Serum Paraoxonase as an Indicator for Fatty Liver in Sheep

Abstract

Introduction: A model of fatty liver in postpartum sheep was established to measure blood paraoxonase 1 (PON1) and other biochemical indicators, which were used to predict fatty liver in sheep.

Material and methods: Sheep were assigned into two experimental groups: a fatty liver group (T, n = 10) and a healthy control group (C, n = 5). PON1 enzyme activity towards paraoxon as a substrate was quantified spectrophotometrically. The results were analysed by t-test and pearson correlation coefficient. Disease was predicted by binary logistic analysis, and diagnostic thresholds were determined by receiver operatingcharacteristic (ROC) analysis.

Results: The activity of serum PON1 in group T was significantly decreased (P < 0.05) when compared with C group, and liver lipid content and the levels of serum BHBA, NEFA, and TG were significantly increased (P < 0.05). Thresholds were lower than 74.0 U/mL for PON1, higher than 0.97 mmol/L for β-hydroxybutyrate, higher than 1.29 mmol/L for non-esterified fatty acids, higher than 0.24 mmol/L for triglycerides, and lower than 71.35 g/L for total protein.

Conclusion: This study verified that PON1, BHBA, NEFA, TG, and TP could be used to predict the risk of fatty liver in sheep.

Keywords: biochemical indices; fatty liver; paraoxonase 1; sheep.

Fig. 1

Receiver operating characteristic (ROC) plots for PON1 activity, BHBA, NEFA, TG and TP for diagnosis of ketosis in sheep (PON1: paraoxonase-1; BHBA: hydroxybutyric acid; NEFA: non-esterified fatty acids; TG: triglyceride; TP: total protein). The NEFA line and the TG line coincide together, and part of the BHBA line coincides with the TG line