First breeding program of the Portuguese oyster Crassostrea angulata demonstrated significant selection response in traits of economic importance

• Published in: Aquaculture Vol. 518; p. 734664
• Main Authors: Vu, Sang V., Knibb, Wayne, Nguyen, Ngoc T.H., Vu, In V., O'Connor, Wayne, Dove, Michael, Nguyen, Nguyen Hong
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15-03-2020
• Subjects: Genetic correlation; Genetic improvement; Heritability; Oyster; Selection response and economic traits; Genetic correlation; Heritability; Selection response and economic traits; Oyster; Genetic improvement
• ISSN: 0044-8486; 1873-5622
• DOI: 10.1016/j.aquaculture.2019.734664

The Portuguese oyster Crassostrea angulata is one of the economically important mollusc species but to date there has been no genetic improvement program conducted for this species. The principal aim of this study was to assess genetic gains achieved from a selection program for improved whole weight at harvest over three generations from 2015 to 2017. A total of 30,212 oysters had performance data recorded; they were the offspring of 323 sires and 461 dams. Linear mixed models were used to estimate genetic parameters of the traits studied. Selection for improved harvest whole weight achieved significant direct response by 17.4% after three generations. There were also positively correlated changes in soft tissue weight and shell shape traits (3.67% and 3.98%, respectively). The genetic gains in harvest whole weight and favourably correlated changes in meat yield and shell shape traits were consistent with the positive genetic correlations of whole weight with these traits (0.08–0.50). There is abundant genetic variation in the selection criterion (heritability for whole weight = 0.24), suggesting that the present population of Portuguese oysters will continue showing responses to future selection. The estimates of heritability for meat yield and shell shape traits were low (0.10–0.16). Hence, a multi-trait selection program can be used to enhance overall productivity and economic return for oyster producers.
•First breeding program for Portuguese oysters yielded substantial direct response to selection for increased body weight.•The selection program also resulted in positive correlated changes in soft tissue weight and body shape traits.•Genetic correlations of harvest weight with meat yields and body shape traits were favourable to improve them simultaneously.•There were heritable genetic variations in meat yields and body shape traits.•Broadening the breeding objectives by including these new traits will maximise productivity and revenue for the sector.