Growth, Food Conversion and Survival of Fingerling Tilapia aurea Fed Differing Levels of Dietary Beef Tallow

Abstract

Tilapia aurea fingerlings offered isonitrogenous (32% protein), isocaloric (3600 kcal/kg) semipurified diets for 12 weeks grew significantly larger (P < 0.05) on a 12% beef tallow diet than on a fat-free diet. No significant growth differences were found between the above diets and others which contained 2, 4, 6, 8, 10 or 14% beef tallow. Feed conversion ratio patterns (g dry feed offered/g weight gain) were similar to those for growth. Best food conversion (1.9) occurred in fish fed 12% beef tallow, while poorest (2.8) occurred in fish fed the fat-free diet. Survival was greater than 90% in all treatments, with most losses attributable to escapement. The results of this experiment indicate that beef tallow is a poor dietary lipid source for T. aurea. The generally poor growth may have been due to the relatively low levels of polyunsaturated fatty acids available in the diets.