Morphological comparison of metapodiums of Holstein and Cemental cattle and age estimation from osteometric indices

In this study, age was estimated using osteometric measurements of metapodium bones from 60 female cattle collected from slaughterhouses in Isparta and the surrounding area. During bone preparation, the bones were cleaned of their soft tissues by soaking them in a 3% hydrogen peroxide solution for 72 hours and then dried at room temperature for 48 hours. Identifying labels were attached to each bone, indicating age group, bone type, and individual number. Measurements were taken with a digital caliper to millimeter precision, repeated three times, and averaged. Osteometric parameters were calculated from standard reference points accepted in the literature. In this study, 20 different osteometric indices were calculated to more accurately assess age-related changes in bones, along with measurements such as bone length, width, and diameter. The aim was to reveal age- specific morphological changes by minimizing the influence of individual differences in absolute dimensions. The findings showed that osteometric measurements exhibited high positive correlations with each other, demonstrating that bone growth and development processes are coordinated and systematic. However, the inverse correlation of some indices with bone length indicated that bones tend to become longer but relatively thinner with age. Comparisons across age groups revealed significant increases in length and diameter measurements of metapodium bones, clearly demonstrating dimensional development, particularly between ages 1 and 5. These results are consistent with previous studies and confirm the dynamics of bone development in cattle. The methodological approach employed in this study—three repeated digital caliper measurements, appropriate laboratory preparation of bones, and calculation of 20 different indices—enhanced the reliability and validity of the data. However, because the study was limited to females, comparisons between sexes were not possible, and this is offered as a recommendation for future research. This study demonstrated that osteometric indices are reliable, practical, and reproducible indicators of age estimation, highlighting their potential for application in veterinary anatomy, zoo archaeology, forensic science, and animal husbandry. Metapodium bones are particularly well- preserved and clearly visible agerelated morphometric changes, making them ideal materials for both archaeological and forensic age determination. Furthermore, the need to consider species and sex in age estimation studies is emphasized, and it is recommended that advanced analyses be supported by radiological and histological methods and that artificial intelligencebased modelling be developed. Osteometric measurements and indices of bovine metapodium bones, which offer a reliable method for age determination, will also provide a solid basis for future research on this topic.