奶牛产后感染性子宫疾病对子宫和卵巢的影响研究进展

微生物入侵是引起奶牛产后子宫疾病的主要因素,产后子宫能检出丰富的微生物种群,主要包括公认的致病菌如大肠杆菌、隐秘脓杆菌、坏死梭杆菌等,机会病原菌如产气荚膜梭菌、肺炎克雷伯菌、微球菌等和潜在致病菌如消化链球菌、金黄色葡萄球菌等。近年来,运用分子微生态技术发现子宫中的微生物属于变形菌门、梭杆菌门、厚壁菌门、拟杆菌门和软壁菌门5个已知的门和一类未被培养的种群,其中拟杆菌属、梭菌属等种群与子宫疾病密切相关。细菌侵入子宫后,以大肠杆菌为代表的革兰氏阴性菌和以化脓隐秘杆菌为代表的革兰氏阳性菌可被子宫内膜细胞上的Toll样受体识别引起炎症反应,改变子宫前列腺素分泌类型,影响卵泡发育、黄体大小,降低血清中雌激素和孕激素浓度,造成奶牛不发情、不排卵,导致产犊间隔延长、产奶量和产犊数量下降,严重影响奶业经济效益。本文从产后奶牛子宫内主要病原菌的种类及其与子宫健康状态的关系、子宫内膜对病原菌的识别与先天免疫、子宫疾病对子宫和卵巢功能的影响等方面对国内外研究进展进行了综述。

Advances of the effects of infectious uterine disease on uterus and ovary in postpartum dairy cow

Infectious uterine diseases are mainly caused by bacteria invasion following parturition in dairy cows. A wide range of bacteria population were revealed in the postpartum uterus of cattle, including recognized uterine pathogens such as Escherichia coli, Arcanobacterium pyogenes, Fusobacterium necrophorum; potential pathogens such as Clostridium perfringens, Klebsiella pneumoniae, Micro Streptococcus; opportunist pathogens such as Peptostreptococcus, Staphylococcus aureus. Recently, phyla of Proteobacteria, Fusobacteria, Firmicutes, Bacteroidetes, Tenericutes and a group of uncultured bacteria were observed in the uteri using molecular biology techniques. A positive correlation were found between Bacteroides, Fusobacterium and uterine diseases. G? bacteria, E. coli as representative, and G+ bacteria, A. pyogenes as representative can be detected by Toll like receptors in the endometrial cell membrane and subsequently resulted in inflammation responses, such as changes in prostaglandins type, small size of follicle and corpus luteum, reduction in serum concentration of estrogen and progesterone. Finally, this led to anestrus and anovulation, prolonged calving interval, lowing milk yield and the number of calves, which largely reduced economic profit. This review outlines the dominant microbial community in uterus after calving, correlations between bacterial species and the uterus status, recognitions of pathogen in endometrium and innate immunity, effects of uterine diseases on ovary and uterus function.