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To date, only a few studies have dealt with the radiological changes of the coffin bone in all equids in terms of roughness of the bone edges, bone resorption as well as remodeling processes and bone deformation. It seems to be an empiric finding that remodeling processes, the associated deformation and new bone formation on the coffin bone are a normal sign of ageing in donkeys. So far, there are no profound studies or publications on corresponding changes in donkeys and their dependence on the age of the animal. The objective of this study is to describe the normal radiographic anatomy of the donkey's coffin bone and to investigate the occurrence of pathological abnormalities, particularly in relation to the age of the animal. Furthermore, the study aims to prove that the changes mentioned above are not a normal sign of ageing in donkeys, but rather pathological conditions, for example as a result of chronic laminitis. Lateromedial radiographs of the distal toe of all limbs of 42 clinically healthy and lameness-free donkeys of European breeds were taken. The occurrence and severity of radiographic changes in the coffin bone were assessed using a scoring system. The tip as well as the extensory processus of the coffin bone were each assessed with regard to the presence of a sharply defined contour. The parietal and sole surfaces were also assessed for the presence of a smooth contour, slight irregularities through to moderate and severe changes and exostoses. The statistical evaluation was carried out with particular attention to the dependence of the changes on the age of the animal. A total of 160 limbs were examined. 28.1% of the coffin bones showed a sharply contoured coffin bone tip, whereas 71.9% showed deviations from the described norm in the sense of a blurred or rounded contour of the coffin bone tip, atrophic and lytic processes in the area of the coffin bone tip or the formation of a cap. The majority of these changes (69.5%) were minor deviations in the sense of a blurred or rounded contour of the coffin bone tip. In the present study, severe changes to the tip of the coffin bone, i.e. atrophy and cap formation, occurred more frequently on the forelimbs than on the hind limbs. The age as well as the weight of the donkeys had a significant influence on the occurrence of changes of the coffin bone tip (p<0.05). While age showed a negative correlation with the changes in the tip of the coffin bone, a positive correlation was found in relation to weight. 10.7% of the coffin bones showed a blurred contour in the area of the extensory processus. With regard to changes in extensory processus no significant correlation with age (p=0.3864) or limb (p=0.0962), but a positive correlation with the weight of the donkeys was found (p<0.05). The parietal surface was smooth in the majority of the cases (65%), 28.1% showed slight roughness of the parietal surface and only 6.9% showed moderate to severe changes, mainly on the front limbs. Age had no significant influence on changes in parietal surface (p=0.2958). However, weight was positively correlated with changes in parietal area and the forelimbs showed significantly more changes than the hindlimbs (p<0.05). In contrast to the parietal surface, the sole surface was sharply contoured in only 28.7% of all cases. The majority (62.5%) showed mild irregularities of the sole surface, moderate changes occurred in 8.8% of the cases and mainly on front limbs. The only parameter that influenced the occurrence of changes in the sole surface significantly was the weight of the specimens, whereas the age (p=0.1712) and the limb (p=0.1432) showed no significant correlation. Overall, almost all (41 of 42 subjects) donkeys showed changes in the coffin bone on at least one limb. The anatomical appearance of the coffin bone of the donkey is similar to that of the horse. Ideally, the tip of the coffin bone should be angular and sharply contoured, whereby a slightly rounded or somewhat unclear contour should not be regarded as pathological. The extensor process should be sharply contoured. The parietal surface should be as smooth as possible, whereas a slightly irregular contour of the sole surface can still be considered normal. In summary, it can be said that radiologically detectable changes in the coffin bone are common even in a clinically healthy donkey population and that, contrary to empirical claims, their occurrence and severity correlate less with the age of the animals and more with their weight. [ABSTRACT FROM AUTHOR]