Improvement in production traits by mass spawning type crossbreeding in bay scallops

Bay scallop culture has become a major sector in marine culture industry in China since its first introduction in early 1980s. However, despite various efforts including several re-introductions, decreases in major production traits such as survival and growth rates are still a major concern to the industry. This study aimed to evaluate the performance of offspring derived from mass spawning type crossbreeding between different populations in bay scallops. The results showed that significant differences in growth and survival existed among the four intra-population crosses at larval stages, but not at the adult stage. Increases in growth and survival rates were observed in most inter-population crosses at larval stages and in all inter-population crosses at the adult stage. The survival rate of the best inter-population crosses was 156.7% higher than the average survival rate of all the intra-population crosses. Through mass spawning type crossbreeding between different populations, we were able to produce offspring with improved production traits and the results may have immediate application in bay scallop culture.