Ovopel® and carp pituitary extract for induction of reproduction in Colossoma macropomum females

The aim of this study was to evaluate the efficiency of the hormonal inducers Ovopel® and carp pituitary extract (CPE) for induction of reproduction in Colossoma macropomum females. The treatments were CPE at the dose of 5.5 mg/kg divided into two applications (10%; and 90% after 12 h) and Ovopel® at doses of 0.2 and 0.4 pellet/kg body weight in a single application. Eight replicates were used in each of the three treatments, totaling 24 experimental units. The females spawned when treated with the 0.2 pellet of Ovopel® (100.0%), 0.4 pellet of Ovopel® (62.5%), and CPE (87.5%), but there were no significant differences among the treatment groups in spawning rate. When there was treatment with Ovopel® spawning occurred with greater (P < 0.05) degree-hours (average water temperature × number of hours until spawning; 0.2 pellet: 417.7; 0.4 pellet: 412.3) in relation to the CPE treatment (268.9). The total oocyte weight was similar when there was treatment with Ovopel® (0.2 pellet: 832.3 g; 0.4 pellet: 798.9 g) and CPE (688.3 g). By contrast, the production index was greater (P < 0.05) with the Ovopel® treatments (0.2 pellet: 8.8%; 0.4 pellet: 9.0%) as compared with CPE (6.7%). Fertility and hatching rates were similar among the treatment groups. Ovopel® and CPE are efficient in induction of reproduction in C. macropomum females. Of the two Ovopel® treatments assessed in this study, the dose of 0.2 pellet/kg body weight is sufficient for effective induction of reproductive processes.