Combinatorial effects of administration of immunostimulatory compounds in feed and follow-up administration of triple-dose SLICE® (emamectin benzoate) on Atlantic salmon, Salmo salar L., infection with Lepeophtheirus salmonis

摘要: Several immunostimulatory feed additives have shown the ability to induce protective responses in Atlantic salmon infection with Lepeophtheirus salmonis. However, even most encouraging results rarely surpass a 50% index host. That fact coupled well-documented limitations of single-therapy strategies effective management parasitic infections generally make it imperative identify therapies that can be combined an integrated pest approach for sea lice. With this mind, we hypothesized feeds could enhance protection provided by SLICE® emamectin benzoate (EMB). To test hypothesis, were fed one two different (CpG ODN or Aquate®) c. 7 weeks, challenged L. salmonis copepodids early within period and then placed on triple-dose (150 μg kg(-1) ) 1 week following completion feeding period. CpG (2 mg commercial yeast extract (Aquate® 0.2%) inclusion able successfully inflammatory gene expression (interleukin-1β) head kidneys infected fish at 13 26 days post-exposure (DPE), DPE, respectively. Lice burdens lower (18%) Aquate® (19%) diets; however, due variability, these not statistically significant over time. Despite no reductions lice numbers, 33 DPE had significantly reduced cortisol levels when compared control diet. Cortisol receiving diet from initial baseline prior infection, whereas elevated all other time points. positive effects feeds, synergism was observed follow-up treatment . In fact, highest survival immunostimulation.