This study assessed the impact of routine vaccination of Atlantic salmon pre-smolts on gene expression and the possible link to saprolegniosis on Scottish fish farms.

Fish were in 4 different groups 1) ‘control’ – fish without handling or vaccination 2) ‘vaccinated’ - fish undergoing full vaccination procedure 3) ‘non vaccinated’ - fish undergoing full vaccination procedure but not vaccinated and 4) ‘vaccinated-MH’ – fish undergoing vaccination, but procedure involved minimal handling. A strong increase in cortisol and glucose levels was observed after 1 h in all groups relative to the control group. Only in the non-vaccinated group did the level decrease to near control levels by 4 h. Expression levels of six stress marker genes in general for all groups showed down regulation over a 9-day sampling period. In contrast, expression levels for immune response genes in the head kidney showed significant up-regulation for all eight genes tested for both vaccinated groups whereas the non-vaccinated group showed up-regulation for only MHC-II and IL-6b in comparison to the control.

Both the vaccination procedure and the administration of the vaccine itself were factors mediating changes in gene expression consistent with fish being susceptible to natural occurring saprolegniosis following vaccination.

这项研究评估了常规接种大西洋鲑鱼预熏禽对基因表达的影响以及苏格兰养鱼场与腐烂病的可能联系。

鱼分为4个不同的组：1）“对照” –未处理或未进行疫苗接种的鱼2）“已接种疫苗”-接受完全疫苗接种程序的鱼3）“未接种疫苗”-进行了完全疫苗接种程序但未接种疫苗的鱼和4）“已接种MH”的鱼'–鱼正在接受疫苗接种，但程序涉及的处理最少。与对照组相比，所有组在1小时后都观察到皮质醇和葡萄糖水平的强烈增加。仅在未接种疫苗的组中，该水平在4小时内降低至接近对照水平。通常，所有组的六个应激标记基因的表达水平在9天的采样期内均显示出下调。相反，与对照相比，MHC-II和IL -6b。

疫苗接种程序和疫苗本身的使用都是介导基因表达变化的因素，这与鱼类在疫苗接种后容易自然发生腐烂病很敏感。