Identification of gynogenetic Megalobrama amblycephala induced by red crucian carp sperm and establishment of a new hypoxia tolerance strain.

Blunt snout bream (BSB) is an important economic freshwater fish in China. One of technical bottlenecks in practice lies in improving its hypoxia tolerance. In this study, gynogenesis BSB (GBSB-R) is generated by artificial gynogenesis with UV-inactivated sperms of red crucian carp (RCC), which is regarded as one of freshwater fish with the strongest hypoxia-tolerance. Asynchronous development of the eye pigment further provides an objective morphologic evidence of distinguishing the gynogenesis BSB progeny with the hybrids of BSB (♀) × RCC (♂). It is found that the GBSB-R is a kind of all-female population with normal fertility and its genetic homozygosity is higher than that of wildtype BSB. In view of hypoxia stress tests, physiological indexes and gene expression, the obtained experimental data from this research confirm that the GBSB-R is a new strain with improved hypoxia tolerance, especially compared with the wildtype BSB. These results indicate that artificial gynogenesis is an efficient method to enlarge capacity of the BSB hypoxia tolerance, and the conducted research in this article is valuable to the practical aquaculture. • Gynogenesis blunt snout bream (GBSB-R) generated with UV-inactivated sperms of red crucian carp (RCC) • GBSB-R is a new strain with higher genetic homozygosity and stronger hypoxia tolerance than blunt snout bream (BSB) • An objective evidence to distinguish GBSB-R progeny with hybrids of BSB x RCC by asynchronous development of eye pigments [ABSTRACT FROM AUTHOR]