Hematologic and biochemical changes during canine agility competitions.

BACKGROUND: Normal response to different types of exercise needs to be established before performance, training level, or exercise intolerance can be assessed.
OBJECTIVES: The aim of this research was to describe the hematologic and biochemical changes that dogs undergo during an agility competition.
METHODS: Fifteen dogs were subjected to an agility test that covered a distance of 360-400 m with 40 obstacles. Basal venous blood samples were drawn 1 week before the competition, immediately after exercise, and at 5, 15, and 30 minutes of recuperation. A CBC, plasma biochemical profile, and lactate concentration were determined by standard methods using automated analyzers. Serum cortisol concentration was measured by competitive immune-enzyme analysis; insulin was measured by sandwich ELISA.
RESULTS: Hematologic response to the agility test consisted of significant increases in RBC count, hemoglobin concentration, and HCT, with no change in total protein concentration. Serum triglyceride concentrations were increased postexercise, with highest values observed at 30 minutes of recuperation. Postexercise lactate concentrations exceeded the anaerobic threshold of 4 mmol/L. Serum lactate dehydrogenase activity was significantly higher after 30 minutes of recuperation. Significant differences were not observed in other analytes.
CONCLUSIONS: Our results indicate that agility competitions induce mild to moderate changes in hematologic and biochemical results consistent with splenic contraction, increased lipolysis, and utilization of anaerobic pathways involved in energy resynthesis in muscle.