THE EFFECTS OF ENDURANCE EXERCISE ON LIVE ANIMAL PERFORMANCE AND CARCASS GROWTH AND DEVELOPMENT IN SHEEP

Abstract

This study was undertaken to separate the effects of an endurance exercise from normal growth on live animal performance and body composition in growing sheep. To ensure similar exercise intensities among the sheep, training levels were set at 75% of VO 2max . As the length of time on trial increased, pre-exercise resting oxygen consumption decreased significantly (P = 0.008). Exercised sheep consumed more feed but grew at the same rate as their control counterparts. There were no changes in the proportion of muscle, fat or bone as a result of the endurance exercise. However, exercised sheep tended to have a higher proportion of muscle in the proximal pelvic limb (P = 0.02) and in the abdominal wall (P = 0.06). Exercised sheep had a lower proportion of chemically determined intramuscular fat in the semimembranosus after 12 wk and in the vastus lateralis and gastrocnemius after 18 wk of exercise. Key words: Endurance exercise, sheep, body composition, oxygen consumption, muscle distribution