BACKGROUND The present investigation was an endeavor into the elucidation of the disease-causing pathogen of streptococcosis in Nile tilapia (Oreochromis niloticus) in Egypt affecting adult fish cultured and wild fish in the Nile river. Fish were obtained from commercial fishermen, collected as part of their routine fishing activities. The researchers observed the routine fishing process and se...

The nutritional suitability and cost effectiveness of rice polish and mustard oil cake as protein sources in the diet of Nile tilapia (Oreochromis niloticus) were studied. This study introduced rice polish as a plant protein source for Nile tilapia and three diets were formulated using rice polish (0, 10 and 20%) and mustard oil cake (10.0, 17.6 and 22.0%) for a feeding trail of eight weeks to ...

Foodborne Salmonella infections have become a major problem world wide. Salmonellosis transmitted from fish are quite common. Established quality control measures exist for export oriented fish, none exists for fish consumed locally. This study aimed at characterization of Salmonella isolated from Nile tilapia . The study was carried out in selected beaches along L. Victoria in Western Kenya be...

The chemoattractant capabilities of Edwardsiella tarda extracellular products (ECP) were investigated from two isolates, the virulent FL6-60 parent and less virulent RET-04 mutant. Chemotaxis and chemokinesis were assayed in vitro using blind well chambers with peritoneal macrophages obtained from Nile tilapia, Oreochromis niloticus, 5 days following squalene injection. Non-purified ECP derived...

This study aimed to verify the sedative and anaesthetic effect of the essential oils of basil (Ocimum basilicum) (EOOB) and lemongrass (Cymbopogum flexuosus) (EOCF) in Nile tilapia juveniles. The fish were transferred to aquaria containing different concentrations of each essential oil: 10, 25, 50, 100, 200, 400 and 600 μL L-1. The time of sedation ranged from 7 to 31 seconds and the recommende...

Chlorpyrifos is an organophosphorous insecticide widely used in agriculture and domestic activities. However, little is known about the effect of this pesticide on the immune system of fish and other alterations of its physiological system. The aims of the present study were the evaluation of the LC(50) (lethal concentration(50)) and the potential toxicity of this substance on Nile tilapia (Ore...

Owing to the demand for sustainable sex-control protocols in aquaculture, research in tilapia sex determination is gaining momentum. The mutual influence of environmental and genetic factors hampers disentangling the complex sex determination mechanism in Nile tilapia (Oreochromis niloticus). Previous linkage analyses have demonstrated quantitative trait loci for the phenotypic sex on linkage g...

The acute toxicity of Roundup, a glyphosate herbicide, to Nile tilapia, Oreochromis niloticus, was investigated with emphasis on histopathological effects. The values of 24-h, 48-h, 72-h and 96-h LC50 for young tilapia were 17.5, 17.1, 16.9 and 16.8 ppm, respectively, and those for adult tilapia were 46.9, 44.4, 40.0 and 36.8 ppm, respectively. They indicated that adult fish were more tolerant ...

This study was conducted to investigate the metabolizable Nutrient values of Tomato Pomace (TP) in Nile tilapia (Oreochromis niloticus). Ninety days (three month) old fish were divided into 2 groups, each group consists from 12 aquariums, and each aquarium contains 12 Nile tilapia fingerlings whereas the excreta could be collected. Fish in each group were randomly fed basal diet or basal diet m...

To investigate the potential of extensive net cage culture for Nile tilapia (Oreochromis niloticus) fingerlings, an experiment was conducted in net cages suspended in a fertilized pond. Mixed-sex population of Nile tilapia with an average initial body weight of 0.065 g was used to stock in experimental cages. Four treatments; non added-substrate without supplemental feeding (NSNF), non added-su...