A genotype-by-environment (G × E) interaction is defined as genotypes responding differently to different environments. In salmonids, G × E interactions can occur in different rearing conditions, including changes in salinity or temperature. However, water flow, an important variable that can influence metabolism, has yet to be considered for potential G × E interactions, although water flows differ across production stages. The salmonid industry is now manipulating flow in tanks to improve welfare and production performance, and expanding sea pen farming offshore, where flow dynamics are substantially greater. Therefore, there is a need to test whether G × E interactions occur under low and higher flow regimes to determine if industry should consider modifying their performance evaluation and selection criteria to account for different flow environments. Here, we used genotype-by-sequencing to create a genomic-relationship matrix of 37 Chinook salmon, Oncorhynchus tshawytscha, families to assess possible G × E interactions for production performance under two flow environments: a low flow regime (0.3 body lengths per second; bl s−1) and a moderate flow regime (0.8 bl s−1). Genetic correlations for the same production performance trait between flow regimes suggest there is minimal evidence of a G × E interaction between the low and moderate flow regimes tested in this study, for Chinook salmon reared from 82.9 ± 16.8 g ( $${\overline{\text{x}}}$$ ± s.d.) to 583.2 ± 117.1 g ( $${\overline{\text{x}}}$$ ± s.d.). Estimates of genetic and phenotypic correlations between traits did not reveal any unfavorable trait correlations for size- (weight and condition factor) and growth-related traits, regardless of the flow regime, but did suggest measuring feed intake would be the preferred approach to improve feed efficiency because of the strong correlations between feed intake and feed efficiency, consistent with previous studies. This new information suggests that Chinook salmon families do not need to be selected separately for performance across different flow regimes. However, further studies are needed to confirm this across a wider range of fish sizes and flows. This information is key for breeding programs to determine if separate evaluation groups are required for different flow regimes that are used for production (e.g., hatchery, post smolt recirculating aquaculture system, or offshore).

中文翻译：

---

在低流量和中等流量条件下饲养的奇努克鲑鱼生长和饲料效率相关性状的遗传参数和基因型与环境相互作用估计


基因型与环境（G × E）的相互作用被定义为基因型对不同环境的不同反应。在鲑鱼中，G × E 相互作用可以在不同的饲养条件下发生，包括盐度或温度的变化。然而，尽管水流量在不同生产阶段有所不同，但水流量是影响新陈代谢的重要变量，尚未考虑潜在的 G × E 相互作用。鲑科鱼产业现在正在控制水箱中的流量，以提高福利和生产绩效，并扩大海上围栏养殖，那里的流量动态要大得多。因此，需要测试在低流量和高流量状态下是否会发生 G × E 相互作用，以确定工业界是否应考虑修改其性能评估和选择标准以适应不同的流量环境。在这里，我们使用基因型测序创建了 37 个奇努克鲑鱼 (Oncorhynchus tshawytscha) 家族的基因组关系矩阵，以评估两种流动环境下生产性能可能的 G × E 相互作用：低流动状态（每秒 0.3 个体长） ; bl s−1) 和中等流动状态 (0.8 bl s−1)。不同流态之间相同生产性能特征的遗传相关性表明，对于从 82.9 ± 16.8 g 饲养的奇努克鲑鱼（$${\overline{ \text{x}}}$$ ± sd) 至 583.2 ± 117.1 g ($${\overline{\text{x}}}$$ ± sd)。 对性状之间的遗传和表型相关性的估计并未揭示任何与尺寸（重量和条件因素）和生长相关性状相关的不利性状相关性，无论流态如何，但确实表明测量采食量将是改善饲料的首选方法效率，因为采食量和饲料效率之间存在很强的相关性，这与之前的研究一致。这一新信息表明，不需要针对不同流态下的性能单独选择奇努克鲑鱼家族。然而，还需要进一步的研究来在更广泛的鱼类尺寸和流量范围内证实这一点。该信息对于育种计划至关重要，以确定用于生产的不同流型（例如孵化场、小鲑鱼后循环水产养殖系统或近海）是否需要单独的评估组。