Valeris-Chacin Robert, Powledge Sherri, McAtee Taylor, Morley Paul S, Richeson John
Veterinary Education, Research, and Outreach (VERO), Department of Veterinary Pathobiology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, United States.
Department of Agricultural Sciences, Paul Engler College of Agriculture and Natural Sciences, West Texas A&M University, Canyon, TX, United States.
Front Microbiol. 2022 Aug 1;13:946792. doi: 10.3389/fmicb.2022.946792. eCollection 2022.
Bovine Respiratory Disease (BRD) represents a significant burden to the health of feedlot cattle and the profitability of the beef industry in the US. is widely regarded as the primary bacterial pathogen driving acute BRD. While is most commonly implicated in chronic cases of BRD, this agent's potential role in acute stages of BRD is unclear. Therefore, this study aimed to evaluate potential associations between and during acute BRD in feedlot cattle. Nasal swabs ( = 1,044) were collected over time from feedlot cattle ( = 270) enrolled in an experiment assessing the effect of vaccination for Bovine Respiratory Syncytial Virus (BRSV). Swabs were analyzed for detection of , and BRSV multiplex qPCR assays. Data were analyzed using inverse conditional probability weighted (ICPW) logistic regression models to investigate potential effects of presence on arrival (d0), day seven (d7) and day 14 (d14) post-arrival on prevalence on day 28 (d28) post-arrival, adjusting for the previous history of , BRSV, BRD morbidity, and body weight. The potential association between time-to-BRD detection and presence on d0, d7, and d14 post-arrival, was inferred an ICPW time-to-event model. The presence of in nasal swabs collected on d7 post-arrival was significantly associated with an increase in the prevalence of on d28 (prevalence difference: 45%; 95% Confidence Interval: 31%, 60%; -value < 0.001). Significant time-varying coefficients for presence were detected at d0, d7, and d14 post-arrival in the ICPW time-to-event model (-value < 0.001). The shortest median time-to-BRD detection was 29 days in cattle that were positive on d0, d7, and d14 post-arrival and in those that were positive on d0 and d14 post-arrival. Under the conditions of this study, our findings suggest that may be influencing the respiratory environment during the acute phase of BRD, increasing the abundance of , which could have important impacts on the occurrence of BRD.
牛呼吸道疾病（BRD）对饲养场牛的健康以及美国牛肉行业的盈利能力构成了重大负担。[具体细菌名称1]被广泛认为是引发急性BRD的主要细菌病原体。虽然[具体细菌名称2]最常与BRD的慢性病例有关，但该病原体在BRD急性期的潜在作用尚不清楚。因此，本研究旨在评估饲养场牛急性BRD期间[具体细菌名称2]与[具体细菌名称1]之间的潜在关联。随着时间的推移，从参与评估牛呼吸道合胞病毒（BRSV）疫苗接种效果实验的饲养场牛（n = 270）中采集鼻拭子（n = 1,044）。对拭子进行分析，以检测[具体细菌名称1]、[具体细菌名称2]和BRSV的多重qPCR检测。使用逆条件概率加权（ICPW）逻辑回归模型分析数据，以研究到达时（d0）、到达后第7天（d7）和第14天（d14）[具体细菌名称2]的存在对到达后第28天（d28）[具体细菌名称1]患病率的潜在影响，并对[具体细菌名称2]、BRSV、BRD发病率和体重的既往病史进行调整。通过ICPW事件发生时间模型推断到达后d0、d7和d14时BRD检测时间与[具体细菌名称2]存在之间的潜在关联。到达后第7天采集的鼻拭子中[具体细菌名称2]的存在与第28天[具体细菌名称1]患病率的增加显著相关（患病率差异：45%；95%置信区间：31%，60%；P值<0.001）。在ICPW事件发生时间模型中，到达后d0、d7和d14检测到[具体细菌名称2]存在的显著时变系数（P值<0.001）。到达后d0、d7和d14呈[具体细菌名称2]阳性的牛以及到达后d0和d14呈阳性的牛中，最短的BRD检测中位时间为29天。在本研究条件下，我们的研究结果表明，[具体细菌名称2]可能在BRD急性期影响呼吸道环境，增加[具体细菌名称1]的丰度，这可能对BRD的发生产生重要影响。
