Reproductive traits of the yellow-mandi catfish Pime/odus maculatus Lacepede (Osteichthyes, Siluriformes) in captive breeding

Pimelodus maculatus Lacepede, 1803 is an important fish of the Sao Francisco river basin, where it is economically significant in both professional and sports fisheries. The fish, maintained in captivity, was subjected to hypophysation with crude caip pituitary extract. Approximately 70% of the females treated spawned viable eggs. The eggs were opaque, demersal, yellow and free. Egg stripping was performed at 213 hour-degrees (duration = 8.3 h) after the second dose injection, at water temperature of 25-26oC. Hatching occurred at 394 hour-degrees (duration = 16.3 h) after egg fertilization, at water temperature of 24-25oC. Egg fertilization rate was 64.8%. The relationship between absolute fecundity (AF), initial fertility (IF) and final fertility (FF) and body weight are expressed, respectively, by AF = - 331 + 181717 Wt (r2 = 0.62), IF = - 16839+ 158123 Wt (r2 = 0.65), and FF = -9874 + 100365 Wt (r2 = 0.63).