{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,23]],"date-time":"2026-09-23T05:17:22Z","timestamp":1790140642045,"version":"4.0.1"},"reference-count":55,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2021,11,29]],"date-time":"2021-11-29T00:00:00Z","timestamp":1638144000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Animals"],"abstract":"<jats:p>Within the lay literature, and social media in particular, there is often debate about the age at which a horse should be started and introduced to racing or sport. To optimize the welfare and longevity of horses in racing and sport, it is important to match exercise with musculoskeletal development and the ability of the musculoskeletal system to respond to loading. The justification for not exercising horses at a certain age is often in contrast to the scientific literature and framed, with incorrect generalizations, with human growth. This review provides a relative comparison of the growth and development of the horse to the descriptors used to define growth and development in humans. Measures of physeal closure and somatic growth demonstrate that the horse completes the equivalent of rapid infant growth by weaning (4\u20136 months old). At approximately 11 months old, the horse completes the equivalent of the childhood phase of growth and enters puberty. At 2 years old, the horse has achieved most measures of maturity used within the human literature, including the plateauing of vertical height, closure of growth plates, and adult ratios of back length:wither height and limb length:wither height. These data support the hypothesis that the horse evolved to be a precocious cursorial grazer and is capable of athletic activity, and use in sport, relatively early in life.<\/jats:p>","DOI":"10.3390\/ani11123402","type":"journal-article","created":{"date-parts":[[2021,11,29]],"date-time":"2021-11-29T22:50:45Z","timestamp":1638226245000},"page":"3402","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":41,"title":["Growth and Bone Development in the Horse: When Is a Horse Skeletally Mature?"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4253-1825","authenticated-orcid":false,"given":"Chris W.","family":"Rogers","sequence":"first","affiliation":[{"name":"School of Veterinary Science, Massey University, Private Bag 11-222, Palmerston North 4442, New Zealand"},{"name":"School of Agriculture and Environment, Massey University, Private Bag 11-222, Palmerston North 4442, New Zealand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5218-6589","authenticated-orcid":false,"given":"Erica K.","family":"Gee","sequence":"additional","affiliation":[{"name":"School of Veterinary Science, Massey University, Private Bag 11-222, Palmerston North 4442, New Zealand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1813-2197","authenticated-orcid":false,"given":"Keren E.","family":"Dittmer","sequence":"additional","affiliation":[{"name":"School of Veterinary Science, Massey University, Private Bag 11-222, Palmerston North 4442, New Zealand"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,11,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2069","DOI":"10.1071\/AN17685","article-title":"Equine musculoskeletal development and performance: Impact of the production system and early training","volume":"60","author":"Rogers","year":"2020","journal-title":"Anim. 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