Seminal characteristics of piabanha, Brycon insignis (Steindachner, 1876), after hormonal stimulation

Abstract

In order to subsidize studies about artificial reproduction of piabanha, Brycon insignis, it was investigated the seminal characteristics after application of 3 IU/g of hCG (human Chorionic Gonadotropin). The experiment was developed during the periods of January-February/1996 and February/1997, utilizing 50 three to five years-old mature males, which were liberating semen with a minimum sperm motility of 80%. The males were maintained at Experimental Station of Hydrobiology and Aquaculture Section of Companhia Energética de São Paulo, in Paraibuna, São Paulo State. The males presented an average of 29.3 cm of length and of 229.3 of total weight and liberated a milky white semen. Sixteen hours after the application of the hormone, the seminal characteristics were examined and the values obtained, when estimated by confidence interval (95%) were: semen volume, 4.41 to 4.96 mL; sperm motility, 90.10 to 91.70%, percentage of live sperm by differential staining method, 90.47 to 91.50% and spermatic concentration, 24.43 x 10⁶/mm³ to 25.10 x 10⁶/mm³. There was no statistically significant difference between the percentage of sperm motility by microscopic examination and the percentage of live sperm obtained by differential staining method, when applied the chi-square test (p< 0.05). During the development of the experiment, the water temperature was 26°C ± 1°C.