Hainan Key Laboratory for Conservation and Utilization of Tropical Marine Fishery Resources, Sanya, 572022, Hainan province, People's Republic of China.
College of Fisheries and Life Science, Hainan Tropical Ocean University, Sanya, 572022, Hainan Province, People's Republic of China.
Fish Physiol Biochem. 2020 Dec;46(6):2037-2053. doi: 10.1007/s10695-020-00851-3. Epub 2020 Aug 7.
Plant proteins are suitable and alternative to fish meals (FMs), with less cost compared with that of all other types of fish feeds. In recent years, soy protein concentrate (SPC) has emerged as a cost-effective alternative to FM; however, little is known regarding the effects of dietary SPC on general fish physiology and well-being. This study aimed to perform comprehensive physiological and transcriptomic analysis for testing the applicability of SPC as fish feeds in hybrid grouper (Epinephelus fuscoguttatus♀ × E. lanceolatus♂) [SPC replaced 0% (CK), 30% (SPC30), and 75% (SPC75) of FM protein]. Generally, SPC30 promoted fish survival and had less effects on the phenotype, while SPC75 reduced fish survival, promoted inflammation, and regulated multiple physiological responses. Thousands of differentially expressed genes (DEGs) by SPC were identified in the intestine, liver, and muscle, which were enriched in biological regulation, cellular process, metabolic process, single-organism process, cell, cell part, membrane, binding, and catalytic activity based on RNA-seq. Notably, some DEGs involved in amino acid and lipid metabolism in the digestive system highlighted the modulatory effect of SPC on these metabolic processes, consistent with the physiological responses including enzyme activities. The enriched aspects of these predominant DEGs might be directly related to the different effects of SPC30 and SPC75 on fish growth, digestibility, and underlying enzyme activities and histology. In conclusion, the comprehensive physiological and transcriptomic comparative analysis of CK, SPC30, and SPC75 was also effective in testing the applicability of SPC as fish feeds and in designing a proper diet with the best impact on the growth performance and health of fish in hybrid grouper.
植物蛋白是鱼粉（FM）的合适替代品，成本比其他类型的鱼饲料都低。近年来，浓缩大豆蛋白（SPC）已成为 FM 的一种具有成本效益的替代品；然而，关于 SPC 对鱼类一般生理和健康的影响，人们知之甚少。本研究旨在进行全面的生理和转录组分析，以测试 SPC 作为杂交石斑鱼（♀Epinephelus fuscoguttatus×♂E. lanceolatus）饲料的适用性[SPC 替代 0%（CK）、30%（SPC30）和 75%（SPC75）的 FM 蛋白]。一般来说，SPC30 提高了鱼类的存活率，对表型的影响较小，而 SPC75 降低了鱼类的存活率，促进了炎症，并调节了多种生理反应。通过 SPC 在肠道、肝脏和肌肉中鉴定了数千个差异表达基因（DEGs），这些基因在 RNA-seq 基础上富集在生物调节、细胞过程、代谢过程、单一生物过程、细胞、细胞部分、膜、结合和催化活性。值得注意的是，一些参与消化系统氨基酸和脂质代谢的 DEGs 强调了 SPC 对这些代谢过程的调节作用，这与包括酶活性在内的生理反应一致。这些主要 DEGs 所富集的方面可能与 SPC30 和 SPC75 对鱼类生长、消化率以及潜在酶活性和组织学的不同影响直接相关。总之，对 CK、SPC30 和 SPC75 的综合生理和转录组比较分析也有效地测试了 SPC 作为鱼类饲料的适用性，并设计了一种适当的饮食，对杂交石斑鱼的生长性能和健康产生最佳影响。
