Homoplastic hypophysation of African catfish (Clarias gariepinus) using male, female and a combination of male and female hypophysis

摘要

Homoplastic hypophysation was carried out on 8 Clarias gariepinus using hypophysis from males only, females only or a combination of hypophysis from males and females, at a fish farm in Okuovu (Delta state, Nigeria). There was a significant difference (P<0.05) in ovum production between treatment and control groups. Estimated ovum production per kg body weight was 82 353, 85 000 and 59 419 for the male, female and mixed hypophysis treatments respectively; there was no significant difference betweentreatments. The mean fertilization percentages were 69.0, 77.5 and 86.04 for the male, female and mixed hypophysis treatments respectively. There was a significant difference (P<0.05) between treatments; treatment with the combination of male and femalehypophysis gave the best results; ova in the control group failed to be fertilized. The mean percentage of hatching was 51.5, 59.0 and 72.0 for male, female and the combination of male and female hypophysis treatments respectively. The differences weresignificant (P<0.05) and treatment with a combination of male and female hypophysis gave the best results. The mean number of ova hatched as a percentage of the total number of ova produced was 29 264 (35.5%), 38 866 (45.7%) and 36 809 (61.9%) for male,female and mixed hypophysis respectively. The superiority of the treatment using a combination of male and female hypophysis was attributed to synergism between male and female hypophysis.