This study has not been presented at a scientific meeting
Use of Fourier-Transform Infrared Spectroscopy to Quantify Immunoglobulin G Concentrations in Alpaca Serum
Article first published online: 13 JAN 2014
Copyright © 2014 by the American College of Veterinary Internal Medicine
Journal of Veterinary Internal Medicine
Volume 28, Issue 2, pages 639–645, March/April 2014
How to Cite
Burns, J., Hou, S., Riley, C.B., Shaw, R.A., Jewett, N. and McClure, J.T. (2014), Use of Fourier-Transform Infrared Spectroscopy to Quantify Immunoglobulin G Concentrations in Alpaca Serum. Journal of Veterinary Internal Medicine, 28: 639–645. doi: 10.1111/jvim.12258
- Issue published online: 15 MAR 2014
- Article first published online: 13 JAN 2014
- Manuscript Accepted: 23 OCT 2013
- Manuscript Revised: 24 SEP 2013
- Manuscript Received: 6 JUN 2013
- Atlantic Canada Opportunities Agency
- Atlantic Veterinary College Research Fund
- Failure of passive transfer;
- Radial immunodiffusion
Rapid, economical, and quantitative assays for measurement of camelid serum immunoglobulin G (IgG) are limited. In camelids, failure of transfer of maternal immunoglobulins has a reported prevalence of up to 20.5%. An accurate method for quantifying serum IgG concentrations is required.
To develop an infrared spectroscopy-based assay for measurement of alpaca serum IgG and compare its performance to the reference standard radial immunodiffusion (RID) assay.
One hundred and seventy-five privately owned, healthy alpacas.
Eighty-two serum samples were collected as convenience samples during routine herd visits whereas 93 samples were recruited from a separate study. Serum IgG concentrations were determined by RID assays and midinfrared spectra were collected for each sample. Fifty samples were set aside as the test set and the remaining 125 training samples were employed to build a calibration model using partial least squares (PLS) regression with Monte Carlo cross validation to determine the optimum number of PLS factors. The predictive performance of the calibration model was evaluated by the test set.
Correlation coefficients for the IR-based assay were 0.93 and 0.87, respectively, for the entire data set and test set. Sensitivity in the diagnosis of failure of transfer of passive immunity (FTPI) ([IgG] <1,000 mg/dL) was 71.4% and specificity was 100% for the IR-based method (test set) as gauged relative to the RID reference method assay.
Conclusions and Clinical Importance
This study indicated that infrared spectroscopy, in combination with chemometrics, is an effective method for measurement of IgG in alpaca serum.