Institute of Biodiversity, Animal Health and Comparative Medicine, College of Medicine, Veterinary and Life Sciences, Glasgow University, Glasgow, Scotland, UK.
Poult Sci. 2018 Feb 1;97(2):463-469. doi: 10.3382/ps/pex340.
Vaccination is an important tool in poultry health, but is itself a stressor often resulting in a reduction in feed intake, body weight gain, and nutrient digestibility. In other species, vaccination is associated with an immediate acute-phase response. As an important immune parameter, the circulating heterophil/lymphocyte (H/L) ratio is a well-recognized parameter of stress in poultry. In this study, the effects of a routinely used commercial poultry vaccine on the acute phase response (APR) and H/L ratios in specific pathogen-free (SPF) layer chicks was examined to determine if post vaccination (PV) stress and an APR occur. A combined Newcastle disease and infectious bronchitis vaccine (Nobalis Ma5+Clone 30) was administered to SPF chicks by the intraocular route at age 7 d. Acute phase proteins (APP), alpha-1 acid glycoprotein (AGP) and serum amyloid A (SAA) were measured by enzyme-linked immunosorbent assays at d 0 (pre-vaccination) and d 0.5, 1, 2, 3, 4, 5, 6, and 21 PV. Stress was determined in the chicks by measurement of the H/L ratio. The immune response to the vaccine was estimated by measurement of the antibody (IgY) response to the vaccine at d 21.The antibody titer was significantly (P < 0.05) higher in the vaccinated group at 21 d PV, confirming stimulation of the immune system. The H/L ratio was also significantly higher in the vaccinated group at 1 to 2 d (P < 0.01) and at 3 d (P < 0.05) PV. The concentration of SAA increased by 2.8-fold, from 63.7 μg/mL in controls to 181 μg/mL in the vaccinated group, (P < 0.05) at 1 d PV. AGP increased 1.6-fold at 2 d PV, (from 0.75 g/mL in the control group to 1.24 g/mL in the vaccinated group, P < 0.05).In conclusion an immediate but mild APR occurred in the chicks following intraocular vaccination, whereas the stress response as measured by H/L ratio seemed to be more specific and sensitive. Measurement of these biomarkers of the host response could be a tool in vaccine development.
疫苗接种是家禽健康的重要工具，但本身也是一种应激源，常导致采食量、体重增加和养分消化率降低。在其他物种中，疫苗接种与即刻的急性期反应（acute-phase response，APR）有关。作为一个重要的免疫参数，循环嗜中性粒细胞/淋巴细胞（heterophil/lymphocyte，H/L）比值是家禽应激的公认参数。在这项研究中，检查了常规使用的商业家禽疫苗对特定病原体无特定病原（specific pathogen free，SPF）层鸡雏的急性期反应（APR）和 H/L 比值的影响，以确定接种疫苗后（post vaccination，PV）是否存在应激和 APR。通过眼内途径在 7 日龄时给 SPF 鸡雏施用组合的新城疫和传染性支气管炎疫苗（Nobalis Ma5+Clone 30）。通过酶联免疫吸附测定法在 d0（接种前）和 d0.5、1、2、3、4、5、6 和 21PV 时测量急性期蛋白（acute phase protein，APP）、α-1 酸性糖蛋白（alpha-1 acid glycoprotein，AGP）和血清淀粉样蛋白 A（serum amyloid A，SAA）。通过测量 H/L 比值来确定鸡雏的应激情况。通过测量 21dPV 时疫苗的抗体（IgY）反应来估计疫苗的免疫反应。抗体滴度在 21dPV 时在接种组中显著（P < 0.05）更高，证实了免疫系统的刺激。在接种组中，H/L 比值在 1 至 2d（P < 0.01）和 3d（P < 0.05）PV 时也显著升高。SAA 的浓度增加了 2.8 倍，从对照组的 63.7μg/mL 增加到接种组的 181μg/mL（P < 0.05）在 1dPV 时。AGP 在 2dPV 时增加了 1.6 倍，（从对照组的 0.75g/mL 增加到接种组的 1.24g/mL，P < 0.05）。总之，鸡雏眼内接种后立即出现轻度 APR，但 H/L 比值测量的应激反应似乎更特异和敏感。宿主反应这些生物标志物的测量可能是疫苗开发的一种工具。
