Olive waste was evaluated as a substitute ingredient for wheat bran in tilapia (Oreochromis niloticus) diets. Five experimental
diets viz., 0 (control), 25, 50, 75 and 100% olive waste (OW) replaced with wheat bran were prepared and randomly allotted to
triplicate groups with 10 fish in each group. Fish were reared in glass aquaria at a water temperature of 29 ± 10C with a
dark/light cycle of 12 h. Fish were fed at 3% of body weight twice daily for a period of 70 days. The increasing level of olive

In the present study the toxic effects of zinc (Zn) on the liver structure of Nile tilapia, Oreochromis
niloticus were investigated. Additionally, we estimated whether Zn concentration and exposure period
influence the degree and nature of histological changes in the liver of exposed fish. Two hundred and
forty fish (the average weight was 24.30± 2.85 g) were distributed randomly in twenty four glass aquaria
(80 L) with stocking density of 10 fish for each. The aquaria were divided into two groups: the first

Freshwater fish Oreochromis niloticus were exposed to sublethal concentrations of zinc for short and
long terms. Responses of hematological parameters which include red blood cells count (RBC) and
hemoglobin content (Hb) were investigated. Serum aspartate aminotransferase (AST) and alanine
aminotransferase (ALT) activities were also determined. Two hundred and forty fish (24.30 ± 2.85 g)
were distributed randomly in twenty four glass aquaria (80 L) with stocking density of 10 fish for each.

The influence of replacing diet fish meal LT94 (FM) with different levels of full fat soybean meal (FFSB) on growth
performance and enzymes activity in stomach, hepato-pancreas and intestine were investigated for Nile tilapia Oreochromis
niloticus. Four diets (D1, D2, D3 and D4) were formulated 0, 15, 20, and 20 g/100 protein of diets + DL-methionine by
replacing FFSB with fish meal respectively. Proximate composition of the diets was determined. The growth of O. niloticus