Evaluation of motilin, ghrelin, and gastrin as potential biomarkers of Type I abomasal ulcers in fattening young bulls.

Abomasal ulcers are frequently observed in slaughtered cattle and can adversely affect animal health and productivity. Motilin, ghrelin, and gastrin are gastrointestinal hormones involved in motility, mucosal integrity, and acid secretion, and may serve as potential biomarkers for gastrointestinal diseases. This study aimed to investigate the relationship between abomasal ulcers, ulcer severity, and serum levels of these hormones, and to evaluate their diagnostic value in fattening cattle. A total of 44 male Holstein cattle aged 16-18 months were clinically evaluated and subsequently slaughtered. Blood samples were collected before transport, and abomasal tissues were examined macroscopically and histopathologically post-mortem. Based on lesion characteristics, animals were classified into three groups: Control (n = 20), mild ulcer [AB(M), n = 15], and severe ulcer [AB(S), n = 9]. All detected ulcers were categorized as Type I following histopathological confirmation. No significant differences in serum motilin, gastrin, or ghrelin levels were observed between the Control and AB(M) groups (P > 0.05). Significantly higher levels (P < 0.001) of motilin, gastrin, and ghrelin were observed in the AB(S) group compared with both the Control and AB(M) groups. No significant differences (P > 0.05) were observed between the Control and AB(M) groups. Moreover, strong positive correlations were observed between all hormone concentrations (r = 0.94-1.00; P < 0.001). ROC analysis indicated that motilin (AUC = 0.781), ghrelin (AUC = 0.781), and gastrin (AUC = 0.829) showed potential for distinguishing cattle with moderate Type I abomasal ulcers from healthy animals, whereas in severe ulcer cases all three markers showed markedly higher diagnostic performance (motilin AUC = 0.878, ghrelin AUC = 0.878, gastrin AUC = 0.956), supporting their use as valuable diagnostic tools, particularly for the identification of severe disease. These findings suggest that serum motilin, gastrin, and ghrelin levels may be useful indicators of abomasal ulcer severity in cattle.