Evaluation of stress-related parameters and intramural coronary arteriosclerosis in Lidia bulls and Piemontese oxen

The aim of this study was to evaluate how different rearing systems (intensive or semi-extensive) and sexual hormones could affect stress parameters and the development of stress-related intramural coronary arteriosclerosis in Lidia bulls (n = 18) and Piemontese oxen (n = 17). At slaughter, hearts were sampled and submitted to histological investigations in order to evaluate coronary arteriosclerosis. Blood and hair samples were also collected to measure d-ROMS and 20β-dihydrocortisol levels, respectively. No significant differences were recorded for serum levels of d-ROMS between Piemontese oxen and Lidia bulls. On the contrary, Lidia bulls presented higher levels of hair 20β-dihydrocortisol compared to Piemontese oxen (p =.007). Arteriosclerosis was recorded in both the groups. In Lidia bulls, mild to moderate coronary arteriosclerosis was recorded in all the evaluated regions of the heart (right and left papillary muscle; interventricular septum; right and left ventricle free wall; right and left atrium). In Piemontese oxen, mild to severe coronary arteriosclerosis was observed, especially in the left papillary muscle. These results suggest that both cattle breed experienced stress during their rearing cycle. Further studies are needed to clarify the role of housing system and sexual hormones in the development of these subclinical vascular pathology.Highlights Rearing systems can affect animal welfare. Coronary arteriosclerosis, d-ROMS and hair 20β-dihydrocortisol levels can be affected by stress. Lidia bulls and Piemontese oxen experienced different levels of stress during their rearing cycle.