Abstract
A total of 109 heads of horses and ponies from eight horseback riding clubs nearby Central Taiwan were investigated to evaluate the blood parameters and the biochemical compositions of serum for the documentation of clinical pathological diagnosis and exercise physiology. Blood samples were collected from the jugular vein of resting horses. The sex difference in the blood traits were compared both in horses and in ponies. Results shows that total plasma proteins (PP) and hematocrit (PCV) were found higher in male horses than in females (p < 0.05). The sexual effect also exertes a significant influence on the leucocyte (WBC) count, but not on the erythrocyte (RBC) concentration. According to the differential counts of leucocytes, the number of monocytes and lymphocytes was higher in the male pony than that of in male horse. A close relationship Between the erythrocyte sedimention rate (ESR) and the other blood parameters were found especially in PCV, RBC concentration, and plasma protein level. The average ESR observed at 60 minutes were $21.80{\pm}21.87mm$, $39.50{\pm}18.90mm$ and $43.73{\pm}17.89mm$ in stallions, geldings, and mares, respectively. Most of the biochemical components of horse serum detected were distributed in normal ranges, although some of the items show a great variation in such a large sample size.