Region-specific hematological and biochemical reference intervals for southern Thai fighting bulls

Abstract

Accurate health assessments are vital for the performance and welfare of fighting bulls. Existing hematological and
biochemical reference intervals (RIs) for cattle may not adequately reflect the unique characteristics of fighting bulls
due to breed, age, and geographical differences. This study aimed to develop and apply region-specific RIs for
hematological and biochemical parameters in fighting bulls from southern Thailand. A retrospective analysis of
laboratory records was conducted on 1,460 healthy fighting bulls enrolled in an annual health check program at the
Livestock Animal Hospital, Faculty of Veterinary Sciences, Rajamangala University of Technology Srivijaya, from
January 2016 to December 2023. Blood samples were analyzed for hematological and serum chemistry profiles using
automated analyzers. Statistical evaluations identified significant geographical, seasonal, and age-related variations.
Region-specific RIs were established, revealing slight elevations in red blood cell (RBC) indices, including RBC count,
hemoglobin, hematocrit, mean corpuscular volume (MCV), and mean corpuscular hemoglobin concentrate (MCHC),
as well as serum chemistry parameters such as blood urea nitrogen, creatinine, aspartate aminotransferase (AST),
alkaline phosphatase (ALP), and total protein (TP), compared to previously reported values for other cattle breeds.
Older bulls exhibited lower RBC indices and leukocyte counts (P<0.05), while western coast bulls showed distinct
variations in MCV, leukocyte counts, neutrophils, eosinophils, and ALP compared to eastern counterparts (P<0.05).
Seasonal effects included higher MCHC, monocyte counts, and TP during the rainy season, whereas red cell
distribution width and neutrophil counts increased significantly during summer (P<0.05). These RIs provide valuable
benchmarks for health assessment, disease diagnosis, and physiological monitoring, enhancing the management and
welfare of fighting bulls in southern Thailand.