This study examined the full and partial replacement
of the ®sh meal component of practical
diets with commercial poultry by-product meal
(PBM) for juvenile African cat®sh Clarias gariepinus
(Burchell 1822). Six test diet formulations were
based on a low temperature Norwegian ®sh meal
(LT94) as the reference protein source. Dietary
inclusion levels of PBM at 20%, 40%, 60%, 80%
and 100% substitution of total protein content
were compared with the ®sh meal-based control
diet (100% ®sh meal). All diets were iso-nitrogenous

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

Abstract: The study evaluated the dressing percentage, nutritional quality and mineral composition of six commercial fish species (Scads, Alepes djedaba, Emperors, Lethrinus lentjan, Kingfish, Scomberomorus commerson, Jobfish, Lutjanus malabaricus, Coral trout, Plectropomus maculates and Groupers, Epinephelus chlorostigma) from the Arabian gulf coast of Saudi Arabia.

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

Abstract. – The apparent digestibility coefficients of dry
matter (ADC DM), protein (ADCp), essential amino acids
(ADC EAA), and energy (ADCe) for Nile tilapia of a
selected range of animal and plant feed ingredients found
in Western European and North American markets were
determined. The investigation was able to provide useful
data and information as a prelude for effective diet formulation
for this fish species. A reference diet was used for
the basis of assessing hydrolyzed fish protein concentrate