Comparison of 2 enzyme immunoassays and a radioimmunoassay for measurement of progesterone concentrations in bovine plasma, skim milk, and whole milk

The objective of this study was to compare 2 enzyme immunoassays (EIAs) with a radioimmunoassay (RIA) as to sensitivity and accuracy in the measurement of the progesterone (P4) concentration in bovine plasma, skim milk, and whole milk. The 72 samples from 24 lactating dairy cows expected to have eit...

Full description

Saved in:
Bibliographic Details
Published in:Canadian journal of veterinary research 2008, Vol.72 (1), p.32-36
Main Authors: Colarzo, M.G, Ambrose, D.J, Kastelic, J.P, Small, J.A
Format: Article
Language:English
Subjects:
accuracy
Animals
blood plasma
Cattle
cows
detection
diestrus
Dietary Fats - pharmacology
direct enzyme immunoassay
enzyme immunoassays
Enzyme-Linked Immunosorbent Assay - methods
Enzyme-Linked Immunosorbent Assay - standards
Enzyme-Linked Immunosorbent Assay - veterinary
Estrous Cycle - blood
Estrous Cycle - metabolism
Female
Lactation - blood
Lactation - metabolism
Milk - chemistry
Pregnancy
Pregnancy, Animal - blood
Pregnancy, Animal - metabolism
progesterone
Progesterone - analysis
Progesterone - blood
Radioimmunoassay - methods
Radioimmunoassay - standards
Radioimmunoassay - veterinary
radioimmunoassays
Reproducibility of Results
Sensitivity and Specificity
skim milk
solid-phase enzyme immunoassay
test sensitivity
whole milk
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The objective of this study was to compare 2 enzyme immunoassays (EIAs) with a radioimmunoassay (RIA) as to sensitivity and accuracy in the measurement of the progesterone (P4) concentration in bovine plasma, skim milk, and whole milk. The 72 samples from 24 lactating dairy cows expected to have either a high P4 concentration (cows in diestrus or pregnant) or a low P4 concentration (cows in estrus or anestrus) were analyzed by RIA, solid-phase EIA (SPEIA), which included a solvent extraction step, or direct EIA (DEIA) without solvent extraction. The overall mean concentrations of P4 did not differ (P < 0.4) among the assays. However, for the cows that were in diestrus or pregnant, the mean P4 concentrations (and standard error) were higher (P < 0.03), regardless of sample type, with RIA than with SPEIA, at 7.3 (0.7) and 6.1 (0.6) ng/mL, respectively. When only the high-P4 samples analyzed by RIA were compared, the mean P4 concentration was higher (P < 0.001) in whole milk than in skim milk, at 9.8 (1.0) and 4.1 (0.7) ng/mL, respectively. Although the mean P4 concentrations in the low-P4 samples did not differ (P < 0.80) among assays, the proportions of cows with a P4 concentration > or = 1 ng/mL were 3%, 14%, and 44% for RIA, SPEIA, and DEIA, respectively (P < 0.01; DEIA > SPEIA > RIA).
ISSN:0830-9000