Assessment of insulin sensitivity and blood pepsinogen values in dairy herds with high risk for displaced abomasum.

This study evaluated insulin sensitivity and serum pepsinogen in dairy cows from herds with high and low risk for displaced abomasum (DA) across different lactation stages. Blood samples and body condition scores (BCS) were collected from 235 clinically healthy cows on five farms in Hokkaido, Japan, including two high-DA farms (≥4%) and three DA-free farms. Cows from high-DA farms consistently exhibited lower values of the revised quantitative insulin sensitivity check index and quantitative insulin sensitivity check index, along with higher values of homeostatic model assessment, indicating reduced insulin sensitivity. These cows also had higher BCS and elevated circulating insulin concentrations, particularly during the dry period and late lactation. In contrast, serum pepsinogen values remained within the normal range and did not differ significantly between groups, suggesting no apparent abomasal mucosal damage. These findings indicate that cows in the high-DA farms experience a prolonged negative energy balance from early lactation to mid lactation, which may contribute to persistent insulin resistance and increased susceptibility to DA. The results may highlight the importance of metabolic management, rather than abomasal pathogenesis, in preventing DA in high-risk farms.