Research Journal of Biological Sciences
ISSN: Online 1993-6087ISSN: Print 1815-8846
Abstract
This study was conducted to determine the best dissolved oxygen level and culture medium for the survival of the African catfish Clarias gariepinus fry.The experiment was carried out for a period of 8 weeks, out of which the brood stock used to produce the fry were maintained for 4 weeks on a diet of 40% crude protein. The study was carried out in four plastic bowls subjected to different treatments in the departmental laboratory. The plastic bowls were designated I, II, 8.III, IV respectively each representing a treatment with bowl I containing deionised spring water unaerated kept in the laboratory, bowl II contain sprung water without aeration kept in the laboratory, bowl III contain constantly aerated spring water also kept in the laboratory and bowl IV contain spring water without aeration kept outside the laboratory under ambient conditions to serve as the control. The acclimatized Clarias broodstock were semi-induced under hatchery management conditions to produce Clarias gariepinus fry on a weekly basis for 4 weeks (as when required for experiment). Each experimental treatment bowl contain 100 Clarias gariepinus fry. The experimental treatment replicates was carried out for four weeks. The mean dissolved oxygen levels and survival rates of swim up fry values obtained for the 4 weeks are:- Oxygen levels 6.57, 7.04, 7.29 and 7.06 mg L-1 for treatments I, II, III and IV, respectively, survival rates were 84.80, 95.30, 100.00 and 96.80%, respectively for each experimental treatment. Analysis of variance shows that there is significant difference in the mean survival rate values of p<0.05 level of significance. Despite the anoxic conditions r was shown to be positively correlated (r = 0.99) for survival rate implying generally that the survival rate for Clarias gariepinus fry increases with increase in oxygen level in the water. Treatment III gave the highest percentage survival rate of 100% which coincided with a 7.29 mg L -1 oxygen level and ranking second to it is the survival rate/oxygen level of treatment IV with the values 96.80%/7.06 mg L-1.
How to cite this article:
O.A. Oyelese . Fry Survival Rate under Different Anoxic Conditions in Clarias gariepinus.
DOI: https://doi.org/10.36478/rjbsci.2006.88.92
URL: https://www.makhillpublications.co/view-article/1815-8846/rjbsci.2006.88.92