty acids composition and cold tolerance of Nile tilapia (Oreochromis niloticus) fingerlings (7.00 ± 0.50 g/fish). The fish were fed four isonitrogenous (28% crude protein), isocaloric (500 kcal/100 g) diets containing four lipid sources; fish oil (FO), corn oil (CO), coconut oil (COCO) or fish oil/ corn oil mixture (1:1 ratio) (oil mix). The diets were offered to the fish at a daily rate of 3% of their body weights (BW), twice a day for two months. After the feeding trial, the fish were exposed to decreasing water temperature from 25 °C until the appearance of death symptoms. The results revealed that FO-based diets (FO and oil mix) produced the best growth rates and feed efficiency, followed by corn oil diet, while COCO resulted in the lowest performance. Fish fed on CO and oil mix showed higher body unsaturated fatty acids (UFA) and lower lethal temperature than those fed on FO- or COCO-based diets. These results indicate that cold shock can modify the lipid metabolism in Nile tilapia by lowering total body saturated fatty acids and raising n-6 and n-3 UFA. This finding suggests that the inclusion of high levels of plant oils in Nile tilapia feeds can enhance their cold tolerance. •The fish fed diets containing four lipid sources; fish oil, corn oil, coconut oil or a mixture of fish oil and corn oil.•Fish oil-based diets produced the best growth performance, followed by corn oil diet, while coconut oil resulted in the lowest performance.•Cold tolerance increased with increasing the ratio of unsaturated: saturated fatty acids in fish body.•The inclusion of high levels of plant oils in Nile tilapia feeds can enhance their cold tolerance.