Comparison of Four Refractometers for the Investigation of the Passive Transfer in Beef Calves
Article first published online: 7 OCT 2011
Copyright © 2011 by the American College of Veterinary Internal Medicine
Journal of Veterinary Internal Medicine
Volume 25, Issue 6, pages 1465–1469, November-December 2011
How to Cite
Vandeputte, S., Detilleux, J. and Rollin, F. (2011), Comparison of Four Refractometers for the Investigation of the Passive Transfer in Beef Calves. Journal of Veterinary Internal Medicine, 25: 1465–1469. doi: 10.1111/j.1939-1676.2011.00816.x
- Issue published online: 16 NOV 2011
- Article first published online: 7 OCT 2011
- Manuscript Accepted: 26 AUG 2011
- Manuscript Revised: 25 FEB 2011
- Manuscript Received: 22 JUN 2010
- Colostral immunity;
- Failure of passive transfer;
- Serum protein
Failure of passive transfer (FPT) in beef calves can be detected by refractometry. Nevertheless, different models of refractometers are available, and few studies compare them for the detection of FPT.
To compare the accuracy of 4 different refractometers for measuring serum total protein concentrations in comparison with results obtained by the biuret method and, based on the serum IgG threshold of 1,600 mg/mL, to determine, for each refractometer, the optimal serum protein concentration's lowest threshold for successful passive transfer.
One hundred and eight healthy beef calves, 3–8 days of age.
Observational study. The concentrations of serum total proteins were determined with 4 different models of refractometers and compared with the biuret method by a Bland–Altman statistical method. The optimal serum protein concentration's lowest threshold for successful passive transfer was determined for each refractometer by receiver operating characteristic (ROC) analysis. In addition, the serum immunoglobulin G (IgG) concentration was compared with the serum gamma-glutamyl transferase (γ-GT) activity and with the total immunoglobulin concentration.
The refractometric measurements were highly correlated with those obtained by the biuret method. Serum total protein concentration threshold values of 56, 58, 54, and 56 g/L were found respectively for the Atago, Atago ATC, Wolf ATC, and digital ATC refractometers. Immunoglobulins were highly correlated with IgG, whereas γ-GT only reflected colostrum uptake by the calf.
Conclusions and clinical importance
All refractometers could be used for the assessment of passive transfer using their individual serum protein concentration threshold.