** AWARDS ISSUED PRIOR TO JANUARY 20, 2025, WERE FUNDED UNDER PREVIOUS ADMINISTRATIONS AND MAY NOT REFLECT THE PRIORITIES AND POLICIES OF THE CURRENT ADMINISTRATION.** ALTERNATIVE APPROACHES TO REDUCE ANTIBIOTIC USE ON DAIRY FARMS ARE NEEDED TO ADDRESS INDUSTRY AND CONSUMER CONCERNS. BLANKET DRY COW THERAP, OR INTRAMAMMARY INFUSION OF HIGH CONCENTRATION AND LONG-LASTING ANTIBIOTICS INTO EVERY QUARTER TO PREVENT INTRAMAMMARY INFECTION AT MILKING CESSATION, ACCOUNTS FOR A LARGE PORTION OF THE ANTIBIOTIC USAGE ON DAIRY FARMS. THUS, PRACTICES THAT REDUCE INTRAMAMMARY INFECTION AND SIMULTANEOUSLY DECREASE ANTIBIOTIC USAGE ARE CRITICALLY NEEDED. OUR OVERALL OBJECTIVES ARE TO 1) DETERMINE THE EFFECT OF ALTERATIVE DRY-OFF MANAGEMENT PRACTICES ON STRESS, INFLAMMATION, IMMUNITY, AND INTRAMAMMARY INFECTION OCCURRENCE OF DAIRY COWS IN ORDER TO REPLACE BLANKET DRY COW THERAPY ON DAIRY HERDS, AND 2) DEVELOP AN EXTENSION PROGRAM TO SHARE THE CURRENT KNOWLEDGE IN MASTITIS CONTROL, JUDICIOUS ANTIBIOTIC USAGE AND RESEARCH FINDINGS WITH DAIRY PRODUCERS, VETERINARIANS, AND INDUSTRY PRACTITIONERS. WE HYPOTHESIZE THAT LESS FREQUENT MILKING AND ADMINISTRATING DRY COW VACCINES PRIOR TO DRY-OFF WILL MINIMIZE STRESS AND INFLAMMATION, IMPROVE IMMUNITY AND PREVENT INTRAMAMMARY INFECTION, AND PROVE VIABLE ALTERNATIVES FOR BLANKET DRY COW THERAPY. WE WILL PERFORM TWO APPLIED RESEARCH PROJECTS IN MULTIPLE DAIRY FARMS TO TEST OUR HYPOTHESIS, AND BUILD A ROBUST EXTENSION PROGRAM FOCUSING ON EDUCATING DAIRY PRODUCERS, VETERINARIANS, AND INDUSTRY PRACTITIONERS FOR JUDICIOUS ANTIBIOTIC USAGE BY ADOPTING MANAGEMENT PRACTICES THAT IMPROVE MAMMARY HEALTH WITH LESS RELIANCE ON ANTIBIOTICS. THESE INTEGRATED EFFORTS WILL EVENTUALLY IMPROVE NOT ONLY THE HEALTH AND WELFARE OF DAIRY CATTLE, BUT ALSO PROFITABILITY OF DAIRY PRODUCERS AND SUSTAINABILITY OF DAIRY FARMS.