Comparative analysis of growth performance, pharyngeal teeth and intestinal traits in F1 hybrids of female Megalobrama amblycephala × male Culter mongolicus

Abstract

Aquaculture provides approximately 78% of the fish consumed by humans in China. However, the characters of fish cultivars have different deficiencies, and degradation is serious. Less improved varieties of fish are still an important factor restricting the development of aquaculture in China. Interspecific hybridization is an effective method for producing hybrid varieties with desirable traits. In this study, diploid hybrids (BM, 2n = 48) of blunt snout bream (Megalobrama amblycephala ♀, 2n = 48, BSB) × Mongolian culter (Culter mongolicus ♂, MC, 2n = 48) were obtained by intergeneric crossing. To investigate whether these hybrids have heterobeltiosis, the growth performance, pharyngeal teeth and intestinal traits of BM hybrids were compared with those of their parents (BSB and MC). The average weight of BM hybrids (97.01 ± 27.52 g) was significantly greater (P < 0.05) than that of MC (68.04 ± 12.64 g) and similar to that of BSB (99.33 ± 16.72 g) at 1 year of age; the average weight of BM hybrids (990.49 ± 149.21 g) was significantly greater (P < 0.05) than that of both BSB (895.12 ± 135.38 g) and MC (625.81 ± 81.83 g) at 2 years of age. The pharyngeal tooth structure and intestinal traits of BM hybrids were similar to those of BSB, indicating that BM hybrids were biased toward herbivory. This is the first report of a diploid hybrid with a growth advantage and herbivory produced by crossing female BSB and male MC. The new hybrid offspring have great significance in aquatic applications.