Trichomoniasis (canker) in budgies is a protozoal infection of the upper digestive tract caused by Trichomonas gallinae, producing cheesy yellow-white masses in the mouth, throat, and crop that interfere with eating and breathing. It is highly contagious between birds and requires prompt antiprotozoal treatment.
Last reviewed: June 2026
What Is Budgie Trichomoniasis (Canker)?
Trichomoniasis — commonly called "canker" in birds — is caused by the flagellated protozoan Trichomonas gallinae, which colonizes the upper gastrointestinal tract from the mouth and crop through to the esophagus. The organism is transmitted through direct contact with infected saliva, contaminated water, shared food dishes, or crop-to-crop feeding between birds. As described in Carpenter's Exotic Animal Formulary, trichomoniasis is one of the most common infectious diseases in budgerigars (parakeets), and flock outbreaks can be devastating. Stress, poor husbandry, and concurrent illness increase susceptibility. Birds can carry the organism without visible signs and then develop active disease when their immune defenses are compromised.
Recognizing the Signs of Canker in Budgies
The most distinctive sign of trichomoniasis is the appearance of caseous (cheese-like) yellow or white plaques inside the mouth or at the back of the throat. However, many birds show digestive and behavioral signs before the plaques become obvious.
Classic signs:
- Cheesy or caseous masses in the mouth, throat, or at the corner of the beak — yellow-white, irregular, and adherent (unlike food residue, they do not wipe away easily)
- Regurgitation or vomiting — the bird may bob its head and bring up undigested food or mucus
- Difficulty swallowing — the bird pecks at food but cannot get it down, or drops food repeatedly
- Crop distension — the crop may feel swollen, doughy, or fail to empty normally
- Bad breath or a foul odor from the mouth
Secondary and systemic signs:
- Progressive weight loss despite appearing to try to eat
- Lethargy and fluffed feathers — the bird sits at the bottom of the cage or on a low perch
- Labored breathing if masses extend into the trachea or nasal passages
- Wet or stained feathers around the face and beak from regurgitation
Any budgie with yellow-white material in the mouth that does not wipe away, or that is regurgitating repeatedly, should be seen by an avian vet promptly (AAV Basic Care for Companion Birds, 2019).
Diagnosis and Treatment
Diagnosis: A wet mount smear of material from the mouth or crop — examined under a microscope — directly reveals the motile Trichomonas organisms. Crop wash or a crop swab can also be examined. The organisms are highly characteristic: pear-shaped with rapidly-moving flagella. Diagnosis is usually straightforward for an avian vet with access to a microscope.
Treatment:
- Metronidazole or ronidazole are the drugs of choice in budgies; treatment typically runs 5–10 days and is highly effective when initiated early
- All birds in contact with the affected bird must be treated simultaneously
- Disinfecting shared water dishes, food bowls, and cage surfaces with appropriate agents kills the organism, which does not survive long outside a host
Supportive care — hand-feeding, crop support, and warmth — is needed for birds that are not eating adequately on their own. As described in Carpenter's Exotic Animal Formulary, early treatment carries an excellent prognosis; severe cases with large masses or tracheal involvement are more guarded.
When to See a Vet
Call your vet today if:
- You see any yellow or white material inside your budgie's mouth or at the base of the beak that does not rub off
- Your budgie is regurgitating or vomiting repeatedly, not just occasional normal regurgitation to a mate
- Your budgie is losing weight or refusing to eat over more than a day or two
- Your budgie's crop is distended and does not empty normally overnight
- Another bird in the household has been diagnosed with trichomoniasis and your budgie may have had contact
Go to the ER immediately if:
- Your budgie is breathing with its mouth open, tail-bobbing, or gasping
- Your budgie has collapsed to the cage floor and is not responding normally
- Your budgie cannot swallow and is showing signs of obstruction
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Frequently Asked Questions
What does canker look like in a budgie's mouth? Canker appears as irregular yellow-white or cream-colored plaques or masses inside the mouth, at the back of the throat, or at the corner of the beak. Unlike food residue, these masses are firmly adherent and do not wipe away with a cotton swab. In severe cases the masses are large and visibly block the throat. The odor from the mouth may also be noticeably foul.
Is budgie trichomoniasis contagious to other birds or humans? Trichomoniasis is highly contagious between birds through shared water, saliva, and crop feeding — so all birds in contact with an infected bird should be tested and treated. The organism is specific to birds and does not infect humans or other mammals, so there is no zoonotic risk to owners handling an infected budgie with normal hygiene.
How long does canker treatment take in budgies? Metronidazole or ronidazole treatment typically lasts 5–10 days. Most birds show improvement within the first few days of treatment — reduced regurgitation, increased appetite, and the plaques beginning to resolve. A follow-up crop smear after treatment confirms clearance. Some birds need a second course if the infection is not fully eliminated.
How much does treating trichomoniasis in a budgie cost? An avian vet consultation typically runs $75–150, and the diagnostic crop smear adds $50–100. Medication for a course of treatment costs $20–60. Total costs for a straightforward case are generally $150–300. Avian vet workups overall run $300–700 when diagnostics and supportive care are included. All in-contact birds needing treatment will add to total costs.
Can canker be prevented in budgies? Quarantine all new birds for 30 days before introducing them to existing birds, and have any new bird examined by an avian vet. Use separate food and water dishes between birds where possible, and disinfect dishes regularly. Avoid overcrowding, which increases transmission risk and immunosuppression from stress.
Still Not Sure if Your Budgie Needs a Vet?
When you're not sure if this is wait-and-see or call-tonight, Voyage AI Vet triages in under 2 minutes. Describe what you're seeing in chat, share photos of your budgie's beak, mouth, or throat — or any visible masses — or hop on a live video call if you want a second pair of eyes. Every answer comes with citations to the actual veterinary literature it's pulling from — so you see exactly where the guidance comes from, not just a chatbot's word.