Roh J-H, Kang M, Wei B, Yoon R-H, Seo H-S, Bahng J-Y, Kwon J-T, Cha S-Y, Jang H-K
Departments of Infectious Diseases and Avian Diseases, College of Veterinary Medicine and Korea Zoonosis Research Institute, Chonbuk National University.
Department of Broiler Breeder, Halim Co. LTD, South Korea.
Poult Sci. 2016 May;95(5):1020-4. doi: 10.3382/ps/pew042. Epub 2016 Mar 4.
The production performance, efficacy, and safety of two types of vaccines for infectious bursal disease virus (IBDV) were compared with in-ovo vaccination of Cobb 500 broiler chickens for gross and microscopic examination of the bursa of Fabricius, bursa/body weight (b/B) ratio, flow cytometry, and serologic response to Newcastle disease virus (NDV) vaccination. One vaccine was a recombinant HVT-IBD vector vaccine (HVT as for herpesvirus of turkeys) and the other was an intermediate plus live IBDV vaccine. A significant difference was detected at 21 d. Eight of 10 chickens that received the IBDV live vaccine had severe bursal lesions and a relatively low b/B ratio of 0.95, and an inhibited NDV vaccine response. On the other hand, the HVT-IBD vector vaccine resulted in mild bursal lesions and a b/B ratio of 1.89. Therefore, the live vaccine had lower safety than that of the HVT-IBD vector vaccine. To determine the protective efficacy, chickens were intraocularly challenged at 24 d. Eight of 10 chickens in the IBDV live vaccination group showed gross and histological lesions characterized by hemorrhage, cyst formation, lymphocytic depletion, and a decreased b/B ratio. In contrast, the HVT-IBD vector vaccinated chickens showed mild gross and histological lesions in three of 10 chickens with a b/B ratio of 1.36, which was similar to that of the unchallenged controls. Vaccinated chickens showed a significant increase in IBDV antibody titers, regardless of the type of vaccine used. In addition, significantly better broiler flock performance was observed with the HVT-IBD vector vaccine compared to that of the live vaccine. Our results revealed that the HVT-IBD vector vaccine could be used as an alternative vaccine to increase efficacy, and to have an improved safety profile compared with the IBDV live vaccine using in-ovo vaccination against the Korean very virulent IBDV in commercial broiler chickens.
通过对Cobb 500肉鸡进行蛋内接种传染性法氏囊病病毒（IBDV）疫苗，比较了两种IBDV疫苗的生产性能、效力和安全性，对法氏囊进行大体和显微镜检查、计算法氏囊/体重（b/B）比值、进行流式细胞术检测以及检测对新城疫病毒（NDV）疫苗接种的血清学反应。一种疫苗是重组火鸡疱疹病毒-IBD载体疫苗（HVT为火鸡疱疹病毒），另一种是中等毒力加活IBDV疫苗。在21日龄时检测到显著差异。接受IBDV活疫苗的10只鸡中有8只出现严重的法氏囊病变，b/B比值相对较低，为0.95，并且对NDV疫苗的反应受到抑制。另一方面，HVT-IBD载体疫苗导致法氏囊病变较轻，b/B比值为1.89。因此，活疫苗的安全性低于HVT-IBD载体疫苗。为了确定保护效力，在24日龄时对鸡进行眼内攻毒。IBDV活疫苗接种组的10只鸡中有8只出现以出血、囊肿形成、淋巴细胞耗竭和b/B比值降低为特征的大体和组织学病变。相比之下，HVT-IBD载体疫苗接种的鸡在10只中有3只出现轻度大体和组织学病变，b/B比值为1.36，与未攻毒对照组相似。无论使用何种疫苗类型，接种疫苗的鸡的IBDV抗体滴度均显著升高。此外，与活疫苗相比，使用HVT-IBD载体疫苗观察到肉鸡群的生产性能显著更好。我们的结果表明，HVT-IBD载体疫苗可作为一种替代疫苗，以提高效力，并与在商品肉鸡中使用蛋内接种针对韩国超强毒IBDV的IBDV活疫苗相比，具有更好的安全性。
