AbstractThis study investigated the growth promoting effects of yeast extract (YH) fed to Sprague‐Dawley male rats (3 weeks old) for 4 weeks. The negative (N)‐control and positive (P)‐control groups were given a daily oral administration of saline and foremilk (1 g/kg of BW), respectively, and the YH‐1 and YH‐2 groups were given daily administrations of YH (0.5 and 1 g/kg of BW, respectively). After 4 weeks, the YH‐1, YH‐2 and P‐control groups showed significant differences in the body weight gain compared with the N‐control group (p < 0.05). The YH‐1 and YH‐2 groups also had significantly different tibial bone growths (0.47 and 0.49 mm/day, respectively) and femur bone growths (0.52 and 0.53 mm/day, respectively) compared with the N‐control group (0.37 mm/day of tibial growth and 0.42 mm/day of femur growth) (p < 0.05). The YH‐1 and YH‐2 groups had significantly different growth plate (proximal epiphysis) height increments (0.62 and 0.56 mm, respectively) compared with the N‐control group (0.17 mm) (p < 0.05). Lastly, the YH‐1 and YH‐2 groups presented different growth hormone (GH) levels (1.77 and 2.10 ng/mL, respectively) than the N‐control group (0.82 ng/mL) (p < 0.05). YH administration increased longitudinal bone growth and GH secretion in rats. Consequently, YH may offer an improved ability to treat GH deficiency‐related disorders. Copyright © 2008 John Wiley & Sons, Ltd.
