Artificial reproduction and fingerling production of the African catfish, Clarias gariepinus (Burchell 1822), in protected and unprotected ponds

Abstract

In order to obtain an appropriate and reliable method for the mass production of Clarias gariepinus (Burcheli) fingeriings. experiments on artificial reproduction and pond rearing were carried out in the Republic of Congo in 1987-1991. Reproduction could be Induced throughout the year using common carp pituitaries (3 mg kg'' female). The average relative fecundity of females varied between 1.3% ± 0.3 (SEM) and 14.37o ±1.3 (SEM). The average hatching percentage of the eggsvariedbetween28.4%±4.5(SEM)and59.1%± 3.7 (SEM) respectively, in the dry and rainy season.The fluctuation of the relative fecundity as well as the fluctuation of the hatching percentage follows the seasonal fluctuation in rainfall and temperature. The use of a net cage made of mosquito netting (1 m'. 0.5 mm mesh size) and the roots of water hyacinth (E. crassipes) as an egg incubator proved to be reliable. In ponds not protected against frogs an average of 5.0 ± 2.9 (SEM) fingerlings m"^ per 40 days cycle were obtained, whereas in ponds completely surrounded by a wall of aluminium roof plates (0,8 m high) the average production was 32.3 ± 3.3 (SEM) fingeriings m"-per 40 days cycle, when they are stocked with approximately 100 larvae m'. Increasing the larval stocking density or extending the rearing period did not improve the final production. The main causes of low production in unprotected ponds are competition for food resources due to the presence of phytophagous frog larvae and cannibalism among the fingeriings of Clarias gariepinus. An analysis showed that the system is labour orientated, technically reliable and economically feasible when the fingeriings can be sold for US$ 0.07 apiece.

Comparison of reproductive performance of Clarias batrachus (Linnaeus, 1758) collected from three Indian rivers

“…Stripping percentage also varied significantly (p<0.05) among the fish collected from different rivers and was highest in magur from Godavari [14.57±1.026 (P); 11.82±0.184 (O)], followed by Krishna [9.74±0.286 (P); 9.90±1.149 (O)] and Narmada [10.04±0.498 (P); 9.17±0.457 (O)]. Similar values were observed in closely related species Clarias gariepinus (De Graaf et al, 1995;Shinkafi and Ilesanmi, 2014). Since stripping process was involved in the breeding programme, PGSI is employed as an index in the present study according to Oyelese (2006) instead of GSI.…”

Induced propagation of African clariid catfish, Heterobranchus bidorsalis (Geoffrey Saint Hillarie, 1809) using synthetic and homoplastic hormones

“…The non-significant differences may be attributed to the fact that the ovarian weight is usually a negligible fraction of the somatic (body) weight. de Graaf et al (1995) reported similar finding for Clarias gariepinus breed, using artificial propagation techniques. Delince et al (1987) reported that spent ovary of C. gariepinus represented about 10-20% of its initial weight.…”

Untitled

“…gariepinus and H. bidorsalis show a seasonal gonadal maturation which is usually associated with the rainy season. The maturation processes of both species are influenced by annual changes in water temperature and photoperiodicity and the final triggering of spawning is caused by a rise in water level due to rainfall (de Graaf et al, 1995). Artificial reproduction in catfish species especially C. gariepinus and H. bidorsalis have been studied by several authors (Haniffa and Sridhar, 2002;Nwokoye et al, 2007;Akinwande et al, 2009;Ataguba et al, 2009;Owodeinde and Ndimele, 2011).…”