Influence of racing on the serum concentrations of acute-phase proteins and bone metabolism biomarkers in racing greyhounds

• We assessed acute phase protein and various metabolites in greyhounds after a 7 km race.
• There were no significant differences between the pre- and post-race serum concentrations of OC and PYD, while the serum concentration of b-ALP increased significantly.
• The serum concentration of CRP decreased significantly but Hp and SAA increased significantly.
• Racing increased serum cortisol, decreased TNF-α and increased vitamin D and testosterone.

This study was designed to evaluate the influence of racing on the serum concentrations of the acute-phase proteins (APPs) C-reactive protein (CRP), haptoglobin (Hp) and serum amyloid A (SAA) in 32 endurance-racing greyhounds. The study also aimed to investigate the effect of a 7 km race on the bone biomarkers osteocalcin (OC), bone-specific alkaline phosphatase (b-ALP) and pyridinoline cross-links (PYD). Total white blood cell (WBC) count, and the serum concentrations of cortisol, tumour necrosis factor-α (TNF-α), vitamin D and testosterone were also determined. Blood samples were collected 24 h prior to (T0) and within 2 h of completion of the race (T1).Compared to baseline values, WBC count did not change significantly (P = 0.2300), serum cortisol, Hp and SAA increased, while TNF-α and CRP decreased (P < 0.0001 for each). There were no significant differences between the pre- and post-race serum concentrations of OC and PYD (P = 0.9500 and P = 0.2600, respectively), but serum b-ALP increased significantly (P = 0.0004). Serum concentrations of vitamin D and testosterone increased after racing (P = 0.0100 and P < 0.0001, respectively). In this study, a 7 km race stimulated an acute-phase response, demonstrated by significant increases in the serum concentrations Hp and SAA in racing greyhounds. Increased serum b-ALP post-race probably indicates a change in bone metabolism and deserves further study.