Department of Large Animal Clinical Sciences, Western College of Veterinary Medicine, 52 Campus Drive, Saskatoon, Saskatchewan S7N 5B4 (Erickson, Gow, Lacoste, Waldner); Prairie Diagnostic Service Inc., 52 Campus Drive, Saskatoon, Saskatchewan S7N 5B4 (Godson); Department of Microbiology, Western College of Veterinary Medicine, 52 Campus Drive, Saskatoon, Saskatchewan S7N 5B4 (Ellis).
Can Vet J. 2023 Apr;64(4):321-328.
This study compares immune and clinical responses of bovine viral diarrhea virus (BVDV)-maternal antibody (MatAb)-positive beef calves primed with intranasal modified-live virus vaccine (MLV) and differentially boosted with a systemic MLV or an inactivated vaccine (KV).
Eighteen commercial Black Angus steers.
Calves were mucosally primed at ~24 h of age with an MLV and boosted by injection of a MLV (IN-MLV) or inactivated vaccine (IN-KV) at an average age of 54 d. Challenge occurred at weaning with a virulent non-cytopathic BVDV-2 strain, 24515.
Clinically, the IN-KV group had a longer duration of fever, leukopenia, and viremia, whereas the IN-MLV group had greater BVDV Types-1 and -2 heterospecific antibody responses.
Altogether, these data indicated that systemic MLV boosting resulted in a more robust protection to BVDV Type-2 challenge at weaning.
Mucosal prime-boosting of neonatal calves provided protection against BVDV Type-2 challenge at weaning.
本研究比较了经鼻腔给予改良活病毒疫苗（MLV）进行黏膜初免、并分别采用系统 MLV 或灭活疫苗（KV）进行差异化加强免疫的牛病毒性腹泻病毒（BVDV）-母源抗体（MatAb）阳性肉牛犊的免疫和临床反应。
18 头商业性安格斯公牛犊。
犊牛在约 24 小时龄时经鼻腔给予 MLV 初免，并在平均 54 日龄时通过注射 MLV（IN-MLV）或灭活疫苗（IN-KV）进行加强免疫。在断奶时用一种强毒非细胞病变性 BVDV-2 株 24515 进行攻毒。
临床上，IN-KV 组发热、白细胞减少和病毒血症持续时间更长，而 IN-MLV 组则产生了更强的 BVDV-1 型和 -2 型异源抗体反应。
总的来说，这些数据表明，在断奶时，系统 MLV 加强免疫可对 BVDV-2 型攻毒提供更强大的保护。
对新生犊牛进行黏膜初免-加强免疫可提供针对 BVDV-2 型攻毒的保护。
