Normal distribution of immunoglobulin isotypes in adult horses

Studies focusing on the equine humoral response are scarce, with a bias towards the pre- and post-parturition mare and its foal. The present study attempted to expand current knowledge by establishing normal ranges for adult horse serum isotypes. Immunoglobulin (Ig) concentrations were obtained by screening 47 horses of various breeds and in different training regimes. Radial immunodiffusion values (mg/dL) were 196 ± 73 for IgA, 2704 ± 1424 for IgG, 419 ± 220 for IgG(T) and 70 ± 30 for IgM. All values passed the Kolmogorov–Smirnov normality test. The results will be of use to the field veterinarian as well for the basic researcher working on horses.