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关于水产饲料中核苷酸及代谢产物的应用研究已开展了至少25年,结果表明,添加核苷酸能增加饲料的适口性,影响鱼类摄食行为和非必需氨基酸的合成。最新的研究表明,在水产养殖中,外源核苷酸的添加能显著增强鱼类机体免疫力、提高机体抗病力。也有研究发现,饲料中添加核苷酸能促进幼鱼早期组织发育,改变肠道结构、调节机体特异性和非特异性免疫来增强抗应激能力,也能通过增强亲鱼饵料的营养来强化幼鱼的体质。同时,饲料中添加核苷酸能增强鱼体对病毒、细菌和寄生虫的抗感染能力。尽管生理指标检测方面偶尔有不一致的表现,但饲料中添加核苷酸已经为诸多水产养殖品种带来效益。核苷酸营养在水产上的研究目前还处于初级阶段,尚有一些基础性问题没有得到解决。然而现有的研究结果足以表明,对于鱼类而言,核苷酸是半必需营养元素或条件性营养元素,还需要进一步开展更为深入的应用研究。核苷酸的作用体现在为合成能力有限的组织(如淋巴系统)提供原料,调节机体能量代谢和免疫内分泌作用,介导基因的表达模式调控等。因此,关于外源核苷酸在鱼类其它方面的应用研究如核苷酸消化、吸收、代谢及影响生理反应的方式(尤其是免疫相关基因的表达,免疫球蛋白的产生等),以及不同养殖品种的大小、阶段、使用剂量和添加时间等的研究都有待更为深入的研究。
Research on the use of nucleotides and metabolites in aquafeeds has been conducted for at least 25 years and the results show that addition of nucleotides increases the palatability of feeds and affects fish feeding behavior and the synthesis of nonessential amino acids. The latest research shows that in aquaculture, the addition of exogenous nucleotide can significantly enhance the immunity of fish and improve the disease resistance of the body. It has also been found that addition of nucleotides to feeds can promote early development of juvenile fish, alter intestinal architecture, regulate body-specific and nonspecific immunity to enhance resistance to stress, and enhance juvenile fish nutrition by enhancing brood stocking The constitution. In the meantime, addition of nucleotides to feed can enhance the fish’s ability to fight viruses, bacteria and parasites. Despite the occasional inconsistency in the detection of physiological indicators, the addition of nucleotides to feed has brought benefits to many aquaculture species. Nucleotide nutrition in aquatic research is still in its infancy, there are still some basic problems have not been solved. However, the existing research results are sufficient to show that, for fish, nucleotides are semi-essential nutrients or conditional nutrients, but also need to carry out more in-depth application of research. The function of nucleotides is to provide raw materials for organizations with limited synthetic capacity (such as the lymphatic system), to regulate the body’s energy metabolism and immune endocrine function, and to mediate the regulation of gene expression patterns. Therefore, the application of exogenous nucleotide in other aspects of fish such as nucleotide digestion, absorption, metabolism and the way to affect physiological responses (especially the expression of immune-related genes, immunoglobulin production, etc.), and different Research on the size, stage, dosage, and addition time of farmed species needs further study.