Nile perch (Lates niloticus) suddenly invaded Lake Victoria between 1979 and 1987, 25 years after its introduction in the Ugandan side of the lake. Nile perch then replaced the native fish diversity and irreversibly altered the ecosystem and its role to lakeshore societies: it is now a prised export product that supports millions of livelihoods. The delay in the Nile perch boom led to a hunt fo...

Mozambique tilapia Oreochromis mossambicus were housed individually during 7 days in a continuous flow-trough respirometry system and daily exposed to one of three treatments: (1) a series of knocks on the side of the aquarium, (2) a series of photo-flashes and (3) control group. Exposure to photo-flashes did not change locomotor activity but decreased both night-time and daytime oxygen consump...

We have investigated the effect of mirror-elicited agonistic behaviour on oxygen consumption in the Mozambique tilapia, Oreochromis mossambicus (Cichlidae). Males exposed to their mirror image showed higher frequencies of both lateral display and tail-beating and escalated aggression more frequently than males exposed to a transparent glass that was used as a control for the presence of a novel...

A 24-week feeding experiment was conducted to assess whether males and females of Oreochromis niloticus exhibit differences in their hematological responses and organosomatic indices to dietary AFB1 contamination. Triplicate groups of O. niloticus (initial body weight: 24.1 ± 0.6 g) were fed with four diets (Diets 1 to 4) containing 0, 20, 200, and 2,000 μg AFB1 kg-1. A significant decrease (P ...

The reproductive strategies of Cichlids: Hemichromis fasciatus, Oreochromis niloticus, Sarotherodon galilaeus and Tilapia zillii was studied from June, 2007 to December, 2008. The variability in egg –size (i.e. diameter) were measured using the micrometer eye-piece in a binocular microscope. Fecundity was estimated by direct enumeration and related to the fish species population. The sex ratio ...

Tilapia is a very common aquaculture species in Taiwan and both the so-called freshwater tilapia (Oreochromis niloticus) and seawater tilapia (O. mossambica) are available. In order to characterize muscle tropomyosin from these tilapia and hybrid ones (O. mossambica × O. niloticus ), the biochemical properties of tropomyosin among these tilapia species were analysed. The nucleotide sequences of...

The renal response to 2 doses of gentamicin (low dose of 5 mg kg-' of body weight and high dose of 25 mg kg-' of body weight) was examined in the tilapian fish Oreochromis nilotica. Gentamicin exposure induced acute tubular necrosis that peaked in severity at 2 d following intraperitonea] injection of the high dose and at 4 to 7 d following injection of the low dose. Necrosis following high dos...

Keeping food quality among consumers is of high importance. In this study in order to maintain and improve the quality of fish meat, effect of pretreatment with polyphosphates have profound effects on the functional properties of the food products. Experiments were carried out to avoid drip during storage of Tilapia (Oreochromis niloticus)fish under modified atmosphere packaging (MAP).The resul...

Glyphosate herbicide is one the most toxic pollutants for aquatic ecosystem. Changes in serum concentrations of growth hormone (GH) and muscle protein content in O. niloticus treated with different concentrations of glyphosate herbicide under laboratory conditions were evaluated. Nile tilapia Oreochromis niloticus (mean initial weight of 57.61 ± 4.8g and initial length 14.87±1.7cm) were exposed...