Alternative dietary protein sources for farmed tilapia, Oreochromis spp.

Tilapia are widely cultured in the tropical and subtropical regions of the world and constitute the third largest group of farmed finfish, only after carps and salmonids, with an annual growth rate of about 11.5%. Global production of farmed tilapia has increased more than three-fold since 1984, from 186,544 m.t. to 659,000 m.t., representing about 4.48% of total farmed finfish in 1995, with a value of US$925 million. Feeding represents over 50% of the operational costs of aquaculture. The shortage in world production of fish meal (the main conventional protein source), coupled with increased demand for fish meal in feeds for livestock and poultry is likely to reduce the dependence on fish meal as a single protein source in aquafeeds. Therefore, fish nutritionists have made several attempts to partially or totally replace fish meal with less expensive, locally available protein sources. The present review presents alternative dietary protein sources for tilapia, with emphasis on fishery by-products, terrestrial animal by-products, oilseed plants, aquatic plants, single cell proteins, grain legumes, plant protein concentrates and cereal by-products. The nutritive values, inclusion levels, constraints and economic evaluation of these sources are discussed. (C) 1999 Elsevier Science B.V. All rights reserved.