Physiological responses of mules on prolonged exposure to high altitude (3 650 m)

Hematological changes and athletic performance in horses in response to high altitude (3,800 m)

“…Horses can store up to 50% of their red cell volumes (RCV) in the spleen (25), and release of all of these cells requires a substantial stress (such as high-intensity exercise). Lack of control animals and exercise also limits the amount of hematologic data that can be obtained from studies on mules at altitude (27). The present study was designed to expand our understanding of the physiological processes involved with acclimatization to high altitude in the horse.…”

Selected echocardiographic parameters and right sided pressures of the mule

“…Although there are anecdotal references to mules having an innate ability to withstand higher workloads and having greater endurance than horses (Travis 1990), there are few physiological studies that substantiate these statements. This perceived ability is also noted at high altitude settings where mules serve in packing and military operations (Riar et al 1976(Riar et al , 1982Travis 1990); however, controlled studies are few.…”

Environmental stress and 3‐day eventing: effects of altitude

“…Increased altitude is a poorly studied environmental stressor for 3-day event horses. Previous experiments have described the effects of high altitude on horses (DeAluja et al 1968;Collins et al 1969;Wickler et al 1995) and mules (Riar et al 1976(Riar et al , 1980Wickler et al 1995;Greene et al 1996) performing packing work or show jumping, but we are unaware of previous reports on the effects of altitude on 3-day eventing. This experiment was undertaken with the hypothesis that increased altitude would have measurable physiological effects on horses competing in 3day events and horse trials when compared to horses competing in similar tests at sea level.…”