猪β防御素研究进展

β防御素是猪体内分泌的一类抗菌肽，广泛分布于各个组织中，在抵抗病原入侵和免疫调节中发挥着重要作用。猪β防御素对细菌、真菌和病毒都有很强的杀灭作用，并且具有分子量小、热稳定性好、无残留等优点，是理想的抗生素替代品。研究表明，猪β防御素的表达与个体抗病力正相关，增加内源性防御素表达或直接摄入外源性防御素均能增强机体免疫力并促进生长。脂肪酸、氨基酸、维生素、益生菌、病原微生物等外源刺激皆可影响β防御素的表达。随着防御素相关研究的深入，将有望解决养猪生产中长期使用抗生素而导致的耐药性、药物残留及环境污染等问题。文章介绍了猪β防御素的结构特征、表达特异性及生物学功能，主要综述了外源刺激对β防御素表达的影响及其作用机制，初步说明外源β防御素作为饲料添加剂在仔猪生产中的效果，旨在为猪β防御素的深入研究及其在生猪健康养殖中的应用提供参考。

Research Advance on Procine β Defensins

β defensins are a class of antimicrobial peptides secreted by pigs.They are widely distributed in tissues and play an important role in resisting pathogenic microorganism and immune regulation.Porcine β defensins have strong inhibitive activity against bacteria, fungi and viruses, and have the advantages of small molecular weight, high heat stability and no residue, making them an ideal antibiotic substitute.Researches have showed that the expression of porcine β defensins positively correlate with disease resistance.It can enhance immunity and promote growth of pigs by increasing the expression of endogenous defensins or ingesting exogenous defensins.Exogenous stimulus such as fatty acids, amino acids, vitamins, probiotics and microorganisms could affect the expression of β defensins.With the deep researches of defenses, they are expected to solve the problems of drug resistance, drug residues and environmental pollution caused by long-term use of antibiotics in pig production.This paper reviews recent advances in porcine β defensins, including structure characteristics, expression specificity and biological function.The effects of exogenous stimuli on the expression of defensins and their mechanisms are mainly reviewed.The preliminary applications of exogenous β defensins as feed additives in piglet production are analyzed in order to lay the foundation for pig β defensins researches and their application in healthy pig breeding.