Key Laboratory of Avian Bioproduct Development, Ministry of Agriculture and Rural Affairs, China; Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, China; Institutes of Agricultural Science and Technology Development, College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu 225009, China.
Postgraduate Training Station of Jiangsu Province, Taizhou, Jiangsu 225511, China.
Res Vet Sci. 2020 Feb;128:16-23. doi: 10.1016/j.rvsc.2019.10.005. Epub 2019 Oct 25.
Pseudorabies has caused huge economic losses in China's pig industry and recurred on many large pig farms since late 2011. The disease is caused by highly pathogenic, antigenic variant pseudorabies virus (vPRV) strains. Therefore, the prevention and control of this recurrence of pseudorabies in China has been given priority. In a previous study, we showed that a suitable dose [1 × 10 50% tissue culture infectious dose (TCID) per animal] of commercial Bartha-K61 vaccine protects growing pigs against lethal challenge by the emerging vPRV strain XJ5. In this study, different doses of the Bartha-K61 vaccine and our newly developed rPRV-gI/gE/TK prototype vaccine derived from the vPRV strain XJ5 were used to evaluate immune protection against sublethal challenge by the vPRV strain XJ5. Pigs vaccinated with high doses of the Bartha-K61 vaccine or rPRV-gI/gE/TK prototype vaccine showed no differences in their humoral immune responses, clinical symptoms, body weight gains, viral shedding, or gross and histological lesions after sublethal challenge by the vPRV strain XJ5. Therefore, we concluded that the Bartha-K61 vaccine at a dose of 1 × 10 TCID per animal protects pigs against sublethal challenge by the vPRV strain XJ5 and performs equally well as the same dose of the rPRV-gI/gE/TK vaccine, whereas lower doses of the Bartha-K61 vaccine alone do not protect pigs from this challenge. These findings provide useful information for vaccination interventions and the ultimate eradication of pseudorabies caused by vPRV strains emerging in China.
伪狂犬病在中国的猪产业中造成了巨大的经济损失，并自 2011 年底以来在许多大型养猪场反复出现。该病是由高致病性、抗原变异的伪狂犬病病毒（vPRV）株引起的。因此，预防和控制中国伪狂犬病的再次流行一直是重中之重。在之前的一项研究中，我们表明，合适剂量[每头动物 1×10 50%组织培养感染剂量（TCID）]的商业 Bartha-K61 疫苗可保护生长猪免受新兴 vPRV 株 XJ5 的致死性攻击。在本研究中，使用不同剂量的 Bartha-K61 疫苗和我们新开发的源自 vPRV 株 XJ5 的 rPRV-gI/gE/TK 原型疫苗来评估对 vPRV 株 XJ5 的亚致死性攻击的免疫保护。接种高剂量 Bartha-K61 疫苗或 rPRV-gI/gE/TK 原型疫苗的猪在接受 vPRV 株 XJ5 的亚致死性攻击后，其体液免疫反应、临床症状、体重增加、病毒脱落或大体和组织学病变均无差异。因此，我们得出结论，1×10 TCID 剂量的 Bartha-K61 疫苗可保护猪免受 vPRV 株 XJ5 的亚致死性攻击，其效果与相同剂量的 rPRV-gI/gE/TK 疫苗相当，而单独使用较低剂量的 Bartha-K61 疫苗则不能保护猪免受这种攻击。这些发现为疫苗接种干预和最终根除中国出现的 vPRV 株引起的伪狂犬病提供了有用的信息。
