Replacement of fish meal with salicornia meal in feeds for Nile tilapia Oreochromis niloticus

We investigated the use of the halophyte salicornia Salicornia bigelovii as a replacement for fish meal in feeds containing 35% crude protein for Nile tilapia Oreochromis niloticus. Five isocaloric, isonitrogenous diets were formulated with salicornia meal to replace 0%, 20%, 40%, 60%, and 80% of the fish meal in the feed. Another diet was formulated entirely from salicornia meal. Diets were fed to three replicate groups of tilapia fingerlings (mean initial weight = 0.5 g/fish) for 6 wk in 40-L aquaria supplied with 22 C well water. Tilapia growth did not differ (P < 0.05) for fish fed diets in which 0%, 20%, or 40% of the fish meal in the diet was replaced with salicornia meal. Weight gain was reduced when fish were fed diets with higher levels of salicornia meal, and growth was slowest for fish fed diets formulated entirely from salicornia meal. Body fat was reduced and body moisture content was increased (P < 0.05) for fish fed diets in which more than 80% of the fish meal was replaced with salicornia meal. We conclude that salicornia meal can replace up to 40% of the fish meal in O. niloticus feeds without affecting growth or body composition.