Evaluation of serum FGF21, ANGPTL4 and PON1 levels in transition period in dairy cows

In this study, it was aimed to determine serum Fibroblast Growth Factor 21 (FGF21), Angiopoietin-like Protein 4 (ANGPTL4) and Paraoxonase 1 (PON1) levels in transition dairy cows and to examine the relationship between body condition score (VKS), non-esterified fatty acids (NEFA) and β-Hydroxybutyric acid (BHBA) levels. The study material consisted of twenty healthy Holstein-Friesian cows three weeks before calving. Blood samples were taken three weeks before calving and at the 1st., 2nd., 4th., 6th. and 8th. weeks after calving after clinical examinations were performed. Simultaneous VKS level was also measured while blood samples were taken. Serum FGF21 and ANGPTL4 levels were measured by ELISA method, and PON1 was measured using a biochemical test kit. As a result of statistical analysis of clinical examination data, no significant difference was found in terms of any parameter. Compared with the prenatal period, a significant increase was observed in serum NEFA, BHBA, FGF21 and ANGPTL4 levels after birth, while a significant decrease was observed in serum PON1 and VKS levels. In the correlation analyzes performed, a positive correlation was observed between NEFA and FGF21 three weeks before birth. A positive correlation was observed between BHBA and FGF21 in the first week after birth, while a negative correlation was determined between FGF21 and PON1. In the second week after birth, there was a negative correlation between BHBA and PON1 and between BHBA and VKS, while a positive correlation was found between FGF21 and ANGPTL4 and between VKS and PON1. As a result, it was determined that NEFA and BHBA levels, which are important metabolites of negative energy balance, as well as hepatokines and PON1 levels in transitional cows changed and there were strong correlations between them. We believe that FGF21, ANGPTL4 and PON1 levels can be markers of metabolic diseases in the evaluation of metabolic profile during the transition period, which is a critical process in dairy farms, and that the data obtained will shed light on future studies and can be used in the field, especially in the diagnosis and prevention of subclinical metabolic diseases.