Akköse Mehmet, Kaya Ufuk, Yazlik Murat Onur, Göcen Murat, Vural Mehmet Rıfat
Department of Livestock, Dalaman Agricultural Enterprise, General Directorate of Agricultural Enterprises, Muğla, Türkiye.
Department of Biostatistics, Faculty of Veterinary Medicine, Hatay Mustafa Kemal University, Antakya, Türkiye.
Vet Med Sci. 2025 Sep;11(5):e70592. doi: 10.1002/vms3.70592.
Hyperketonaemia is a common problem in periparturient sheep. This study aimed to evaluate the performance of FreeStyle Optium Neo H (FS) for measuring blood β-hydroxybutyric acid (BHBA) concentrations in sheep. Whole-blood BHBA concentrations were measured using the FS from the jugular and ear veins of 175 clinically healthy, late-gestation (n = 56) and postparturient (n = 119) ewes. Jugular blood serum samples were also used for the reference sampling site. Blood BHBA concentrations measured with the FS from the jugular and ear veins showed a high positive correlation with the serum concentrations measured using the reference method (r = 0.84, r = 0.81, respectively). According to the Bland-Altman plot and limits of agreement, when compared to the reference method, FS recorded lower BHBA concentrations of 0.03 and 0.04 mmol/L from the jugular and ear veins, respectively. Passing-Bablok regression analysis revealed an intercept of -0.125 (95% CI: -0.148 to -0.078) and a slope of 1.250 (95% CI: 1.111-1.304) for the jugular vein and an intercept of -0.005 (95% CI: -0.089 to -0.018) and a slope of 1.000 (95% CI: 0.909-1.111) for the ear vein. The receiver operating characteristics (ROC) analysis determined that the optimal thresholds of the FS for the jugular and ear veins were, respectively, ≥0.8 mmol/L (sensitivity, 87.5%; specificity, 97.6%, AUC, 0.896) and ≥0.6 mmol/L (sensitivity, 87.5%; specificity, 91.0%, AUC, 0.887) for the identification of sheep with pregnancy toxaemia (PT). In conclusion, although there was constant and proportional errors indicating non-agreement with the reference method in the Passing-Bablok regression equation, FS's diagnostic performance was good enough to identify ewes with PT or hyperketonaemia.
高酮血症是围产期绵羊常见的问题。本研究旨在评估FreeStyle Optium Neo H（FS）血糖仪在测量绵羊血液β-羟基丁酸（BHBA）浓度方面的性能。使用FS血糖仪从175只临床健康的妊娠后期（n = 56）和产后（n = 119）母羊的颈静脉和耳静脉测量全血BHBA浓度。颈静脉血清样本也用作参考采样部位。用FS血糖仪从颈静脉和耳静脉测量的血液BHBA浓度与用参考方法测量的血清浓度呈高度正相关（分别为r = 0.84和r = 0.81）。根据Bland-Altman图和一致性界限，与参考方法相比，FS记录的颈静脉和耳静脉BHBA浓度分别低0.03和0.04 mmol/L。Passing-Bablok回归分析显示，颈静脉的截距为-0.125（95%CI：-0.148至-0.078），斜率为1.250（95%CI：1.111 - 1.304）；耳静脉的截距为-0.005（95%CI：-0.089至-0.018），斜率为1.000（95%CI：0.909 - 1.111）。受试者工作特征（ROC）分析确定，FS血糖仪用于颈静脉和耳静脉识别妊娠毒血症（PT）绵羊的最佳阈值分别为≥0.8 mmol/L（敏感性，87.5%；特异性，97.6%，AUC，0.896）和≥0.6 mmol/L（敏感性，87.5%；特异性，91.0%，AUC，0.887）。总之，尽管在Passing-Bablok回归方程中存在恒定和比例误差，表明与参考方法不一致，但FS血糖仪的诊断性能足以识别患有PT或高酮血症的母羊。
