Medical studies conducted on humans have revealed significant changes in hematological parameters dur-ing sepsis and used these changes for diagnostic and prognostic purposes. However, there are very few studies on the diagnostic and prognostic utility of hematological parameters in the field of veterinary medicine. The objective of this study was to assess whether the parameters mean platelet volume (MPV), erythrocyte distribution width standard devi-ation/coefficient of variation (RDW-SD/CV), platelet distribution width (PDW) and plateletcrit (PCT) hold diagnostic significance in identifying sepsis in calves, while also investigating the interrelationships of these parameters within these sepsis group. The study included 45 calves diagnosed with sepsis and healthy 15 calves as control group. In calves with sepsis, MPV, PCT, RDW-SD, RDW-CV and total leukocyte count were found to be significantly higher than the control group. In their analysis for the diagnosis of sepsis in calves, the sensitivity of MPV was 86.67, the specificity was 84.44, the area under the curve (AUC) was 0.91, and the cut-off point value was 5.95 fL. In addition, the AUC values for other parameters were found as PCT 0.79 (P=0.009), RDW-SD 0.68, RDW-CV 0.75 and WBC 0.80, respec-tively. In the correlation analysis between MPV and other parameters, it was determined that there was a significant relationship between PCT 0.630, PDW 0.310, WBC 0.271, RDW-SD 0.383 and RDW-CV 0.-643. In conclusion, MPV may be a useful biomarker in calves with sepsis due to its favorable diagnostic performance in the early detection of sepsis in new born calves with diarrhea. In order to determine the effects of the results in this study on sepsis very well, it is necessary to work with populations with large sample numbers in the future.

Background: It is unclear whether the increase in BHBA concentration damages the myocardium in ketotic cows. Measurement of troponin is the gold standard in myocardial injury. Objective: The objective of this study was to explore the impact of elevated β‐hydroxybutyrate (BHBA) concentrations on myocardial damage in cows diagnosed with subclinical ketosis (SCK) and clinical ketosis (CK). Additionally, the study aimed to elucidate the relationship between heart‐type fatty acid–binding protein 3 (H‐FABP 3) and high‐sensitivity cardiac troponin I (hs‐cTnI) concentrations, as well as their correlation with various biochemical parameters that assess myocardial and metabolic health. Methods: The animal material used in this study consisted of 30 postpartum Holstein cows, aged between 2 and 5 years. The study group comprised 10 cows with SCK, 10 with CK and 10 cows in the control group (CG). Results: The concentration of hs‐cTnI in cows with CK was significantly higher compared to both the CG ( p < 0.005) and the SCK group ( p < 0.019). Similarly, the H‐FABP 3 concentration in the CK and SCK groups was significantly elevated compared to the CG ( p < 0.001). The creatinine kinase myocardial band (CK‐MB) levels were significantly higher in cows with CK compared to the CG ( p < 0.010). Furthermore, the aspartate aminotransferase (AST) levels in the CK group were significantly elevated compared to the CG ( p < 0.011). A significant positive correlation was observed between BHBA concentration and the levels of both hs‐cTnI and H‐FABP 3 in ketotic cows. Additionally, significant correlations were found between various biochemical parameters (alanine aminotransferase [ALT], AST, CK‐MB and phosphorus) and the concentrations of H‐FABP 3 and hs‐cTnI. Conclusions: This study showed that high BHBA concentrations in ketosis cows may indirectly cause myocardial damage. However, future studies need to investigate the relationship between oxidative stress and changes in antioxidant concentrations and troponin.