Newcastle disease virus (NDV), a major pathogen of poultry worldwide, causes significant economic losses in the poultry industry. To characterize the ability of recently isolated virulent strains of NDV genotypes VI and VII to cause disease in quails, and to evaluate the efficacy of two NDV vaccines against such strains, Japanese quails were experimentally inoculated with either NDV genotype VI (Pigeon F-VI strain) or VII 1.1 (GHB-328 strain) with or without vaccination with inactivated NDV vaccine of genotype II (La Sota strain) or VII (KBNP strain). Mild to severe neurological signs developed in quails inoculated with the Pigeon F-VI strain from 3 to 14 days post infection (PI) and from 4 to 10 days PI in birds infected with the GHB-328 strain. The mortality rates were 46% and 33% for birds inoculated with NDV VI and NDV VII 1.1, respectively. The severity of histopathological changes depended on the viral isolates used. Vaccination with the La Sota or KBNP vaccine strain successfully protected quails against NDV-induced mortality and decreased the severity of clinical signs, pathological changes and cloacal viral shedding. This study showed that these virulent NDV isolates had mild to moderate pathogenicity in quails and that both vaccines protected against challenge with both virus strains. NDV vaccine genotype VII improved the level of protection against challenge with the VII 1.1 genotype compared with the classic vaccine, but failed to protect quails against challenge with the VI genotype.

新城疫病毒 (NDV) 是世界范围内家禽的主要病原体，给家禽业造成重大经济损失。为了表征最近分离的 NDV 基因型 VI 和 VII 毒株在鹌鹑中引起疾病​​的能力，并评估两种 NDV 疫苗针对此类毒株的功效，日本鹌鹑通过实验接种了 NDV 基因型 VI（Pigeon F-VI 株） ) 或 VII 1.1 (GHB-328 毒株)，有或没有接种基因型 II (La Sota 毒株) 或 VII (KBNP 毒株) 的灭活 NDV 疫苗。在感染后 3 至 14 天 (PI) 和感染 GHB-328 株的鸟类在感染后 4 至 10 天，接种 Pigeon F-VI 株的鹌鹑出现轻度至重度神经系统症状。接种 NDV VI 和 NDV VII 1.1 的鸟类的死亡率分别为 46% 和 33%。组织病理学变化的严重程度取决于所使用的病毒分离株。接种 La Sota 或 KBNP 疫苗株成功地保护了鹌鹑免受 NDV 诱导的死亡，并降低了临床症状、病理变化和泄殖腔病毒脱落的严重程度。该研究表明，这些毒力 NDV 分离株在鹌鹑中具有轻度至中度的致病性，并且两种疫苗均能抵御两种病毒株的攻击。与经典疫苗相比，NDV 基因型 VII 提高了对 VII 1.1 基因型攻击的保护水平，但未能保护鹌鹑免受 VI 基因型攻击。接种 La Sota 或 KBNP 疫苗株成功地保护了鹌鹑免受 NDV 诱导的死亡，并降低了临床症状、病理变化和泄殖腔病毒脱落的严重程度。该研究表明，这些毒力 NDV 分离株在鹌鹑中具有轻度至中度的致病性，并且两种疫苗均能抵御两种病毒株的攻击。与经典疫苗相比，NDV 基因型 VII 提高了对 VII 1.1 基因型攻击的保护水平，但未能保护鹌鹑免受 VI 基因型攻击。接种 La Sota 或 KBNP 疫苗株成功地保护了鹌鹑免受 NDV 诱导的死亡，并降低了临床症状、病理变化和泄殖腔病毒脱落的严重程度。该研究表明，这些毒力 NDV 分离株在鹌鹑中具有轻度至中度的致病性，并且两种疫苗均能抵御两种病毒株的攻击。与经典疫苗相比，NDV 基因型 VII 提高了对 VII 1.1 基因型攻击的保护水平，但未能保护鹌鹑免受 VI 基因型攻击。