Faculdade de Veterinária, Universidade Federal Fluminense, Rua Vital Brasil Filho, 64, Niterói, RJ CEP: 24320-340, Brazil.
Laboratório de Bacteriologia Veterinária, Instituto Biomédico, Niterói, Universidade Federal Fluminense, Alameda Barros Terra, 57, Niterói, RJ CEP: 24020-150, Brazil.
Vet Microbiol. 2022 Aug;271:109489. doi: 10.1016/j.vetmic.2022.109489. Epub 2022 Jun 6.
Leptospirosis in ruminants causes reproductive failures leading to important economic losses. This study assessed the occurrence and genetically identified Leptospira spp. in the follicular fluid (FF) of naturally infected live cows. A total of 251 asymptomatic cows from different commercial dairy herds were subjected to ovum-pick up technique for follicular fluid sampling. PCR was performed for Leptospira spp. detection and phylogenetic analysis was later implemented for sequencing. From 251 samples analyzed, 67 (26.7 %) were lipL32-PCR positive, confirming the presence of leptospiral DNA on FF. Furthermore, it was possible to amplify and sequence nine strains after secY nested-PCR. All of them were identified as L. interrogans, with 100 % of identity with strains belonging to Sejroe serogroup. Our findings reveal a high occurrence of infection of Leptospira in the ovarium of asymptomatic cows, highlighting the importance of considering the silent leptospirosis syndrome when screening animals for assisted reproductive biotechniques.
反刍动物中的钩端螺旋体病可导致生殖失败，造成重大经济损失。本研究评估了自然感染活牛卵泡液（FF）中钩端螺旋体属的发生情况和遗传鉴定。对来自不同商业奶牛场的 251 头无症状奶牛进行卵母细胞采集技术以采集卵泡液样本。进行了针对钩端螺旋体属的 PCR 检测，随后进行了测序的系统发育分析。在分析的 251 个样本中，67 个（26.7%）lipL32-PCR 呈阳性，证实 FF 中存在钩端螺旋体 DNA。此外，通过 secY 嵌套-PCR 可以扩增和测序 9 株。它们均被鉴定为 L. interrogans，与属于 Sejroe 血清群的菌株具有 100%的同一性。我们的研究结果表明，无症状奶牛卵巢中钩端螺旋体属的感染发生率很高，这凸显了在对动物进行辅助生殖生物技术筛查时考虑隐匿性钩端螺旋体病综合征的重要性。
