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200 fry of carp obtained from induced breeding by stripping were fed three times daily ad libitum with Artemia (DT1), commercial starter diet (DT2), and dried egg yolk (DT3)for 8 weeks. Each treatments were in triplicates in indoor hatchery. At the end of the experiment, the progenies mean weight gained (MWG) was highest in the treatments fed Artemia (3.490±0.015a) as compared to others with significant difference (P

Thirty-three broodstock of common carp (Cyprinus carpio) obtained from Panyam Fish Farm, plateau state Nigeria was used to evaluate the percentage hatchability of carp through induced natural spawning in outdoor Hapa net system, and induced breeding by stripping in indoor concrete Ponds. Spawning and fertilization was natural for experimental group 1. Ovaprim hormone was used to induce broodstock in experimental group 2 and 3, but unlike experimental group 3, experimental group 2 was not stripped manually, as the induced female broodstock shed her eggs naturally. At the end of the experiment, the mean number of eggs in one gram was found to be (733.33±3.53a) in treatment 3, as compared to that of experimental group 2 (702.00±3.21b) and experimental group 1 (709.33±4.91b), with a significant difference at (P

The aim of this study was to assess the effect of Mercuric chloride on the growth and haematological parameters in the freshwater catfish, Clarias gariepinus. A total of 30 fishes were used for each concentration as well as in the control. Clarias gariepinus was exposed to 0.02, 0.04, 0.06, 0.08 and 0.10 mg/l of HgCl2 for 56 days. The treatment with mercuric chloride was found to inflict a drastic reduction in the total count of RBC’s. The reduction was time dependent; as concentration of mercuric chloride increased, the RBC levels declined. Exposed fishes showed a significant decrease in WBC count when compared to the control. The morphological indices MCV, MCH and MCHC fluctuate as the test concentration increased. The chronic exposure to sublethal concentration of mercuric chloride to the studied fish showed a significant decrease in final body weight in comparison to control group. Also, Growth parameters such as specific growth rate (SGR), food conversion efficiency (FCE), protein efficiency ratio (PER), food conversion rate (FCR) decreased with increased concentration of mercuric chloride. The mercuric chloride caused a significant decrease in the survival rate (P < 0.05).

Common carp (Cyprinus carpio) germplasm were sourced from Bauchi and Ibadan aimed at studying their hatchability from the various intraspecific crosses and effect of frequencies of feeding on stocking density of Carp fry. Both male and female were injected with Ovaprim at 0.5ml/kg body weight intramuscularly at a single dose. The number of eggs in 1 gram mass was determined, Fertilization rate and percentage of hatchability were calculated. One hundred and eighty (180) fry of Cyprinus carpio were randomly picked and distributed in nine bowls of 50 litres at three stocking densities with replicates for each treatment. The frequencies of feeding were in these order; Ten (10) fry per bowl of 50 litres were fed twice a day, Twenty ( 20) fry per bowl of 50 litres were fed four times a day, Thirty (30) fry per bowl of 50 litres were fed six times a day, respectively for 8 weeks with 30gm of 0.2mm Coppens starter diet. The Ib♀ x Ba♂ cross had the highest hatchability though highest fertilization rate was recorded by Ba♀ X Ba♂ cross. The various crosses had above 50% hatchability, though percentagehatchability differed significantly at (P

This study was designed to investigate the biometric parameter of some selected fish from doma dam, Nassarawa State. Samples of Hydrocynus breves, Alestes dentex , Hydrocynus forskali , and Brycinus leuciscus were collected from landing sites and the corresponding morphometric measurement and meristic count were recorded Results reveals significant differences in twelve of thirteen morphometric parameters considered in the four fish species from the dam. The most influential morphometric variables for discrimination these species using the 1st DF were the predorsal distance, body depth, standard length and eye diameter, while anal fin ray, caudal fin ray and pelvic fin ray constituted the most influential meristic variable for discrimination of the groups. Plots of canonical discriminant functions 1 of the morphometric measurements in this study clearly showed a complete overlap between H. breves and H. foskali and a partial overlap with A. dentex but separate however from B. leuciscus . Meristic plots of canonical discriminant functions 1 however shows overlap of A. dentex , B. leuciscus and H. breves and completely separation from H. foskali .

Bioaccumulation of zinc and cadmium in body tissues of a cichlid, Oreochromis niloticus, and a mudfish, Clarias gariepinus, were investigated in three separate static experiments for eight weeks. The Clarias species accumulated zinc in the order of liver>gut>gills>whole fish>skin>muscles. The accumulation of cadmium in both species was in the order of liver>gut>gills>skin>muscle>whole fish. The Clarias species accumulated more zinc than it did cadmium. The bioconcentration factors of both species showed that of the liver to be significantly greater (p

The concentration and distribution of Cr, Cu, Pb and Zn among the tissues of a freshwater fish, Clarias gariepinus exposed to combined (composite) tannery effluent was investigated at two sublethal concentrations (2 and 6%) in static bioassay for 8 weeks. The distribution of the four metals in fish was of the order of Pb > Cr > Cu > Zn and the accumulation was found to be dose- and time-dependent. The metal levels in the liver were significantly higher (P > 0.05) than other tissues. This was followed by the gill and the gut. Relatively low accumulation of these metals was found in muscle tissue.