Abstract：
This study investigated the effects of yeast hydrolysate (YH) from sugar byproducts on various parameters in Pacific white shrimp (Litopenaeus vannamei). The study found no significant differences in water quality parameters across all treatment tanks, ensuring that the observed effects were not due to environmental variations. There were no significant differences in growth parameters between the control group and groups receiving YH at different dosages. However, the group given YH at 10.0 g/kg feed exhibited a notably higher survival rate and higher expression of growth-related genes (IGF-2 and RAP-2A) in various shrimp tissues. YH was associated with enhanced immune responses, including lysozyme activity, NBT dye reduction, bactericidal activity, and phagocytic activity. Notably, the 10.0 g/kg feed group displayed the highest phagocytic index, indicating a dose-dependent immune response. Expression of immune-related genes (ALF, LYZ, ProPO, and SOD) was upregulated in various shrimp tissues. This upregulation was particularly significant in the gills, hepatopancreas, intestine, and hemocytes. While total Vibrio counts remained consistent, a reduction in green Vibrio colonies was observed in the intestine of shrimp treated with YH. YH, especially at 5.0 and 10.0 g/kg feed dosages, significantly increased survival rates and RPS values in response to AHPND infection. The findings of this study suggest that incorporating additives derived from yeast byproducts with possible prebiotic properties obtained from sugar byproducts can lead to positive results in terms of enhancing growth performance, immunity, histological improvements, and resistance to V. parahaemolyticus, the causative agent of acute hepatopancreatic necrosis disease (AHPND).
摘要：
这项研究调查了来自糖副产物的酵母水解物（YH）对太平洋白虾（凡纳滨对虾）各种参数的影响。研究发现，所有处理池的水质参数没有显着差异，确保观察到的影响不是由于环境变化。对照组和接受不同剂量YH的组之间的生长参数没有显着差异。然而,以10.0g/kg饲料给予YH的组在各种虾组织中表现出明显更高的存活率和更高的生长相关基因（IGF-2和RAP-2A）表达。YH与增强的免疫反应有关，包括溶菌酶活性，NBT染料还原,杀菌活性，和吞噬活性。值得注意的是,10.0g/kg饲料组的吞噬指数最高，表明剂量依赖性免疫反应。免疫相关基因的表达（ALF，LYZ,ProPO,和SOD）在各种虾组织中上调。这种上调在the中尤其明显，肝胰腺,肠,和血细胞。虽然弧菌总数保持一致，在用YH处理的虾的肠中观察到绿色弧菌菌落减少。YH,特别是在5.0和10.0g/kg饲料剂量下，显着提高了对AHPND感染的存活率和RPS值。这项研究的结果表明，掺入从酵母副产品中获得的具有可能的益生元特性的添加剂可以在增强生长性能方面产生积极的结果。豁免权,组织学改善，以及对副溶血性弧菌的抗性,急性肝胰腺坏死病（AHPND）的病原体。
