PDF(Pubmed)
Abstract：
Bovine respiratory disease (BRD) is one of the most common diseases in the cattle industry; it is a globally prevalent multifactorial infection primarily caused by viral and bacterial coinfections. In China, Mycoplasma bovis (M. bovis) and bovine herpesvirus type 1 (BoHV-1) are the most notable pathogens associated with BRD. Our previous study attempted to combine the two vaccines and conducted a preliminary investigation of their optimal antigenic ratios. Based on this premise, the research extended its investigation by administering varying vaccine doses in a rabbit model to identify the most effective immunization dosage. After immunization, all rabbits in other immunization dose groups had a normal rectal temperature without obvious clinical symptoms. Furthermore, assays performed on the samples collected from immunized rabbits indicated that there were increased humoral and cellular immunological reactions. Moreover, the histological analysis of the lungs showed that immunized rabbits had more intact lung tissue than their unimmunized counterparts after the challenge. Additionally, there appears to be a positive correlation between the protective efficacy and the immunization dose. In conclusion, the different immunization doses of the attenuated and marker M. bovis HB150 and BoHV-1 gG-/tk- combined vaccine were clinically safe in rabbits; the mix of 2.0 × 108 CFU of M. bovis HB150 and 2.0 × 106 TCID50 BoHV-1 gG-/tk- strain was most promising due to its highest humoral and cellular immune responses and a more complete morphology of the lung tissue compared with others. These findings determined the optimal immunization dose of the attenuated and marker M. bovis HB150 and BoHV-1 gG-/tk- combined vaccine, laying a foundation for its clinical application.
摘要：
牛呼吸道疾病（BRD）是养牛业中最常见的疾病之一；它是主要由病毒和细菌共同感染引起的全球流行的多因素感染。在中国,牛支原体（M.牛）和牛疱疹病毒1型（BoHV-1）是与BRD相关的最显着的病原体。我们先前的研究试图将两种疫苗结合起来，并对其最佳抗原比例进行了初步研究。基于这个前提,这项研究通过在兔模型中施用不同剂量的疫苗来确定最有效的免疫剂量，从而扩大了研究范围。免疫接种后,其他免疫剂量组家兔直肠温度正常，无明显临床症状。此外，对从免疫兔收集的样品进行的分析表明，体液和细胞免疫反应增加。此外，肺的组织学分析显示,免疫后的兔比未免疫的兔有更完整的肺组织.此外,保护效力与免疫剂量之间似乎呈正相关。总之,减毒和标记牛分枝杆菌HB150和BoHV-1gG-/tk-联合疫苗的不同免疫剂量在兔中临床上是安全的;2.0×108CFU的牛分枝杆菌HB150和2.0×106TCID50BoHV-1gG-/tk-菌株的混合是最有希望的，因为与其他菌株相比，它具有最高的体液和细胞免疫反应和更完整的肺组织形态。这些发现确定了减毒和标记牛分枝杆菌HB150和BoHV-1gG-/tk-联合疫苗的最佳免疫剂量，为其临床应用奠定基础。
