Poonsuk Korakrit, Kordik Carita, Hille Matthew, Cheng Ting-Yu, Crosby William B, Woolums Amelia R, Clawson Michael L, Chitko-McKown Carol, Brodersen Bruce, Loy John Dustin
Nebraska Veterinary Diagnostic Center, School of Veterinary Medicine and Biomedical Sciences, University of Nebraska-Lincoln, Lincoln, NE 68503, USA.
Department of Veterinary Preventive Medicine, College of Veterinary Medicine, The Ohio State University, Columbus, OH 43210, USA.
Animals (Basel). 2023 May 3;13(9):1531. doi: 10.3390/ani13091531.
is one of the major causes of bovine respiratory disease in cattle. The organism is the primary bacterium isolated from calves and young cattle affected with enzootic pneumonia. Novel indirect ELISAs were developed and evaluated to enable quantification of antibody responses to whole cell antigens using A1 strain P1148. In this study, the ELISAs were initially developed using sera from both -culture-free and clinically infected cattle, then the final prototypes were tested in the validation phase using a larger set of known-status sera ( = 145) collected from feedlot cattle. The test showed good inter-assay and intra-assay repeatability. Diagnostic sensitivity and specificity were estimated at 91% and 87% for IgG at a cutoff of S/P ≥ 0.8. IgM diagnostic sensitivity and specificity were 91% and 81% at a cutoff of sample to positive (S/P) ratio ≥ 0.8. IgA diagnostic sensitivity was 89% whereas specificity was 78% at a cutoff of S/P ≥ 0.2. ELISA results of all isotypes were related to the diagnosis of respiratory disease and isolation of (-value < 0.05). These data suggest that ELISAs can be adapted to the detection and quantification of antibody in serum specimens and support the use of these tests for the disease surveillance and disease prevention research in feedlot cattle.
是牛群中牛呼吸道疾病的主要病因之一。该病原体是从患有地方流行性肺炎的犊牛和幼牛中分离出的主要细菌。开发并评估了新型间接酶联免疫吸附测定法（ELISA），以使用A1菌株P1148对全细胞抗原的抗体反应进行定量。在本研究中，ELISA最初使用来自无培养物和临床感染牛的血清进行开发，然后在验证阶段使用从饲养场牛收集的大量已知状态血清（n = 145）对最终原型进行测试。该测试显示出良好的批间和批内重复性。当临界值为S/P≥0.8时，IgG的诊断敏感性和特异性估计分别为91%和87%。当临界值为样本与阳性（S/P）比值≥0.8时，IgM的诊断敏感性和特异性分别为91%和81%。当临界值为S/P≥0.2时，IgA的诊断敏感性为89%，而特异性为78%。所有同种型的ELISA结果均与呼吸道疾病的诊断和该病原体的分离相关（P值<0.05）。这些数据表明，ELISA可适用于血清标本中抗体的检测和定量，并支持将这些检测用于饲养场牛的疾病监测和疾病预防研究。
