Witness Relaxin Canine & Feline Pregnancy (5 Tests)

Write a Review


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.

  • No refrigeration: WITNESS® Relaxin has a 18-months shelf life at room temperature.
  • Fast: reliable results in approximately 10 minutes, so veterinarians can give clients the immediate test results they want, knowing right away whether their dog is pregnant. The WITNESS Relaxin test can detect relaxin as early as day 20 after the luteinizing hormone (LH) surge.
  • Simple-to-understand results need no complex interpretation.
  • Backed by Zoetis Service and Support:
    • Same level of customer support you’re accustomed to receiving
    • Available in 5-test kits


  • Do not use components after expiration date.
  • Refrigeration not required. Store the test kit at 2˚ to 25˚C (35˚ to 77˚F). Do not subject to extreme temperatures.
  • Use the test within 10 minutes after opening the sealed pouch.
  • Avoid touching or damaging membrane at windows 1, 2 or 3.
  • Use a separate pipette for each sample.
  • Hold the pipette and buffer bottle vertically when dispensing sample and buffer.
  • Whole blood cannot be used.
  • For veterinary use only.
View AllClose

Additional Information

View AllClose