Breeding Biology of Freshwater Spiny eel, Mastacembelus armatus from Indus River near Jamshoro, Sindh Pakistan

Abstract

Present investigation on breeding biology of freshwater spiny eel, Mastacembelus armatus was enumerated in relation to ova diameter, gonadosomatic index and fecundity from 85 specimens ranged between 25.0 to 57.0 cm and 28.0 to 367 g in length and weight respectively during April to August 2017. The diameter of ova was ranged from 0.55- 1.0 mm, all ova were found to be spherical and uniform in diameter; this indicated that the eggs were released in a single batch during the peak period of spawning (July). The values of gonad somatic index were ranged from 3.40-6.5 and from 5.3- 10.28 in male female respectively. The highest GSI values were noticed in the month of July in both cases. Fecundity was estimated from the twelve mature fishes ranged between 41.8-59.0 cm and 88.0-155.0 g in length and weight respectively. The ranged of fecundity of the present study was from 260-554 eggs, highest fecundity was observed 554 eggs at the length of 59.0cmand lowest 260 eggs at the length of 41.8 cm. The fecundity was plotted with various body parameters like total length, total weight and gonad weight. The significantly better relationship was observed between fecundity verses with gonad weight followed by body weight and linear relationship was found between fecundity with total length. It was concluded that fish Mastacembelus armatus spawns once in ayear duringthe month July as indicated by the highest values of both ova diameters and gonad somatic index