Effect of hybridisation on fecundity of Oreochromis karongae (Trewavas 1941)

Abstract

Effect of hybridisation of female Oreochromis karongae and male O. shiranus on fecundity of O. karongae, was investigated at Bunda, Lilongwe, Malawi. Number of eggs, weight (mg) and diameter of individual egg (mm) and relative fecundity were assessed. The results revealed that hybridisation exhibited a significantly higher number of eggs (288.94 ± 15.8) per female compared to pure O. karongae (144.00 ± 7.23). There was no significant difference, in terms of number of eggs, between the hybrid and pure O. shiranus (298.60 ± 7.27). There was no significant difference between hybrid eggs size (27.8 ± 0.77 mg; 3.28 ± 0.12 mm, respectively for egg weight and diameter) and pure egg size of O. karongae (27.7 ± 0.03 mg; 3.00 ± 0.26 mm, respectively for egg weight and diameter). Therefore, hybridisation of female O. karongae and male O. shiranus may be used by farmers for increased production after further studies especially on hatchability and survival of eggs and fry, respectively. Keywords: Fecundity, Oreochromis karongae, Oreochromis shiranus, Egg diameter, Spawning