Field Evaluation of Liver Ultrasound Measurements and Biochemical and Metabolic Parameters During the Transition Period in Dairy Cows

Ketosis and fatty liver syndrome are metabolic disorders apparent in dairy cows during the transition period. The study focused on examining how varying levels of milk production in dairy cows might reflect or influence specific blood biochemical markers and liver health as assessed through ultrasonography. A total of 65 Holstein-Friesian cows from six farms were evaluated at three time points as follows: 7 days before expected calving and at 7 and 21 +/- 3 days postpartum. Each evaluation included the body condition score (BCS), blood sampling for biochemical analysis, and liver ultrasonography. Based on average farm milk yield, cows were divided into three production groups as follows: GR1 (38.4 +/- 6.45 L/day, n = 23), GR2 (42.9 +/- 2.77 L/day, n = 24), and GR3 (45.69 +/- 7.49 L/day, n = 18). Parameters assessed included liver lipid content and ultrasonographic measurements such as portal vein diameter and depth, liver depth, and liver angle. Significant time-dependent changes were observed in liver size, fat metabolism, and electrolyte balance, especially postpartum. However, no significant differences emerged among the production groups, indicating that these changes likely represent physiological adaptations to lactation. These findings support the use of blood analysis and ultrasonography as practical, minimally invasive tools for routine metabolic health monitoring in dairy cows during the transition period.