BIRDS · Condition guide
Proventricular dilatation disease in birds: real case reports
Proventricular dilatation disease (PDD) is one of the most feared diseases in companion parrots — a typically fatal disease associated with avian bornavirus (ABV) infection. It causes ganglioneuritis of the autonomic nervous system, most prominently affecting the proventriculus and ventriculus, leading to gastrointestinal dysmotility. Classic signs are chronic weight loss despite a normal appetite, regurgitation, passage of undigested seeds in the droppings, crop stasis, and a distended dilated proventriculus visible on radiographs.
Some birds develop CNS forms instead, with seizures, ataxia, or proprioceptive deficits. Diagnosis combines clinical signs, contrast radiography demonstrating proventricular dilatation, and PCR/serology for avian bornavirus — though many healthy birds also carry the virus, making interpretation complex. Treatment is supportive (easily digestible diet, prokinetics, NSAID anti-inflammatories such as celecoxib in some cases). Most affected birds eventually succumb, though some live with managed disease for years. Strict biosecurity is essential — birds that test positive should not be co-housed with naïve birds.
What vets typically check for
- Contrast radiography (barium) — confirms proventricular dilatation.
- Crop or proventricular biopsy — gold standard but invasive (lymphoplasmacytic ganglioneuritis).
- Cloacal swab PCR + serology for avian bornavirus (interpret with caution — many carriers are healthy).
- Supportive care: easily-digested diet, prokinetics, vitamin supplementation, weight monitoring.
- NSAID therapy (celecoxib) has shown benefit in some cases — discuss with an avian specialist.
Not a replacement for veterinary care. Use this to walk into the conversation prepared, not to self-diagnose.
Real cases from the veterinary literature
Peer-reviewed reports our semantic search surfaces for Proventricular dilatation disease (PDD). Click into any case for the full abstract — or run a personalised search with your pet's exact details.
- Proventricular dilatation disease associated with Avian bornavirus in a scarlet macaw (Ara macao).
Journal of veterinary diagnostic investigation : official publication of the American Association of Veterinary Laboratory Diagnosticians, Inc · 2010 · United States
A scarlet macaw was diagnosed with proventricular dilatation disease, which is a serious condition often linked to a virus called Avian bornavirus. The bird showed signs of being very tired and began pressing its head against objects over a few days. Blood tests showed some abnormalities, but tests for lead, zinc, and certain viruses came back negative. Despite treatment with m
- Avian bornavirus and proventricular dilatation disease: diagnostics, pathology, prevalence, and control.
The veterinary clinics of North America. Exotic animal practice · 2013 · United States
Avian bornavirus (ABV) is a virus that can lead to a condition called proventricular dilatation disease (PDD) in parrots and similar birds. Interestingly, many healthy birds can carry this virus, and it's hard to predict which ones will actually develop PDD. Just because a sick bird tests positive for ABV doesn't mean it has PDD. Research on treatments for this condition is sti
- Proventricular dilatation disease associated with avian bornavirus infection in a Citron-crested Cockatoo that was born and hand-reared in Japan.
The Journal of veterinary medical science · 2011 · Japan
A 5-month-old female Citron-crested Cockatoo, raised in Japan, sadly died from a condition called proventricular dilatation disease (PDD), which affects the bird's digestive system. When the bird was examined, signs of PDD were found, including swelling in the proventriculus (a part of the stomach) and immune cell buildup in various organs and nerves. Tests showed that the bird
- Update on Avian Bornavirus and Proventricular Dilatation Disease: Diagnostics, Pathology, Prevalence, and Control.
The veterinary clinics of North America. Exotic animal practice · 2020 · United States
Avian bornavirus (ABV) is a virus that affects birds and can lead to problems in their stomach and nervous system, a condition known as proventricular dilatation disease (PDD). In affected birds, the virus can cause inflammation in the brain and an enlargement of the proventriculus, which is part of their digestive system. While ABV is found in many birds, both in captivity and
- Proventricular dilatation disease: an emerging exotic disease of parrots in Australia.
Australian veterinary journal · 2007 · Australia
Proventricular dilatation disease is a viral disease seen as a segmental neuropathy in parrots. It has always been believed to be a disease exotic to Australia, with the only reported case being a legally imported Green Wing Macaw (Ara chloroptera) in 1993.
Frequently asked questions
- Is PDD always fatal?
- Currently considered progressive and usually fatal, but some birds live for years with careful supportive management. Early diagnosis, an easy-to-digest diet, and weight monitoring buy the most time and quality of life.
- Can other birds catch it?
- Yes. Avian bornavirus is transmitted between birds (likely via faeces and crop secretions), so infected birds should be isolated from healthy ones. PDD is one of the strongest arguments for quarantine and ABV testing of new arrivals before introduction to a multi-bird household.
- Is it zoonotic?
- Current evidence suggests very low or no risk to humans, but research is ongoing. Standard hygiene (handwashing, no kissing/mouth contact, no shared food) is sensible with any sick bird regardless.