Characteristics of hybrids derived from Channa argus ♀ × Channa maculata ♂

Interspecific hybridization has been used as an important tool for genetic manipulation in aquaculture, with the goal of obtaining new strains with desired traits from both parental species. In this study, a hybrid strain was established by Channa argus (NS) (♀) and Channa maculata (BS) (♂), named NBS hybrid snakehead (NBS). A comparison of the morphological characteristics (meristic and measurable traits), ploidy (DNA content and karyotype), and aquaculture performance (growth and low-temperature tolerance) were examined. NBS resembled the male parent (BS) in body stripes and body shape and had moderate values for its meristic traits. Flow cytometry indicated that NBS is diploid, and the karyotype confirmed that the number of chromosomes in NBS (2n = 45) was between that in NS (2n = 48) and that in BS (2n = 42). In addition, NBS showed significantly higher growth rates compared to its parents. Under the same feeding conditions, the average body weight of NBS was 421.3 ± 72.9 g at six months of age, which was significantly greater than NS (187.6 ± 42.8 g) and BS (245.6 ± 52.5 g) by 124.6% and 71.53%, respectively (P < 0.05). The overwintering culture test proved that there were no significant differences in the low-temperature tolerance between NS and NBS (P > 0.05), and both lived through the winter when the water temperature dropped to 0-2 °C. In general, NBS is easily trained to accept commercial feed (a characteristic of BS) and has fast growth rate and strong low-temperature tolerance (characteristics of NS), and it will be a valuable new strain for the aquaculture industry.