Enzyme-linked Immunosorbent Assay Progesterone Test Kit


What is an ELISA Test?

An ELISA test, an Enzyme-linked Immunosorbent Assay is a biochemical technique used mainly in immunology to detect the presence of an antibody or an antigen in a sample. We use it for progesterone testing so that we can determine the level of progesterone in a sample of plasma or serum.

Why use ELISA Kit?

By confirming the progesterone level in plasma or serum we show exactly at what stage  in the oestrus cycle a particular animal is.  This can aid correctly times insemination, early pregnancy indication and can give information on the presence and type of ovarian cysts.

For the vets it can be used as a quantitative aid alongside normal scanning and palpation to give more complete picture.  It can also be used as an aid to help diagnose cystic ovaries as whether it is a follicular or luteal cyst.

How does ELISA Kit work?

Each progesterone ELISA test kit uses a 96 microplate coated with an antibody with high specificity for progesterone.  Samples of serum/plasma are added to each well along with an enzyme conjugate label. This is then left to incubate for an hour before washing the plate and adding a substrate.  The substrate reaction produces a colour change which is inversely proportional to the amount of progesterone in the sample. Strong colour means Low progesterone.

Plasma/serum plate quantitatively measures (giving numerical values) progesterone in plasma or serum samples. The kit is designed for use in the laboratory setting.  Each set of samples is run alongside a set of standard which are of predetermined concentration which produces a standard curve when read with an absorbance plate reader. This allows a simple program to calculate accurate values for the amount of progesterone in each samples.


Standards are created using plasma or serum from anoestrus or ovariectomised animal in which there will be little or negligible amount of progesterone. Standards are species specific. Different species have slightly different blood composition and since certain compounds can inhibit the binding of progesterone standards samples must be like for like.

Progesterone is added respectively in known volumes to create a set of known concentration standards.

The Standard curve is designed to show the greatest colour distinction between 1-4 ng/ml Progesterone. The plate should run with a full set of standards (0, 0.5, 1,2, 5, 10, 20ng/ml) enabling a quantitative analysis to be run. Samples should be stored (-10—36 degree C) ensure through mixing after thawing.

Two Camels

Use of progesterone Eliza kit in camels is mainly for improving reproductive management. P4 ELIZA kits are used for early detection of pregnancy 13-14 days after natural mating or AI.  In Embryo Transfer, P4 kits are used in recipients one day before transfer to ensure there is  active CL present with good output of progesterone and also 10 days post embryo transfer for detection of early pregnancy.

We can supply standards made from camel plasma upon request should you require species specific standard.

Use of progesterone ELIZA kits in dairy industry goes back to more than 40 years ago.  The initial objective was to identify cows coming to heat a couple days before showing sign of heat, and not to miss them being inseminated.  At first, this service was offered by Milk Marketing Board   then private companies made kits that could be used on the farms.

It revolutionised the industry at that time especially since the use of scanners were limited.  Still it is a valuable tool to identify and monitor  resumption of cyclicity, identifying returned cows before showing the signs of heat, study of level of embryonic mortality by the farmer  before alerting the vet.

It is also possible to use milk or plasma ELIZA kits depending on the availability of facilities to the farmer or to the vets.

Fantastic tool to reduce your calving interval and make your farm more profitable.

Use of progesterone ELIZA kits in sheep industry is less common compared to the extend it is used in Dairy industry.

For research purposes progesterone ELIZA kits are used to measure the release of progesterone from vaginal devices like DICO or  CIDR, containing natural progesterone using Ovariectomised ewes.