AN ALGORITHM TO DESCRIBE THE OXYGEN EQUILIBRIUM CURVE FOR THE THOROUGHBRED RACEHORSE

An algorithm to describe the oxygen equilibrium curve (OEC) of the Tho roughbred horse was derived from raw oxygen equilibrium curve data obt ained under standard conditions of temperature, pH and PCO2 (Smale and Butler, 1994). This algorithm was derived by a curve-fitting procedur e based on the algorithm for human blood produced by Kelman (1966). Th e temperature, fixed acid and net CO2 coefficients were then incorpora ted in the algorithm to enable the accurate calculation of % saturatio n from any combination of PO2, temperature, pH and PCO2. The algorithm was checked using blood gas data obtained from in vivo treadmill exer cise tests as well as a standardised breathing test whereby horses inh aled several different gas mixtures. This algorithm proved more accura te for the Thoroughbred horse than that derived by Kelman.