Acute phase protein concentrations in retired racing Greyhounds

Retired racing Greyhounds are popular as pets. Greyhounds have several differences in physiological values compared with other breeds, including lower serum alpha- and beta-globulin concentrations. We hypothesized that lower acute phase protein (APP) concentrations could contribute to lower alpha- and beta-globulin concentrations in this breed. The purpose of this study was to compare serum concentrations of several APPs in Greyhounds with those of other dog breeds. We measured the serum concentrations of C-reactive protein (CRP), haptoglobin (Hp), acid-soluble glycoprotein (ASG), ceruloplasmin (CP), and serum amyloid A (SAA) in 15 clinically healthy retired racing Greyhounds and 11 age- and gender-matched healthy nonGreyhound controls using previously validated methods. Results were compared by Student's t-tests. The concentration of Hp by both colorimetric and immunoturbidimetric methods was significantly lower in Greyhounds than in nonGreyhound dogs (P=.0009 and .019, respectively). The concentration of ASG was also significantly (P=.007) lower in Greyhounds, but CRP and CP concentrations were not significantly different between groups. SAA concentration was below the detection limit of the method in all dogs. The low serum concentrations of Hp and ASG should be taken into consideration when interpreting APP results in Greyhounds. Because both Hp and some ASG migrate in the alpha-globulin fraction, these results may explain the low alpha-globulin concentrations in Greyhounds.