Iversen Martin H, Eliassen Robert A
Faculty of Biosciences and Aquaculture, University of Nordland, 8049, Bodø, Norway,
Fish Physiol Biochem. 2014 Apr;40(2):527-38. doi: 10.1007/s10695-013-9863-x. Epub 2013 Sep 18.
The experiment consisted of three experimental groups: (1) "vaccine and stress", (2) "stress and vaccine" and (3) control. All groups have previously been vaccinated 6 months prior to the start of the experiment. At the start of the experiment, the "vaccine and stress" group was vaccinated with Pentium Forte Plus for the second time (25.02.2008) and then given a daily stressor (confinement stressor 267 kg m-3 in 15 min) for a period of 4 weeks. The "stress and vaccine" group was given a similar daily stressor for 4 weeks and then vaccinated for the second time. The control group was neither stressed nor vaccinated a second time. The results indicates that fish in the "stress and vaccine" group may have entered an allostatic overload type 2 due to oversensitivity to ACTH, a reduced efficient negative feedback system with elevated baseline levels of plasma cortisol and reduced immune response with pronounced effects on the well-being of the animal. The "vaccine and stress" group may likewise have entered an allostatic overload type 1 response, with oversensitivity to ACTH and transient reduced efficient negative feedback system. This study shows that if plasma cortisol becomes elevated prior to vaccination, it could perhaps instigate an allostatic overload type 2 with dire consequences on animal welfare. To reduce the risk of compromising the animal welfare during commercial vaccination of salmon, one propose to grade the fish minimum a week prior to vaccination or grade simultaneously with vaccination. This could reduce the overall allostatic load during handling and vaccination and secure a healthy fish with intact immune response and improved animal welfare.
（1）“疫苗与应激”组，（2）“应激与疫苗”组，（3）对照组。在实验开始前6个月，所有组均已接种过疫苗。实验开始时，“疫苗与应激”组于2008年2月25日第二次接种奔腾福泰Plus疫苗，然后每天给予应激源（15分钟内267 kg m-3的限制应激源），持续4周。“应激与疫苗”组每天给予类似的应激源，持续4周，然后第二次接种疫苗。对照组既不施加应激，也不进行第二次接种。结果表明，“应激与疫苗”组的鱼可能由于对促肾上腺皮质激素（ACTH）过度敏感、血浆皮质醇基线水平升高导致负反馈系统效率降低以及免疫反应减弱，对动物健康产生显著影响，从而进入了2型适应性负荷过载状态。“疫苗与应激”组同样可能进入了1型适应性负荷过载反应，对ACTH过度敏感，负反馈系统效率暂时降低。这项研究表明，如果在接种疫苗前血浆皮质醇升高，可能会引发2型适应性负荷过载，对动物福利产生严重后果。为了降低在鲑鱼商业疫苗接种过程中损害动物福利的风险，建议在接种疫苗前至少一周对鱼进行分级，或在接种疫苗的同时进行分级。这可以降低处理和接种过程中的总体适应性负荷，确保鱼健康，免疫反应完整，动物福利得到改善。
