Evaluation of a lateral-flow immunoassay for use in monitoring passive transfer of immunoglobulins in calves.
OBJECTIVE
To determine the predictive ability of a commercially available lateral-flow immunoassay used for determining passive transfer of immunoglobulins in calves.


METHODS
204 male Holstein calves ranging from 4 to 8 days old.


METHODS
Serum samples were obtained from each calf. Results of refractometry, zinc sulfate turbidity technique, and the lateral-flow immunoassay were determined. Sensitivity, specificity, accuracy, and predictive ability were calculated on the basis of IgG concentrations determined by turbidimetric immunoassay (TIA).


RESULTS
Mean IgG concentration in the study was 10.9 mg/ml as determined by TIA. Rate of failure of passive transfer in this study population was 56%. Associations between the values for the refractometry and zinc sulfate turbidity techniques were established by regression analysis. Accuracy for the lateral-flow immunoassay, refractometry, and zinc sulfate turbidity methods was 95, 80, and 73%, respectively.


CONCLUSIONS
The lateral-flow immunoassay was better at determining the status of passive transfer of immunoglobulins, compared with the refractometry or zinc sulfate turbidity methods. The ability of the lateral-flow immunoassay to provide accurate results should enable clinicians to make immediate management or intervention decisions.
Mcvicker
Jerry K
JK
Midland BioProducts Corp, Boone, IA 50036,USA.
Rouse
Glenda C
GC
Fowler
Mike A
MA
Perry
Bruce H
BH
Miller
Bill L
BL
Johnson
Thomas E
TE
D000818:Animals; D002417:Cattle / Q000276:immunology*; D007116:Immunization, Passive / Q000662:veterinary*; D007118:Immunoassay / Q000379:methods / Q000662:veterinary*; D007074:Immunoglobulin G / Q000032:analysis*; D008297:Male; D009391:Nephelometry and Turbidimetry / Q000662:veterinary; D011933:Reagent Kits, Diagnostic / Q000662:veterinary; D012031:Refractometry / Q000662:veterinary; D012680:Sensitivity and Specificity; D019287:Zinc Sulfate
D007074:Immunoglobulin G; D011933:Reagent Kits, Diagnostic; D019287:Zinc Sulfate