Encinas Micaela, Ferrara Muñiz Ximena, Sammarruco Romina Ayelén, Ruiz Menna Victoria, Garro Carlos Javier, Delgado Fernando, Macías Analía, Magnano Gabriel, Zumárraga Martín José, Garbaccio Sergio Gabriel, Eirin María Emilia
Instituto de Agrobiotecnología y Biología Molecular (IABiMo) UEDD CONICET-INTA, Centro de Investigación en Ciencias Veterinarias y Agronómicas (CICVyA)-CNIA, Hurlingham, Argentina.
Instituto de Patobiología Veterinaria (IPVET), UEDD CONICET-INTA, Instituto Nacional de Tecnología Agropecuaria (INTA), INTA-CONICET, Hurlingham, Argentina.
Front Vet Sci. 2024 May 20;11:1359205. doi: 10.3389/fvets.2024.1359205. eCollection 2024.
Ante-mortem diagnosis of bovine tuberculosis (bTB) is based mainly on the tuberculin skin test (TST) and the ɣ-IFN release assay (IGRA). Some infected animals escape screening tests, thus, limit herd sanitation. Previous reports have suggested a predominant pattern of multi-organ lesions attributable to (the causative agent of bTB) bacteraemia. A case-control study was conducted to investigate blood PCR as an alternative tool for improving ante-mortem detection of TST false-negative bovines. Cases comprised 70 TST false-negative bovines (cases), which were serology positive, and controls included 81 TST positive bovines; all of them confirmed as infected with . Detection of the IS target through touchdown blood-PCR (IS TD-PCR) was performed. The positivity of the blood-PCR was 27.2% in the control group. This performance was similar to the 15% obtained among cases ( = 0.134). Most cases identified by the IS TD-PCR exhibited focalized lesions ( = 0.002). Results demonstrated that blood-PCR could detect TST false-negative cattle, even if they are negative for IGRA. Considering that cases exhibited humoral response to , further studies conducted in a pre-serological stage could provide evidence about the real contribution of the technique in herds.
牛结核病（bTB）的生前诊断主要基于结核菌素皮肤试验（TST）和γ-干扰素释放试验（IGRA）。一些受感染的动物会逃过筛查测试，因此限制了畜群卫生状况。先前的报告表明，由牛结核病的病原体引起的菌血症会导致多器官病变的主要模式。开展了一项病例对照研究，以调查血液PCR作为一种改进TST假阴性牛生前检测的替代工具。病例包括70头TST假阴性牛（病例组），这些牛血清学呈阳性，对照组包括81头TST阳性牛；所有这些牛均确诊感染了[病原体名称未给出]。通过降落式血液PCR（IS TD-PCR）检测IS靶标。对照组血液PCR的阳性率为27.2%。该表现与病例组中获得的15%相似（P = 0.134）。IS TD-PCR鉴定出的大多数病例表现为局灶性病变（P = 0.002）。结果表明，血液PCR可以检测出TST假阴性牛，即使它们IGRA呈阴性。考虑到病例对[病原体名称未给出]表现出体液反应，在血清学前期进行的进一步研究可以提供有关该技术在畜群中实际作用的证据。
