Abstract To investigate the possible family influence on sea lice grazing of lumpfish on Atlantic salmon, ten families of lumpfish (N = 480) with a mean (± SD) weight of 54.8 ± 9.2 g were distributed among ten sea cages (5 × 5 × 5 m) each stocked with 400 Atlantic salmon with a mean (± SD) weight of 621.4 ± 9.2 g. All the ten cages were stocked with 48 lumpfish (12% stocking density). The stocking of cages was such that each cage consisted of two random families where full- and paternal half-sib families were randomly allocated to the different cages. There were clear differences in sea lice grazing efficacy, growth and cataract prevalence between the ten families assessed in this study. Lumpfish from families 2, 6 and 10 had the lowest mean weights but showed comparable growth rates compared to the other families throughout the study and this may be as a direct result of genetic influence. In addition, fish from these families had a significantly higher incidence of lice grazing of both L. salmonis and C. elongatus compared to the other families. Using mixed linear model to analyse the data revealed significant family and paternal effect on sea lice grazing. There was a trend for a reduction in sea lice grazing with increased size within each family. The results indicated that it was the smallest size classes of lumpfish (40–140 g) which exhibited higher sea lice grazing potential compared to the larger size classes within families. There were no clear differences in the lice grazing potential between male and female lumpfish within and between families. Overall, present findings showed that sea lice grazing of both L. salmonis and C. elongatus can be enhanced using targeted family production and if this behaviour has a genetic basis it may further enhanced through selection and targeted breeding programs.

中文翻译：

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不同鲽鱼科的放牧效率、生长和健康评分的量化：可能的大小和性别影响

摘要 为了研究鲽鱼对大西洋鲑鱼海虱放牧的可能影响，将平均（± SD）重量为 54.8 ± 9.2 g 的鲱鱼科（N = 480）分布在十个海网箱（5 × 5 × 5 m) 每条放养 400 条大西洋鲑鱼，平均 (± SD) 重量为 621.4 ± 9.2 g。所有 10 个网箱都放养了 48 条鲽鱼（12% 的放养密度）。笼子的放养是这样的，每个笼子由两个随机家庭组成，其中全同胞和父系半同胞家庭随机分配到不同的笼子。本研究评估的十个家庭在海虱放牧效率、生长和白内障患病率方面存在明显差异。来自家庭 2 的块鱼，6 和 10 的平均体重最低，但在整个研究过程中与其他家庭相比显示出可比的增长率，这可能是遗传影响的直接结果。此外，与其他科相比，来自这些科的鱼捕食 L.salmonis 和 C. elongatus 的虱子发生率明显更高。使用混合线性模型分析数据揭示了对海虱放牧的显着家庭和父系影响。随着每个家庭的体型增加，海虱的放牧量有减少的趋势。结果表明，与科内较大规格的鱼相比，最小规格的鲱鱼（40-140 克）表现出更高的海虱放牧潜力。在家庭内部和家庭之间，雄性和雌性鳐鱼之间的虱子放牧潜力没有明显差异。