Abstract:
A cohort of Chinook salmon juveniles was vaccinated, with an autogenous bivalent vaccine against New Zealand RLOs (NZ-RLO1) and Tenacibaculum maritimum. A proportion of the cohort was not vaccinated to act as controls. At smoltification, the fish were challenged with NZ-RLO1, NZ-RLO2, or T. maritimum. We found that challenge with T. maritimum by immersion in (7.5 × 105 cfu/mL of water) did not yield any pathology. Challenge with RLOs produced clinical signs that were more or less severe depending on the challenge route, dose or vaccination status. Survival was significantly higher for vaccinated fish within the groups challenged with NZ-RLO1 by intraperitoneal injection with a relative percent survival (RPS) of 48.84%. Survival was not significantly different between vaccinated and non-vaccinated fish for groups challenged with NZ-RLO2 by intraperitoneal injection or by NZ-RLO1 by immersion. Yet, anecdotally the clinical disease presentation (manifesting as haemorrhagic, ulcerative skin lesions) was more severe for the non-vaccinated fish. This study demonstrates that autogenous vaccine against NZ-RLO is protective against severe disease and death by NZ-RLO1 challenge which warrants implementation and further evaluation under field conditions. Yet, this study also highlights the importance of the route of administration and dose when evaluating pathogenicity and vaccine efficacy.
摘要:
一群奇努克鲑鱼幼鱼接种了疫苗,使用针对新西兰RLOs(NZ-RLO1)和海tenacibaculum的自体二价疫苗。组群的一部分没有接种疫苗以作为对照。在糖化时,鱼受到NZ-RLO1,NZ-RLO2或T.maritimum的攻击。我们发现,通过浸入(7.5×105cfu/mL的水)对赤霉病进行攻击不会产生任何病理。RLO的挑战产生了或多或少严重的临床症状,具体取决于挑战途径。剂量或疫苗接种状态。通过腹膜内注射用NZ-RLO1攻击的组中的接种鱼的存活率明显更高,相对存活率(RPS)为48.84%。对于通过腹膜内注射用NZ-RLO2或通过浸泡用NZ-RLO1攻击的组,接种和未接种的鱼的存活率没有显着差异。然而,轶事的临床疾病表现(表现为出血性,溃疡性皮肤病变)对于未接种疫苗的鱼更为严重。这项研究表明,针对NZ-RLO的自体疫苗可预防NZ-RLO1攻击引起的严重疾病和死亡,值得在野外条件下实施和进一步评估。然而,本研究还强调了在评估致病性和疫苗效力时,给药途径和剂量的重要性.