DEA 1 Prevalence and Theoretical Transfusion Mismatch Estimates in Dogs from Southeastern Mexico

Ensuring blood group compatibility is essential in canine transfusion medicine, and Dog Erythrocyte Antigen (DEA) 1 is the most clinically relevant erythrocyte antigen due to its immunogenicity. However, information on its prevalence in Mexico is scarce. This study assessed the distribution of DEA 1 in client-owned dogs from Veracruz–Boca del Río, southeastern Mexico, and applied antigen frequencies to generate theoretical incompatibility scenarios in untyped populations. A cross-sectional study was conducted using blood samples from 192 clinically healthy dogs. DEA 1 typing was performed using a commercial immunochromatographicassay. Frequencies were compared using chi-square or Fisher’s exact test, and 95% confidence intervals were calculated with the Wilson method. Of all dogs sampled, 60.9% (95% CI: 53.6–67.8) were DEA 1-positive. No statistically significant differences were observed by sex or municipality (p > 0.05). Although frequencies varied among breeds, no significant association between breed and DEA 1 status was detected (p > 0.05). Based on observed antigen proportions, mathematical estimations were calculated to illustrate how DEA 1 distribution alone may contribute to potential donor–recipient mismatching when typing is not performed. These estimations are theoretical values and do not represent clinically documented sensitization or transfusion reactions. This study provides the first report of DEA 1 distribution in southeastern Mexico and establishes baseline information that may support future research on canine transfusion practices and donor selection.