Histopatology of the reproductive tract of Nellore pubertal heifers with genital ureaplasmosis

ABSTRACT In order to study and characterize the lesions in the reproductive tract of Nellore heifers naturally infected with Ureaplasma diversum and presenting granular vulvovaginitis syndrome (GVS), fragments of uterine tube, uterus, cervix, vagina and vulva of 20 animals were evaluated. The macroscopic lesions of the vulvovaginal mucosa were classified in scores of “1” mild, until “4”, severe inflammation and pustular or necrotic lesions. The histopathological evaluation was performed using scores of “1” to “4”, according to the inflammatory alterations. The fragments with severe microscopic lesions (3 and 4) were from the uterine tubes and uterus, which showed leukocytes infiltration and destruction and/or necrosis of epithelium. Alterations in the lower reproductive tract fragments were mild, but characteristics of acute inflammatory processes. The histopathological findings of the reproductive tract of females naturally infected with Ureaplasma diversum are consistent with injuries that compromise the environment from the local where spermatozoa acquires ability to fertilize an oocyte until those where the oocyte is fertilized. Therefore, animals with GVS should be identified early in the herd, because, besides the reduction in the fertility rates caused by tissue damages, they can contribute to disseminate the microorganism. Key words: bovine, tissue evaluation, reproduction, Ureaplasma diversum.

摘要 为探究自然感染多样化脲原体（Ureaplasma diversum）且表现出颗粒性外阴阴道炎综合征（GVS）的奈洛尔青年母牛的生殖道损伤特征，本研究对20头试验个体的输卵管、子宫、宫颈、阴道及外阴组织样本进行了检测分析。研究人员将外阴阴道黏膜的大体病变按评分体系划分为1级（轻度）至4级（伴脓疱或坏死性病变的重度炎症）。组织病理学评估同样依据炎症变化程度，采用1至4级评分标准。微观病变等级为3级和4级的组织片段均取自输卵管与子宫，镜下可见白细胞浸润、上皮破坏及/或上皮坏死。下生殖道组织片段的病变程度较轻，但呈现急性炎症过程的典型特征。自然感染多样化脲原体（Ureaplasma diversum）的母牛生殖道组织病理学结果，与损害精子获能部位直至卵子受精部位的微环境的损伤特征一致。因此，牛群中应尽早筛查出患有颗粒性外阴阴道炎综合征（GVS）的个体：此类动物不仅会因组织损伤导致生育率下降，还可能促进该病原微生物的传播扩散。关键词：牛、组织评估、生殖、多样化脲原体（Ureaplasma diversum）