Figure 1.

Overview of experimental design. Following 7 weeks of feeding trial, fish fed both diets were subjected to immune challenge by an intraperitoneal (IP) injection of sterile phosphate-buffered saline (PBS), bacterial antigen Aeromonas salmonicida (ASAL), or viral mimic polyriboinosinic polyribocytidylic acid (pIC). mirVana-prepared head kidney (HK) templates from three of each PBS-, pIC-, and ASAL-injected fish (control diet only) were selected for deep sequencing based on the qPCR assessed expression of known pIC (i.e., isg15a, mxb, irf7b) and ASAL (i.e., campb, tlr5a, il1b) immune biomarker transcripts. Selected pIC- and/or ASAL-responsive miRNAs were studied by qPCR using all samples from both dietary groups. *mRNA qPCR analyses were conducted using DNase-treated and column-purified total RNA.