Impact of feeding and housing on the development of osteochondrosis in foals—A longitudinal study

•This study focused on the evolution of OC related to the environment during the period from 6 months (after weaning) till 18 months.•Horses not presenting OCD during the first months of life and fed with concentrates had a trend to develop osteochondrosis lesions.•Horses positive to OCD at the first examination (6 months) and fed without concentrates (paddock, or just hay or roughage) had higher probabilities of recovering than those fed with concentrates.•Environment conditions may define the evolution of osteochondrosis. Osteochondrosis dissecans (OCD) is a developmental orthopedic disease caused by a failure of the endochondral ossification in epiphyseal plates and joint cartilage. This trouble may induce the presence of osteochondral fragments in the articulation, fissures or subchondral bone cysts in the growth cartilage. Occurrence of osteochondrosis is influenced by a complex interaction of different factors. Among these, the effect of the housing and the feeding of the foals during their first months of life, have been described as risk factors for the development of osteochondrosis. The aim of this study was to investigate the evolution of OCD lesions with a longitudinal study in 204 young foals from 6 to 18 months in comparison to the type of feeding and the type of housing conditions. These factors and OCD status were obtained by a questionnaire and radiological examination, respectively. This allowed dividing the foals into four groups according to the initial OCD status and the evolution of the condition. As a result, we found that foals fed with concentrates show a higher probability to develop OCD lesions (p=0.06), while foals not receiving concentrates, had a higher probability to heal from existing OCD lesions (p=0.001). This study supports the theory that management factors such as feeding or housing may influence the evolution of the osteochondrosis disease.