This test is valid for samples taken between 35 and 120 days after breeding.

Purpose of Test:
To test for pregnancy in horses based on the level of PMSG (eCG)

Description of Test and Procedures:
The test is a radioimmunoassay performed with in-house reagents.  The radioimmunoassay technique is based on the competitive binding of the serum and a radiolabeled hormone preparation.  They compete for binding to an antibody specific for the hormone being tested.  The antibody-bound radiolabeled hormone is separated and the quantity is determined by counting on a gamma spectrometer.

Sample Needed and Procedures for Submittal:
Submit at least 1 mL of serum on a cold pack.

Schedule For Running Test:
The assay is set up Thursday and results are reported Monday afternoon.  STAT assays may be set up Monday-Thursday and results are reported the following day.

Interpretation of Results:
Results are reported as YES, NO or INCONCLUSIVE (MAYBE) based on the relative level of PMSG (eCG) present in the sample.  A pregnant mare may test negative if the sample was taken too early (PMSG has not risen yet) or too late (PMSG has already declined).  Results for the unknown are read by comparing them to serum of a known pregnant mare at two different dilutions.  If a sample drawn between 35-40 days post-breeding and result is reported NOT PREGNANT, it is advised to re-check in 1-2 weeks as in very few mares, production of hCG may have been delayed.

Please note:  This is not a quantitative assay.  Therefore there are no normal values.