کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5799456 | 1555238 | 2011 | 7 صفحه PDF | دانلود رایگان |
Exercise or lack of it in early life affects chondro-osseous development. Two groups of horses were used to investigate the effects of age and exercise regimen on bone parameters of diaphyseal, metaphyseal, epiphyseal and cuboidal bones of the distal limb of Thoroughbreds. One group had exercised only spontaneously from an early age at pasture (PASTEX group), while the other group of horses were exposed to a 30% greater workload through additional defined exercise (CONDEX). Longitudinal data from peripheral quantitative computed tomography (pQCT) were obtained from eight scan sites of the left forelimb (proximal phalangeal (Pp; 1 site), third metacarpal (Mc3; six sites) and third carpal (C3; one site) bones) of 32 Thoroughbred foals scanned five times from â¼3Â weeks to 17Â months of age. The primary outcome measures were bone mineral content (BMC), bone area (BA), and periosteal circumference (Peri C) in diaphyseal bone, with cortical thickness (CortTh), volumetric bone mineral density (BMDv) and a bone strength index (SSI) also being analysed.At the Pp site within the model there was a significant effect (PÂ =Â 0.00-0.025) of conditioning exercise increasing bone parameters, except endosteal circumference (Endo C) and BMDv. The BMC, BA, and SSI of Pp were significantly greater in the CONDEX than PASTEX groups at 12 and 17Â months (PÂ =Â 0.015-0.042) and CortTh at 17Â months (PÂ =Â 0.033). At the M55 site of Mc3 BMC, BA and SSI (PÂ =Â 0.02-0.04), and at the M33 site, SSI (PÂ =Â 0.05) were higher in the CONDEX than PASTEX group. The adaptive responses, consistent with diaphyseal strengthening, were more marked in the diaphysis of Pp than Mc3. In the Mc3, metaphysis, trabecular BMDv was less in the CONDEX than PASTEX group, associated with greater bone mineral accretion in the outer cortical-sub-cortical bone in the CONDEX group. There were no significant between-group differences in any epiphyseal or cuboidal bone parameter. Although the early imposed exercise regimen was not intensive, it had significant effects on diaphyseal bone strength, through change in size but not bone density.
Journal: The Veterinary Journal - Volume 190, Issue 3, December 2011, Pages 383-389