The Spleen as a Target to Characterize Immunomodulatory Effects of Down-Stream Processed Cyberlindnera jadinii Yeasts in Atlantic Salmon Exposed to a Dietary Soybean Meal Challenge

In this experiment, we used four diets, one based on FM, a challenging diet with 40% soybean meal (SBM), and two diets containing 40% SBM with 5% of Cyberlindnera jadinii yeast exposed to different down-stream processing conditions (heat-inactivated or autolysation). The immunomodulatory effects of the diets were analyzed in the spleen of Atlantic salmon after 37 days of feeding. The results showed that the inclusion of autolysed C. jadinii (ACJ) was able to modulate the response of Atlantic salmon compared to fish fed the SBM-diet, through the activation of biological pathways related to endocytosis, PPRs-signal transduction and transporter activity. Finally, we suggest that the spleen is a good candidate to characterize the immunomodulatory effects of functional ingredients in Atlantic salmon. Spleen mRNA profiles from Atlantic salmon after 37 days fed different functional diets. Grants: .Foods of Norway a Centre for Research-based Innovation (237841/030), Research Council of Norway .Trained immunity and nutritional programming for resilient salmon (RCN 294821), Research Council of Norway