Indications
Differentiation between bilateral cryptorchidism from previous castration (e.g., rescue).
Confirmation of the presence of testicular tissue when one or both testicles cannot be located during examination or castration.
Notes
Testosterone is secreted by the testicular Leydig cells in a pulsatile way with a diurnal variation (usually lower in the morning). At its lowest, the testosterone concentration of intact dogs and cats can overlap with the concentration of neutered animals, and this is the reason why stimulation protocols used to be suggested (RIG test).
In males, anti-Müllerian hormone (AMH) is produced exclusively by the testicular Sertoli cells. In a few studies, AMH showed to be very sensitive and specific to differentiate intact from neutered male dogs and cats. Some studies showed that cryptorchid dogs appear to have concentrations of AMH even higher than intact males, but the same information is not available for cats.
In cats suspected of being cryptorchids, it is suggested to evaluate their penis for the presence of penile spikes, which are induced by testosterone and disappear about two months after castration or suppression of testosterone production with a deslorelin implant.
To investigate a patient for potential cryptorchidism, it is recommended to start with a single serum sample for either Anti-Müllerian Hormone (AMH) or Testosterone (TEST).
Sampling
- Collect a blood sample (1-2 ml of blood in a plain/gel tube).
- Ensure the sample has clotted and centrifuge the samples 30-120 minutes after collection.
- For samples collected in plain tubes, please separate the serum into another plain tube (this step is not necessary for samples collected in gel tubes).
- Please label the tube with the patient's details and include the patient history, including drug history, on the request form.
- Submit the sample for either Anti-Müllerian Hormone (AMH) or Testosterone (TEST).
