Abstract:
Samples from the mesenteric lymph nodes (MS LNs) and ileocecal valves (ICV) of 105 goats, comprising 61 non-vaccinated and 44 vaccinated against Mycobacterium avium subspecies paratuberculosis (MAP), were collected at slaughter from a farm with a confirmed history of paratuberculosis (PTB). These goats had subclinical infections. PTB-compatible lesions in the MS LNs, ICV lamina propria (LP), and Peyer\'s patches (PPs) were graded separately. Furthermore, the load of acid-fast bacilli was quantified using Ziehl-Neelsen staining (ZN), MAP antigens by immunohistochemistry (IHC), and MAP DNA by PCR targeting the IS900 sequence. Gross PTB-compatible lesions were found in 39% of the goats, with 31.72% vaccinated (V) and 68.29% non-vaccinated (nV). Histopathological lesions induced MAP were observed in 58% of the animals, with 36.07% vaccinated and 63.93% non-vaccinated. The inclusion of histopathology as a diagnostic tool led to a 28% increase in diagnosed cases in MS LNs and 86.05% in ICV. Grade IV granulomas with central mineralization and necrosis were the most common lesions in MS LNs. In the ICV, mild granulomatous enteritis with multifocal foci of epithelioid macrophages was predominant, occurring more frequently in the PPs than in the LP. Furthermore, statistical differences in the presence of histopathological lesions between vaccinated and non-vaccinated goats were noted in MS LNs, ICV LPs, and ICV PPs. Non-vaccinated animals showed higher positivity rates in ZN, IHC, and PCR tests, underscoring the benefits of anti-MAP vaccination in reducing PTB lesions and bacterial load in target organs. Our findings emphasize the necessity of integrating gross and histopathological assessments with various laboratory techniques for accurate morphological and etiological diagnosis of PTB in both vaccinated and non-vaccinated goats with subclinical disease. However, further studies are required to refine sampling protocols for subclinical PTB in goats to enhance the consistency of diagnostic tools.
摘要:
来自105只山羊的肠系膜淋巴结(MSLNs)和回盲瓣(ICV)的样本,包括61个未接种疫苗和44个接种疫苗的鸟分枝杆菌副结核亚种(MAP),在屠宰时从确认有副结核病(PTB)病史的农场收集。这些山羊有亚临床感染。MSLN的PTB相容性病变,ICV固有层(LP),和Peyer的补丁(PPs)分别进行分级。此外,使用Ziehl-Neelsen染色(ZN)定量抗酸杆菌的负荷,通过免疫组织化学(IHC)的MAP抗原,和MAPDNA通过PCR靶向IS900序列。在39%的山羊中发现了与PTB相容的总体病变,31.72%接种疫苗(V)和68.29%未接种疫苗(nV)。在58%的动物中观察到组织病理学损伤诱导的MAP,36.07%接种疫苗,63.93%未接种疫苗。纳入组织病理学作为诊断工具导致MSLN的诊断病例增加28%,ICV的诊断病例增加86.05%。伴有中央矿化和坏死的IV级肉芽肿是MSLNs中最常见的病变。在ICV中,轻度肉芽肿性肠炎以多灶性上皮样巨噬细胞灶为主,在PP中比在LP中更频繁地发生。此外,在MSLN中注意到接种和未接种的山羊之间存在组织病理学病变的统计学差异,ICVLP,和ICVPPs。未接种疫苗的动物在ZN中显示出更高的阳性率,IHC,和PCR测试,强调抗MAP疫苗在减少靶器官PTB病变和细菌负荷方面的益处。我们的发现强调了将总体和组织病理学评估与各种实验室技术相结合的必要性,以对接种和未接种亚临床疾病的山羊进行PTB的准确形态学和病因诊断。然而,需要进一步的研究来完善山羊亚临床PTB的采样方案,以提高诊断工具的一致性.