WITNESS® Relaxin test identifies the presence of relaxin hormone produced by the developing placenta(s) in the bitch or queen. The WITNESS® format is referred to as Rapid ImmunoMigration (RIM™). This technology is also sometimes referred to as lateral flow or rapid immunochromatography. WITNESS® tests perform well without refrigeration using an antigen-specific antibody labeled with colloidal gold. After the sample and buffer are added to the sample pad (window 1), any antigens in the sample migrate across a nitrocellulose membrane along with the gold-labeled antibody (conjugate) and form an antigen/antibody gold complex. A second antibody specific to the antigen binds the antigen/antibody gold complex at the test line. In a positive sample, this generates a pink to purple colored reaction line in window 2. Excess colloidal gold migrates across to the control line, where an antibody directed to the gold-labeled antibody binds to it. This causes formation of a pink to purple control line (window 3).
A test result should always be interpreted in the context of all available clinical information and history for the dog. Factors such as the breed, size of the bitch, and litter size may influence the level of serum relaxin. Negative results should be retested at least 7 days later. Weak positive results should also be retested 7 days later to confirm pregnancy.
- 5 pouches, each containing 1 test device and desiccant.
- 1 buffer dropper bottle (2ml).
- Instructions for use.
- 5 pipettes.
- Note: Prior to use, test and control bands appear yellow. The bands are dyed yellow for quality control purposes. The dye does not interfere with the test results and will wash away while the test is developing.
1. Do not use components after expiration date.
2. Store the test kit at 2°C-25°C. Do not freeze.
3. Use the test shortly after opening the sealed pouch (within 10 minutes).
4. Avoid touching or damaging membrane at windows (1), (2), (3).
5. The WITNESS device should be placed on a flat, horizontal surface while performing the test.
6. Use a separate pipette for each sample.
7. Hold pipette and buffer bottle vertically when dispensing sample and buffer respectively.
8. For veterinary use only
Canine: Relaxin can be detected in biological samples soon after implantation of the fetilized egg, which occurs about 18 days after LH surge. Relacin is first detectable by WITNESS RELAXIN during the fourth week of pregnancy (from D22 to D28 after ovulation), reaches its highest level in the 6th-8th weeks, and then declines prior to parturition.
Feline: Some pregnancies may be detected as early as 20 days post-mating, while others may not test positive until after 31 days. It is recommended to test after this date if a previous result was negative. Occasionally, positive results may occur in non pregnant queens with elevated relacin levels due to cystic ovaries.
Test Indication: The WITNESS RELAXIN test provides an early, inexpensive and reliable way to determine success or failure of a planned mating or unwanted exposure.
Test Principle: The WITNESS RELAXIN test is a simple test, based on Rapid Immunomigration (RIM) technology, that uses the combination of two anti-relaxin antibodies to quickly detect this hormone in biological samples (serum or plasma) from the bitch and queen. Colloidal gold particles sensitized with an anti-relaxin antibody bind to relaxin molecules present in the sample. The complex is allowed to migrate along a strip and is then capture on a sensitized reaction line (second antibody) where its accumulation causes the formation of a clearly visible pink band. A control band, located at the end of the reading window, ensures that the test was performed correctly.
IMPORTANT: Allow samples and buffer drops to fall onto membrane at window (1). Avoid touching the membrane while applying the sample or buffer drops. Do not touch the membrane with pipette or buffer bottle tips.
However it is not very reliable until around day 37 of the pregnancy. I have tried this on one dog twice (2 separate pregnancies) on day 30 and both were negative 7 days later she was positive.
I also tried tis on a different dog on day 30 thinking it might be just the one dog, but once again I got a false negative.
Its nice to know but it needs to be made to detect the preg just a little sooner. By the time I got a positive result my bitch was only 3 weeks away from delivering.