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Port Harcourt, Nigeria

Uka A.,African Regonal Aquaculture Center | Sikoki F.D.,University of Port Harcourt | Edun M.O.,African Regonal Aquaculture Center
Journal of Fisheries and Aquatic Science | Year: 2012

Tilapia guineensis eggs were hatched in different salinities (17, 12, 7, 5, 2 and 0 ppt). The study was conducted in eight replicates. The aim of the investigation was to ascertain d~sparityin hatching size of Tilapia guineensis attributable to salinity. Immediately hatching was observed, body weight of five hatchlings in each replicate was individually weighed in milligram. The individual total length of the five hatchlings was also measured in millimeter. The height of the yolk sac larva was determined with micrometer screw gauge graduated in millimeter from the top of the yolk sac to the dorsal region of the larva. Data obtained were used to calculate yolk sac volume. Significant differences (p<0.01) were observed in body weight and total length of larvae hatchedin different salinities. The heaviest and longest larvae were hatched in 12 ppt saline water. The yolk sac volume of larvae hatched in lower salinities were significantly higher (p<0.01) than the yolk sac volume of larvae hatched in higher salinities. The smallest yolk sac volume was recorded in 12 ppt saline water. The findings show that salinity could be manipulated for economic production of larger seeds of Tilapiaguineensis. © 2013 Academic Journals Inc.

Uzukwu P.U.,African Regonal Aquaculture Center | Aranyo A.A.,African Regonal Aquaculture Center | Uzukwu C.O.,African Regonal Aquaculture Center
Journal of Fisheries and Aquatic Science | Year: 2012

In recent times, there has been an upsurge in the culture of tilapia in Nigeria resulting in increased demand for the fingerlings which is hardly satisfied. This is due to increasing demand for table size tilapia as food fish and under-sized tilapia in the fish meal and fish canning industries in Nigeria. Collection of Tilapia guineensis fingerlings from the wild, to augment hatchery production has been the practice and this is subject to environmental fluctuations. Multivariate regression and correlation analyses of accumulated data were used to investigate the effects of changes in water quality parameters on abundance of fingerlings of Tilapia guineensis in a brackish water habitat in Lagos. Dissolved Oxygen (DO), salinity and Secchi transparency were found to be the most dominant factors affecting the abundance of Tilapia guineensis fingerlings i n the Lagos lagoon. Peak period of abundance was closely associated with period of low salinity (0.50 to 5.60 ‰), which coincided with the period of low transparency and low DO in the rainy season. The correlation analyses of Tilapia guineensis fingerlings with the water quality parameters ylelded the following correlation coefficients (r)-0.598; (salinity); -0.644 (transparency); -0.710 (DO); -0.566; (temperature) and 0.129 (pH). The abundance of Tilapia guineensis fingerlings in the Lagoon was ultimately defined by a suitable regression equation. This result is expected to optimize the collection of fingerlings of Tilapiaguineensis from the wild and boost food fish security in Nigeria and elsewhere. © 2013 Academic Journals Inc.

Behbele D.O.,African Regonal Aquaculture Center | Ansa E.J.,African Regonal Aquaculture Center | Agokei O.E.,African Regonal Aquaculture Center | Opara J.Y.,African Regonal Aquaculture Center | And 8 more authors.
Journal of Fisheries and Aquatic Science | Year: 2012

Protein is the most important nutrient in fish diet. The protein in the ingrehents must not only be chemically available but it must also be biolopcally available for the fish to utilize it. An experiment was carried out to find out the comparative effect of imported fish meal, blood meal and local fish waste based diets on the growth and survival of juvenile tilapia (0. niloticus) in concrete tank. Four hets consisting of Nigerian Institute for Oceanography and Marine Research (NIOMR) pelleted feed (40% CP) (treatment 1 and control), fresh boiled cattle blood (30% CP) (treatment 2), fresh cattle blood (30% CP) (treatment 3) and local fish waste meal (30% CP) (treatment 4) were fed to juvenile tilapia. The average initial weight of the fish was 55.24 g. The experiment was a completely randomized design in four replicates. There was no significant difference (p<0.05) in the body weight gain, average daily weight gain and average body length between the treatments. However, the relative weight gain of treatments 1 (93.69%) and 2 (80.21%) were significantly higher (p<0.05) than treatments 3 (62.37%) and 4 (64.85%). The survival was 100% in all treatments. Treatment 2 was more cost effective at N3539.06 kg-1 fish, followed by 1 with N3667.52. Treatments 3 and 4 had the highest at N3698.20 and N3718.60 kg-1 fish. The trial showed that tilapia feed processed with fresh cattle blood performed as well as imported fish meal, boiled blood and local fish waste and in adhtion was more cost effective. © 2013 Academic Journals Inc.

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