View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Aquatic Commons FSN-FG 0001 SURVIVAL, GROWTH AND FEED UTILIZATION OF THE RECIPROCAL HYBRIDS OF Clarias gariepinus (BURCHELL, 1822) AND Heterobranchus bidorsalis (GEOFFROY, 1809) IN CONCRETE TANKS OWODEINDE, F.G.1, NDIMELE, P.E.1*, JENYO-ONI, A. 2 and ONYENANIA, O.B. 1 1Department of Fisheries, Faculty of Science, Lagos State University, Ojo, Lagos, Nigeria. 2 Department of Wildlife and Fisheries Management, Faculty of Agriculture and Forestry, University of Ibadan Copyright 2010, Fisheries Society of Nigeria. gariepinus and Heterobranchus, bidorsalis This paper was prepared for presentation at the 25th Annual International Conference and Exhibition in Administrative Staff College of Nigeria is recommended for commercial (ASCON), Topo-Badagry, Lagos, Nigeria, 25th – 29th October, 2010. aquacultural practices. This paper was selected for presentation by an FISON Program Committee following review of information contained in an abstract submitted by the Keywords: African catfish, survival rate, author(s). Contents of the paper, as presented, have not been reviewed by the Fisheries Society of Nigeria and are subject to correction by the author(s). growth performance, feed utilization, The material, as presented, does not necessarily reflect any position of the Fisheries Society of Nigeria, its officers, or members. Papers presented at reciprocal hybrid FISON meetings are subject to publication review by Editorial Committees of the Fisheries Society of Nigeria. Electronic reproduction, distribution, or storage of any part of this paper for commercial purposes without the written consent of the Fisheries Society of Nigeria is prohibited. Permission to Introduction reproduce in print is restricted to an abstract of not more than 300 words; illustrations may not be copied. The abstract must contain conspicuous Fish is an important and cheapest source acknowledgement of where and by whom the paper was presented. Write Librarian, Fisheries Society of Nigeria (FISON), P. O. Box 2607 Apapa, of animal protein it accounts for about Lagos. 37% of Nigeria’s total protein requirement Abstract {Federal Department of Fisheries (FDF), An experiment was conducted to determine 2002}. Fish production in Nigeria is the survival rate, fertilization rate, growth mainly from the captured sector, especially performance and feed utilization of the artisanal coastal and artisanal inland reciprocal hybrids of Clarias gariepinus fisheries. This sector contributes over 80% and Heterobranchus, bidorsalis. Two of total domestic production of about genetic crosses were made: C. 510,000 tonnes per annum (FDF, 2004). gariepinus♀ x H. bidorsalis♂ Over-exploitation of the marine fishery (clariabranchus) and H. bidorsalis♀ x C. resources has resulted in gradual depletion gariepinus♂ (heteroclarias). The of the stock. FAO (2003) reported that experiment was divided into two phases; Nigeria is one of the largest importers of artificial propagation of the fish species fish in the developing world, importing using synthetic hormone and rearing the about 600,000 metric tonnes annually. To fry for 14 days; and rearing the 14 days solve this short-fall in fish supply, Nigeria old fry for 35 days. In the first phase of the must encourage investments in experiment, survival of frys were estimated aquaculture. in each experimental unit (genetic cross) Genetic technologies have been used in while in the second phase, growth and different areas of biology to develop nutrient utilization were investigated. The species that possess desirable result revealed that the highest characteristics for culture. Bartley et al %fertilization, hatching rate and (1997) reported that the hybridization of %survival occurred in H. bidorsalis♀ x C. the African catfish (Clarias gariepinus) gariepinus♂ (heteroclarias) and the with the Thai catfish (Clarias differences were significant (p < 0.05). macrocephalus) produced offspring that Percentage weight gain and specific was preferred to the parental species growth rate were significantly (p < 0.05) because they had the desired flesh quality higher in clariabranchus than of the Thai catfish and the fast growth of heteroclarias. Based on the result of this the African catfish. Legendre et al (1992) study, reciprocal hybrids of Clarias reported that Heterobranchus species had 306 Owodeinde, F.G., Ndimele, P.E., Jenyo-Oni, A. & Onyenania, O.B. FISON EKO 2010 a growth rate twice as fast as that of The female broodstocks were induced by Clarias gariepinus while Clarias injecting Ovaprim, a synthetic hormone gariepinus survives in poorly oxygenated (Aqualife Syndel International Inc. water (Teugels, 1996). Hybridization Vancouver, B.C. Canada) at the rate of between these two clariid catfishes may 0.5ml / 1000g body weight. Ovulation produce offspring that possess a occurred -15 – 18 hrs after injection and combination of these desirable qualities. gentle pressure was applied to the anterior- The continuous growth of aquaculture is posterior direction on the abdomen of the hinged on the production of fish seeds with female brood fish ( C. gariepinus and H. high fertilization and survival rates, high bidorsalis) to strip them of eggs. The male feed conversion efficiency, and high brood fish of ( C. gariepinus and H. growth rate among other factors (Adebayo bidorsalis) were anaesthetized, sacrificed and Popoola, 2008). This kind of seed can and their testes removed. Milt was be obtained through genetic technology. collected after dissection of the testes and This study investigates the fertilization, immediately preserved in 0.9% NaCl hatching and survival rates of larvae of solution. Stripped eggs were later fertilized reciprocal hybrids of two African clariid with milt after sperm activation was catfish (Clarias gariepinus and initiated by the addition of 5ml fresh water Heterobranchus bidorsalis) and also and checked for motility by microscopic studies their growth performance and feed examination (Viveen et al, 1985). These utilization. are the two (2) crosses: (1) Clarias gariepinus♀ x Heterobranchus Materials and Methods: bidorsalis♂ (Clariabranchus) (2) Heterobranchus bidorsalis♀ x Clarias Experimental Fish: gariepinus♂ (Heteroclarias) This study was conducted in 2007. After about 1min of gentle stirring, Sexually matured brood fish (500 - 600g) fertilized eggs were rinsed in fresh water were obtained from Lagos State to remove excess milt and treated with University, Nigeria. The brood fish consist talcum powder for 15-30 minutes to inhibit of two male each of Clarias gariepinus adhesiveness of the egg jelly coat and to and Heterobranchus bidorsalis and two prevent clumping and suffocation of eggs female each of this same fish species. The during incubation. Eggs were incubated in broodstocks were selected based on their glass tank (70 x 45 x 35 cm3). The external morphological features as incubation jars was aerated continually and described by Viveen et al (1985). temperature was 27+10C. Hatching Experimental Procedure: occurred 23-26 hrs later. The larvae were The experiment was divided into two left for three days in the incubation jars to broad stages; absorb their yolk. (a) Artificial propagation of fish After yolk absorption, the post-larvae were species, using synthetic hormone fed Artemia naupli for a period of 14days. and raising the fry for 14 days. Aeration was done continually and the (b) Rearing of 14days old fry for water temperature, pH and dissolved another 35days. oxygen were 27+1oC, 6.5 and 4.5 mg/l respectively. Water was changed regularly (A) Artificial propagation to avoid mortality resulting from polluted The broodstocks used for the experiment water. were conditioned for two weeks in holding (B) Growth Experiment tanks in the hatchery of Lagos State A total of 180 14days old hybrid catfish University and were fed 40% crude protein (Heteroclarias and Clariabranchus) pelleted feed at 3% body weight twice juveniles were used. Thirty specimens of daily at 09:00 hr and 16:00 hr. each hybrid were randomly chosen and ISSN: 1117-3149 PROCEEDINGS OF FISHERIES SOCIETY OF NIGERIA (FISON) ASCON, BADAGRY 25th-29th OCTOBER 2010 FSN-FG 0001 307 Survival, Growth And Feed Utilization Of The Reciprocal Hybrids Of Clarias Gariepinus (Burchell, 1822) FISON EKO 2010 And Heterobranchus Bidorsalis (Geoffroy, 1809) In Concrete Tanks allocated to 6 circular flow-through tanks development. For calculating percentage {each experimental unit (that is genetic fertilization, a sample of about 50eggs cross) had three replicates}. Rearing from each replicate of each treatment were conditions were the same as described carefully taken on Petri dish containing above. The diameter of each tank was 2m water and counted under a microscope (40 and there was at least 50% water exchange times magnification) (Adebayo, 2006). daily. Each tank contained about 45l of The fertilization rate was then calculated fresh water. based on the total number of eggs counted. Prior to stocking, quicklime was applied to After hatching, the numbers of larvae the tank bottom at 150 g/m2 to eliminate within each experimental unit were parasites and invertebrate predators. carefully counted and the hatching rate Feeding trials: was calculated. Similarly, the survival rate The fish in each of the culture treatments was calculated at the end of the rearing was fed on commercial pelleted diet (56% period (49 days after hatching) based on crude protein) (Table 1) at 3% of their the initial number