The advice hub Oral Canker

Canker is a condition mostly associated with pigeons and is caused by a tiny parasite called trichomonas. This parasite is often spread through contaminated drinking water. The parasite causes a ‘yellow button’ of pus to form in your bird’s mouth. This can stop your bird from eating normally leading to weight loss.

What to look for

  • Weight loss
  • Birds picking up food then dropping it
  • A cheese-like plaque in your bird’s mouth (see photo)
  • A reluctance to eat
  • A strong smell


Treating canker or suspected canker is a job for a vet who will likely prescribe an anti-parasitic medication.


Ensure that your birds' drinking water is changed daily and drinkers are cleaned and disinfected regularly. You could use Chicken Vet Poultry Disinfectant for this purpose. Try to keep the drinkers in the chicken house to discourage wild birds from sharing your birds’ water.