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：为研究并表征自然感染多样化脲原体（Ureaplasma diversum）并表现出颗粒性阴道炎综合征（granular vulvovaginitis syndrome, GVS）的内洛尔青年母牛生殖道病变特征，本研究对20头受试动物的输卵管、子宫、宫颈、阴道及外阴组织片段开展评估。将外阴阴道黏膜的肉眼病变划分为1至4个等级：1分为轻度炎症，4分为重度炎症伴脓疱或坏死性病变。组织病理学评估同样采用1至4分的评分体系，依据炎症改变程度进行分级。微观病变严重（3级及4级）的组织片段取自输卵管与子宫，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，但具备急性炎症过程的特征。自然感染多样化脲原体的雌性个体生殖道组织病理学结果，与损害精子获能位点直至卵子受精位点的微环境的损伤特征一致。因此，牛群中应早期识别颗粒性阴道炎综合征（GVS）患牛：此类个体不仅会因组织损伤导致生育率下降，还可能促进该病原体的传播。关键词：牛、组织评估、生殖、多样化脲原体（Ureaplasma diversum）