Evaluation of dehydrated alfalfa and salt bush (Atriplex) leaves in diets for tilapia (Oreochromis aureus L.)

The potential of dehydrated alfalfa (Medicago sativa L.) and salt bush (Atriplex numularia L.) levels in formulated diets for male tilapia was evaluated. Nine isonitrogenous diets (40% crude protein) were formulated. Fish meal protein was substituted at the rates of 5, 10, 20, and 30% with protein from dehydrated alfalfa or Atriplex leaves. A diet containing no plant leaves served as the control. Fish fed the control diet had significantly (P<0.05) better weight gain and feed conversion values. All fish fed diets supplemented with various levels of the two plant leaves demonstrated reduced growth and feed utilization efficiency (P<0.05). The growth rate and other nutritional parameters decreased with increasing inclusion levels of the two plant leaves. The adverse effects of diets supplemented with Atriplex leaves was more marked than that observed with alfalfa leaves. The use of the two plant leaves in diets for Oreochromis aureus is not recommended.