An 88-day feeding trial was conducted to evaluate the effects of dietary inosine 5′-monophosphate (5′-IMP) on the growth performance and salinity and oxidative stress resistance in the juvenile gibel carp CAS III (Carassius auratus gibelio; initial body weight: 7.48 g). Four isonitrogenous and isoenergetic diets containing exogenous 5′-IMP were formulated. P1, P2, P3 and P4 were diets containing 5′-IMP at four concentrations (0, 1, 2 and 4 g kg−1). The four diets were randomly allotted to triplicate tanks in a recirculating system. After the feeding trial, six fish per tank were netted randomly and placed into 12‰ saline water to test their response to salinity stress. The results indicated that the feed conversion rate was enhanced by dietary supplementation with 5′-IMP. The appetite, plasma neuropeptide Y level and feeding rate of the P3 group were lower than those in the control treatment group. Dietary supplementation with 5′-IMP improved the osmoregulatory adaptation of gibel carp under acute salinity stress. Six hours after the salinity stress treatment, in the dietary 5′-IMP treatment group, the plasma cortisol and K+ concentrations were lower and the Na+/K+-ATPase activity was greater than that in the control group. Dietary supplementation with 5′-IMP promoted the expression of the glucocorticoid receptors NKA-α1b and NKCC and retarded the expression of Hsp70 in P4-treated gill filaments and kidneys. Dietary supplementation with 5′-IMP resulted in a stable oxidative-stress-resistant phenotype characterized by increased levels of cellular antioxidants, including SOD, catalase, glutathione peroxidase, glutathione reductase and MPO. The above results of the current study demonstrate that supplementation of 5′-IMP can promote feed utilization and have positive influences on the salinity and oxidative stress resistance of gibel carp.

中文翻译：

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日粮添加肌苷5'-单磷酸盐对银鲫生长性能及耐盐性和氧化应激能力的影响

通过为期 88 天的饲养试验，评估膳食肌苷 5'-单磷酸 (5'-IMP) 对银鲫 CAS III 幼鱼（Carassius auratus gibelio；初始体重）生长性能、盐度和氧化应激抵抗力的影响。 ：7.48 克）。配制了四种含有外源 5'-IMP 的等氮和等能量饮食。 P1、P2、P3 和 P4 是含有四种浓度（0、1、2 和 4 g kg−1）5'-IMP 的日粮。这四种饮食被随机分配到再循环系统中的三个重复罐中。饲养试验结束后，随机网捕每缸6条鱼，放入12‰盐水中，测试其对盐胁迫的反应。结果表明，日粮中添加5'-IMP可提高饲料转化率。 P3组的食欲、血浆神经肽Y水平和摄食率均低于对照组。饲料中添加5'-IMP可改善银鲫在急性盐胁迫下的渗透调节适应能力。盐胁迫处理后6小时，饮食5′-IMP处理组血浆皮质醇和K+浓度低于对照组，Na+/K+-ATP酶活性高于对照组。膳食补充 5'-IMP 促进了 P4 处理的鳃丝和肾脏中糖皮质激素受体 NKA-α1b 和 NKCC 的表达，并延迟了 Hsp70 的表达。膳食补充 5'-IMP 可产生稳定的抗氧化应激表型，其特征是细胞抗氧化剂水平增加，包括 SOD、过氧化氢酶、谷胱甘肽过氧化物酶、谷胱甘肽还原酶和 MPO。本研究的上述结果表明，添加5'-IMP可以促进饲料利用率，对银鲫的盐度和氧化应激抵抗能力产生积极影响。