INRA, UMR1313 Génétique Animale et Biologie Intégrative, F-78350 Jouy-en-Josas, France.
J Anim Sci. 2013 Jan;91(1):44-56. doi: 10.2527/jas.2012-5311. Epub 2012 Oct 16.
Aquaculture of carnivorous species has strongly relied on fish meal and fish oil for feed formulation; however, greater replacement by terrestrial plant-based products is occurring now. This rapid change in dietary environment has been a major revolution and has to be taken into consideration in breeding programs. The present study analyzes potential consequences of this nutritional tendency for selective breeding by estimating genetic parameters of BW and growth rates estimated by the thermal growth coefficient (TGC) over different periods with extremely different diets. European sea bass (Dicentrarchus labrax L.) from a factorial cross (1,526 fish) between 25 sires and 9 dams were used to estimate heritabilities and genotype by diet interaction. Starting 87 d after fertilization (2.5 g), one-half of the sea bass were fed a diet containing marine products (M), and the other one-half were fed a totally plant-based (PB) diet (without any fish meal or fish oil). The fish were individually tagged, reared in a recirculated system, and genotyped at 13 microsatellites to rebuild parentage of individuals. Body weight and TGC were measured for 335 d until fish fed the M diet reached 108.3 g of BW. These traits were significantly less in fish fed the PB diet (P<0.05) in the very first stages after the dietary shift, but the difference in TGC between diets rapidly disappeared (P>0.1). Survival was significantly less in fish fed the PB diet (PB=64.7%, M=93.7% after 418 d, P<0.05). This work identified moderate heritabilities (0.18 to 0.46) for BW with both diets and high genetic correlations between diets (0.78 to 0.93), meaning low genotype by diet interactions, although diets were extremely different. Heritabilities of TGC (0.11 to 0.3) were less than for BW as well as genetic correlations between diets (0.43 to 0.64). Using such extremely different diets, predicted BW gains in different scenarios indicated that selecting fish for growth on a marine diet should be the most efficient way to increase growth on plant-based diets, meaning that, in this case, indirect selection should be more efficient than direct selection.
肉食性鱼类的养殖强烈依赖于鱼粉和鱼油来配制饲料；然而，现在正在更多地用陆生植物性产品来替代它们。这种饮食环境的快速变化是一场重大革命，在养殖计划中必须考虑到这一点。本研究通过估计不同时期（采用截然不同的饲料）热生长系数（TGC）估算的体重和生长率的遗传参数，分析了这种营养趋势对选择性育种的潜在影响。使用 25 个父本和 9 个母本之间的因子杂交（1526 条鱼）的欧洲鲈鱼（Dicentrarchus labrax L.），来估计遗传力和基因型与饮食的互作。从受精后 87 天（2.5 克）开始，一半的鲈鱼喂食含有海产品的饲料（M），另一半喂食完全植物性饲料（PB）（不含任何鱼粉或鱼油）。这些鱼被单独标记，在循环系统中饲养，并在 13 个微卫星上进行基因分型，以重建个体的亲子关系。在 M 饲料喂养的鱼达到 108.3 克 BW 之前，对体重和 TGC 进行了 335 天的测量。在饮食改变后的最初阶段，PB 饲料喂养的鱼的体重和 TGC 明显更低（P<0.05），但两种饲料之间的 TGC 差异很快消失（P>0.1）。PB 饲料喂养的鱼的存活率明显较低（PB=64.7%，M=93.7%，418 天后，P<0.05）。这项工作确定了两种饲料的 BW 具有适度的遗传力（0.18 到 0.46），并且饲料之间存在很高的遗传相关性（0.78 到 0.93），这意味着基因型与饲料的互作较低，尽管饲料差异很大。TGC 的遗传力（0.11 到 0.3）低于 BW，以及饲料之间的遗传相关性（0.43 到 0.64）。使用如此截然不同的饲料，不同情景下的预测 BW 增益表明，选择在海洋饲料上生长的鱼类应该是提高植物性饲料上生长的最有效方式，这意味着在这种情况下，间接选择应该比直接选择更有效。
