** AWARDS ISSUED PRIOR TO JANUARY 20, 2025, WERE FUNDED UNDER PREVIOUS ADMINISTRATIONS AND MAY NOT REFLECT THE PRIORITIES AND POLICIES OF THE CURRENT ADMINISTRATION.** VACCINATION IS THE MOST EFFECTIVE WAY TO PREVENT INFECTIOUS DISEASE OUTBREAKS IN AQUACULTURE. LONG-TERM DURATION OF VACCINE PROTECTION OFTEN REQUIRES SEVERAL VACCINES DOSES, HOWEVER, WE DO NOT UNDERSTAND HOW THE INTERVAL BETWEEN PRIME AND BOOST VACCINES IMPACTS THE DURATION AND QUALITY OF THE IMMUNE RESPONSES ELICITED BY THESE VACCINES. THIS PROJECT WILL USE CUTTING-EDGE IMMUNOLOGICAL METHODS AND LEVERAGE NEW FINDINGS IN THE FIELD OF FISH MUCOSAL IMMUNITY TO FILL IMPORTANT KNOWLEDGE GAPS IN THE FIELD OF TROUTVACCINOLOGY WITH THE GOAL OF IMPROVING THE SUSTAINABILITY OF THE AQUACULTURE INDUSTRY IN THE US.