Abstract
This case report documents the first identified Brucella infection in a 6-year-old male Thoroughbred horse in Libya. The horse exhibited muscle and joint pain, inflammation over the shoulders with a pulpy texture (fistulous withers), stress, fatigue, and potential systemic infection. Its diagnosis was confirmed through serological testing, with agglutination titers of 1/80 for B. melitensis and 1/160 for B. abortus, and a blood culture revealing Gram-negative coccobacilli. After 3 weeks of combination therapy with rifampicin and doxycycline, the inflammation resolved, systemic signs disappeared, the horse's health improved significantly, with restored appetite and reduced levels of stress and fatigue. This novel finding underscores the potential spread of brucellosis across animal species, highlighting brucellosis' spread across animal species and its public health risks. It emphasizes the urgent need for a "One Health" approach, vaccination programs, enhanced diagnostic infrastructure, and international collaboration.