Pleuronectiformes, an order known as flatfishes, is important in mariculture worldwide with the unique characteristic of body asymmetry, and thus has value in scientific research. Also, as an economically important species, flatfishes have great developing potential for industrial aquaculture. Their rapid growth, rich nutrition, delicious taste, and high-quality protein are accepted and favoured by consumers all over the world. Due to large-scale breeding and expanding production, however, different degrees of abnormal body colour flatfishes have emerged, which seriously affect commercial value of the fish, even reducing it by half; therefore, relevant research has been carried out. This article reviews how environmental factors affect body colour abnormalities and possible genetic mechanism of abnormal body colouration of flatfishes, summarizes the hypotheses of the mechanism of body colour asymmetry, and proposes the latest improvement measures obtained at the genomic screening level to prevent the occurrence of abnormal body colour. This review suggests the molecular mechanism of abnormal asymmetric distribution of body colour, suggests measures for avoiding malpigmentation in flatfishes, and provides a constructive theoretical reference for healthy development of the flatfish breeding industry.

中文翻译：

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了解比目鱼的不对称色素沉着和水产养殖的改进措施

Pleuronectiformes是一种被称为比目鱼的目，在世界范围内具有重要的海水养殖价值，具有独特的身体不对称特征，因此具有科学研究价值。此外，比目鱼作为重要的经济物种，在工业化水产养殖中具有巨大的发展潜力。其生长迅速、营养丰富、味道鲜美、优质的蛋白质为世界各地的消费者所接受和青睐。但由于大规模养殖和扩大生产，出现了不同程度的体色异常比目鱼，严重影响了鱼的商业价值，甚至减少了一半；因此，进行了相关研究。本文综述了环境因素如何影响比目鱼体色异常及体色异常的可能遗传机制，总结了体色不对称机制的假设，并提出了在基因组筛查层面获得的最新改进措施，以防止体色异常的发生。本综述揭示了体色异常不对称分布的分子机制，提出了防止比目鱼色素异常的措施，为比目鱼养殖业的健康发展提供了建设性的理论参考。