Gonadal State and Condition Factor of Oreochromis Niloticus (Linnaeus 1758)in a Hypereutrophic Lake

Melatonin Induced Changes in Specific Growth Rate, Gonadal Maturity, Lipid and Protein Production in Nile Tilapia Oreochromis niloticus (Linnaeus 1758)

We have investigated the effect of melatonin (MLT) on specific growth rate (SGR% day(-1)), condition factor (k), gonado-somatic-index (GSI), histological structures of gonads, serum as well as gonadal protein and lipid in Nile tilapia Oreochromis niloticus. MLT treatment in the dose of 25 μg/L for three weeks reduced SGR% day(-1) (0.9±0.04) as compared to control (1.23±0.026). The GSI value was...

Effects of triploidy induction on growth and masculinization of red tilapia [Oreochromis mossambicus (Peters, 1852)×Oreochromis niloticus (Linnaeus, 1758)]

The dynamics of a fisheries model with feeding patterns and harvesting: Lates niloticus and Oreochromis niloticus in Lake Victoria

About 14, 000 years ago, Lake Victoria contained 500 species. Of these original species, 200 have become extinct and 200 are on the endangered species list (DuHamel, 2004). Predation coupled with poor harvesting methods has caused a big economic loss on most Ugandan lakes in particular and the world at large. In this study, we formulate a model based on a standard Lotka-Volterra prey-predator m...

Proximate composition of selected potential feedstuffs for Nile tilapia (Oreochromis niloticus Linnaeus) production in Kenya

Nutrition is vital in fish farming because feed costs represent 40–50 % of the total variable production costs (SHANG, 1992; CRAIG and HELFRICH, 2002). For several decades, fishmeal has been used as the main source of protein in fish feeds (TACON and JACKSON, 1985; TACON, 1993; EL-SAIDY and GABER, 2004; ALCESTE and JORY, 2000). However, the periodically occurring low availability, competition a...

Risk estimates for children and pregnant women exposed to mercury-contaminated Oreochromis niloticus and Lates niloticus in Lake Albert Uganda

Exposure to mercury contaminated fish predisposes populations particularly children and pregnant women to various health hazards including neurotoxicity, reproductive abnormalities and cognitive disorders. Earlier studies in the Lake Albert community have demonstrated the presence of mercury in Nile tilapia and Nile perch. However, the risk estimates for vulnerable groups such as Children and p...