93 Comparison of physically conditioned and non-conditioned university horses after semester break

Abstract

It is not uncommon for horses to receive breaks from riding that may last as long as several months. During this time of disuse, horses are likely to receive pasture turn-out while not being ridden. This pattern of cyclical work is especially common for horses used in university riding programs. This study aimed to evaluate fitness of physically conditioned and non-conditioned university horses after a semester break, hypothesizing that non-conditioned horses would have a lower level of fitness, resulting in higher resting heart rates and lower levels of muscling, compared with horses remaining in work during the 3-mo period between Spring and Fall semester. Twelve mature stock-type horses aged 16.4 ± 5 yrs at Middle Tennessee State University were divided into 2 groups, a conditioned group that maintained light-to-moderate riding and a non-conditioned group that received no ridden exercise during summer break. Research began at the beginning of the Fall semester and monitored horses for 28 d through their return to work in riding lessons and team practices. On d 0, 14, and 28 peak heart rate during submaximal exercise, resting heart rate, body weight, body condition score, topline muscling score, gaskin circumference, and forearm circumference were recorded. Heart rates were recorded using Polar Equine H10 monitors during rest in stalls and placed under tack while ridden innormal class use of light-to-moderate work. Topline muscling was scored on a previously published scale of 1–5 (1 poor for the breed, 5 exceptional for the breed). Data were analyzed using a mixed model, with effects of day and treatment, with repeated measures (SAS Ver. 9.4). Peak heart rate during submaximal exercise was not different between treatments (P = 0.17) but increased for both treatments through the 28-d study (P = 0.04). The resting heart rate of conditioned horses tended to be lower (P = 0.08). Heart rate results may be influenced by weather, as daily high temperatures decreased from 33°C to 19°C from d 0 to d 28. Forearm circumference was not different (P = 0.30), but gaskin circumference of non-conditioned horses was larger (P = 0.04), although the non-conditioned horses tended to have larger average body weight (P = 0.07). No difference was detected in BCS between groups (P = 0.22). Conditioned horses had higher topline muscling scores (P = 0.02). Compared with their non-conditioned counterparts, horses that were continuously conditioned over a summer semester break had mixed improvement in fitness, based on resting heart rate and topline muscling, suggesting that horses retain a degree of fitness during a 3-mo period of rest on pasture turn-out.