Study of growth performance of nucleus herd of family breeding in channel catfish (Ictalurus punctatus) and selection of parents with good trait

Abstract:

In recent years, the germplasm in channel catfish (Ictalurus punctatus) has degraded seriously. Family breeding of channel catfish was carried out. In the present study, the growth performance of different nucleus herd families was compared, and the parents with good trait were selected. The body length and body weight of 122-519 d of nucleus herd individuals as well as the survival rate of the families were measured and analyzed. The results showed that the average body weight of the family with the fastest growth rate was 3.53 times that of the family with the slowest growth rate. The AGR_W of these families ranged from 0.94 to 3.32 g/d. The multivariate analysis of variance (MANOVA) showed that there were significant differences (P<0.01) in harvest body weight and body length among the families, and the growth days of families had no significant influence on the harvest body weights and body lengths (P>0.05). The one-way AVOVA and Duncan analysis revealed that: (1) There were significant differences in harvest body weight and AGR_W among the A, B, C family groups (P<0.01) that were divided by AGR_W. The fast growth A family group included twenty families. The average body weight and AGR_W of the A group were significantly higher than the total average of the nucleus herd. （2）There were significant differences in growth characterization among the offspring of ten cross combinations（P＜0.01）. The 0397, 0497 and 0103 hybridization family had obvious growth heterosis. Their average harvest body weights were 20.95%, 19.47% and 14.42% higher than the total average of the nucleus herd respectively, and the average AGR_W were 20.66%, 19.81% and 15.74% higher than that of nucleus herd respectively. （3）There were significant differences in harvest body weight and AGR_W among offspring of different geographic population male parents（P＜0.05）. The offspring families of 04 and 97 geographic population male parents had obvious growth advantage. There were no significant differences in growth characterization among offspring of different geographic population female parents（P＞0.05）. The offspring families of 03 geographic population female parents grew faster. Finally, based on the data of the nucleus herd, the body length and weight relationship was constructed: W = 0.0281 L^2.7552 (R²=0.9903). And this showed that the family individuals were in allometric growth period.