Growth Performance of the Reciprocal Hybrids of Clarias gariepinus (Burchell, 1822) and Heterobranchus bidorsalis (Valenciennes, 1840)

Abstract: An experiment was conducted to determine the survival rate, fertilization rate, growth performance and feed utilization of the reciprocal hybrids of Clarias gariepinus and Heterobranchus, bidorsalis. Two genetic crosses were made: C. gariepinus& x H. bidorsalis% (clariabranchus) and H. bidorsalis& x C. gariepinus% (heteroclarias). The experiment was divided into two phases; artificial propagation of the fish species using synthetic hormone and rearing the fry for 14 days; and rearing the 14 days old fry for 35 days. In the first phase of the experiment, survival of frys were estimated in each experimental unit (genetic cross) while in the second phase, growth and nutrient utilization were investigated. The result revealed that the highest %fertilization, hatching rate and %survival occurred in H. bidorsalis& x C. gariepinus% (heteroclarias) and the differences were significant (p<0.05). Percentage weight gain and specific growth rate were significantly (p<0.05) higher in clariabranchus than heteroclarias. Based on the result of this study, reciprocal hybrids of Clarias gariepinus and Heterobranchus, bidorsalis is recommended for commercial aquacultural practices

Consumption and physico‐chemical characteristics of smoked and smoked‐dried fish commonly produced in South Benin and contribution to recommended nutrient intakes

The work aims to assess the consumption and the physico-chemical characteristics of smoked fish and smoked-dried fish commonly produced and consumed in the South Benin. The consumption data were obtained from a survey involving 250 consumers, conducted in selected production localities of the Southern part of Benin, where 36 samples of smoked fish and smoked-dried fish were collected. The highest protein contents (dry matter) were recorded in Cypselurus cyanopterus (85.1 ± 2.3%) and Sphyraena barracuda (84.5 ± 4.2%), while the highest lipid contents were recorded in Scomber scombrus (39.0 ± 9.2%) and Ethmalosa fimbriata (22.1 ± 6.3%). Smoked and smoked-dried fish produced in South Benin contained 0.1%-12.5% (of total fatty acids) eicosapentaenoic acid and 0.1%-33.2% docosahexaenoic acid, which are the most abundant omega 3 polyunsaturated acids in these fish products. The median consumption of smoked fish (60.2 g/day) and smoked-dried fish (18.2 g/day) contributed for 112% (281.1 mg) and 72% (180.4 mg), respectively, to the adult daily recommended intake of sum of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) (250 mg/day). The daily protein intake related to the consumption of smoked fish and smoked-dried fish corresponded to 36% and 24%, respectively, of the recommended intake suggested by European Food Safety Authority (0.8 g/kg.bw/day)