Thresholds of whole-blood β-hydroxybutyrate and glucose concentrations measured with an electronic hand-held device to identify ovine hyperketonemia.
Metabolic disorders, especially hyperketonemia, are very common in dairy sheep. The whole-blood concentrations of β-hydroxybutyrate (BHBA) and glucose can be determined by commercially available electronic hand-held devices, which are used in human medicine and for the detection of ketosis in dairy cows. The aim of this study was to evaluate the suitability of the hand-held device Precision Xceed (PX; Abbott Diabetes Care Inc., Abbott Park, IL) to detect hyperketonemia in ewes. An additional objective of this study was to evaluate the agreement between samples obtained by minimal invasive venipuncture of an ear vein and measurements of whole-blood samples from the jugular vein (vena jugularis, v. jug.). Blood samples taken from the v. jug. were collected from 358 ewes on 4 different farms. These samples and a blood drop obtained from an ear vein were analyzed simultaneously on farm with the PX. For method comparison, the samples obtained from the v. jug. were also analyzed by standard methods, which served as the gold standard at the Central Laboratory of the University of Veterinary Medicine Vienna, Austria. The correlation coefficients between the serum BHBA concentration and the concentrations measured with the hand-held meter in the whole blood from an ear vein and the v. jug. were 0.94 and 0.96, respectively. The correlation coefficients of plasma and whole-blood glucose concentration were 0.68 for the v. jug. and 0.47 for the ear vein. The mean glucose concentration was significantly lower in animals classified as hyperketonemic (BHBA ≥ 1.6 mmol/L) compared with healthy ewes. Whole-blood concentrations of BHBA and glucose measured with the PX from v. jug. showed a constant negative bias of 0.15 mmol/L and 8.4 mg/dL, respectively. Hence, a receiver operating characteristic analysis was performed to determine thresholds for the PX to detect hyperketonemia in ewes. This resulted in thresholds for moderate ketosis of BHBA concentrations of 0.7 mmol/L in blood from an ear vein and the v. jug. Cutoffs of 1.0 mmol/L (ear vein) and 1.1 mmol/L (v. jug.) BHBA were determined to detect animals at greater risk to develop severe hyperketonemia. Applying these thresholds, excellent test characteristics, with sensitivities of 1.00 for both samples and specificities of 0.98 for the ear vein and 0.97 for the v. jug. were determined. These results demonstrate that the PX is a useful tool for detection of hyperketonemia in ewes.
Clinical Unit for Herd Health Management for Ruminants, University Clinic for Ruminants, Department for Farm Animals and Veterinary Public Health, University of Veterinary Medicine Vienna, 1210 Vienna, Austria.
M
M
Pichler
Clinical Unit for Herd Health Management for Ruminants, University Clinic for Ruminants, Department for Farm Animals and Veterinary Public Health, University of Veterinary Medicine Vienna, 1210 Vienna, Austria.
A
A
Damberger
Central Clinical Pathology Unit, Department for Pathobiology, University of Veterinary Medicine Vienna, 1210 Vienna, Austria.
I
I
Schwendenwein
Agricultural Research and Education Center Raumberg-Gumpenstein, 8952 Irdning (Styria), Austria.
J
J
Gasteiner
Clinical Unit for Herd Health Management for Ruminants, University Clinic for Ruminants, Department for Farm Animals and Veterinary Public Health, University of Veterinary Medicine Vienna, 1210 Vienna, Austria.
M
M
Drillich
Clinical Unit for Herd Health Management for Ruminants, University Clinic for Ruminants, Department for Farm Animals and Veterinary Public Health, University of Veterinary Medicine Vienna, 1210 Vienna, Austria. Electronic address: Michael.Iwersen@vetmeduni.ac.at.
M
M
Iwersen
D020155:3-Hydroxybutyric Acid / Q000097:blood*; D000818:Animals; D001317:Austria; D001774:Blood Chemical Analysis / Q000379:methods* / Q000662:veterinary; D001786:Blood Glucose / Q000378:metabolism*; D001800:Blood Specimen Collection / Q000379:methods; D005260:Female; D007662:Ketosis / Q000097:blood* / Q000175:diagnosis* / Q000662:veterinary*; D012372:ROC Curve; D012680:Sensitivity and Specificity; D012756:Sheep; D012757:Sheep Diseases / Q000097:blood / Q000175:diagnosis
D001786:Blood Glucose; D020155:3-Hydroxybutyric Acid
hand-held meter; ketosis; pregnancy toxemia; β-hydroxybutyrate