Markers of iron metabolism in retired racing Greyhounds with and without osteosarcoma

BackgroundGreyhounds have well‐described clinicopathologic idiosyncrasies, including a high prevalence of osteosarcoma (OSA). Hematocrit, HGB, and HGB oxygen affinity are higher than in other dogs, while haptoglobin concentration is lower, so we hypothesized that Greyhounds have a different iron metabolism. To our knowledge, there are no reports on serum iron profiles in Greyhounds.ObjectivesTo elucidate iron metabolism in Greyhounds, we wanted to compare serum iron concentration, total iron‐binding capacity (TIBC), and percent transferrin saturation (%SAT) in healthy retired racing Greyhounds (RRGs) with OSA (RRGs –OSA), and also with non‐Greyhounds (NGs), without and withOSA(NGs –OSA).MethodsSerum iron concentration and unsaturated iron‐binding capacity (UIBC) were measured by standard methods, andTIBCand %SATwere calculated inRRGs (n = 25),RRGs –OSA(n = 28),NGs (n = 30), andNGs –OSA(n = 32).ResultsTIBCwas lower inRRGs than inNGs (P < .0001), and inRRGs –OSAthan inNGs –OSA(P < .0001).NGs –OSAhad lowerTIBCthan healthyNGs (P = .003). PercentSATwas higher inRRGs than inNGs (P < .0001) and inRRGs –OSA(P = .008), and %SATwas also lower inNGs than inNGs –OSA(P = .004). PercentSATwas also higher inRRGs –OSAthan inNGs –OSA(P = .001). BothRRGs –OSA(P = .02) andNGs –OSA(P < .0001) had lower serum iron concentrations than their healthy counterparts.ConclusionLowerTIBCand higher %SATmay constitute another Greyhound idiosyncrasy compared with other dogs. In this study, all dogs withOSAhad higher serum iron concentrations and %SATthan healthy dogs.