Budgies can be prone to species-specific diseases and ailments. Among the most concerning is polyomavirus – colloquially referred to as French molt (as the virus was discovered in budgies imported from France) or budgerigar fledgling disease (as it impacts young birds.)
A budgie living with French molt will lose an excessive number of feathers at a young age, typically before it reaches 6 weeks old. This is irregular, as most budgies molt for the first time at around 16 weeks. The feathers around the wings and tail will be most affected.
The consequences of French molt can be severe, especially if a diagnosis of polyomavirus isn’t made early. In most cases, the budgie will be rendered permanently incapable of flight. The condition can also be fatal, so suspicious molting patterns should be investigated.
Protein deficiency, stressful and crowded living conditions, inbreeding, and mite infestations are all suggested as causes of French molt. As it’s highly contagious, young budgies must be protected and housed appropriately in a hygienic environment.
Unfortunately, there’s no cure for French molt. Budgies can live if the condition is captured in good time, but they need special care. Polyomavirus survivors are often called “crawlers” or “runners” as they can’t fly and must live alone to prevent spreading the infection.
What Is Avian Polyomavirus?
Avian polyomavirus is a viral infection impacting members of the Psittacidae family of birds.
Polyomavirus is a form of papovavirus, the group of viruses commonly associated with skin complaints such as warts, lesions, skin tags, and tumors.
In the case of avian polyomavirus, it manifests as unusual molting patterns. One of the nicknames for polyomavirus is budgie fledgling disease because it impacts young birds. Any budgie can carry polyomavirus, but it usually lies dormant in adults.
The infection is commonly referred to as French molt because it was initially discovered in Germany among budgies imported from France. Many budgies died, and the survivors lost almost all the feathers around their wings and tails at 6 weeks old.
According to Virology, this disease negatively affects the internal organs of budgies, which means that it’s often fatal in young budgies. Even if your budgie survives, it’ll be unable to fly.
Symptoms of French Molt in Budgies
The primary symptom of French molt is the shedding of feathers around the wings and tail.
The first feathers to fall will come from the center of the wings, and the remainder of the feathers rhythmically fall from the budgie’s wings.
The feathers are lost symmetrically from each wing, but it’s not an aesthetic process.
If you look closely, you’ll see dried blood on the skin where the feathers have dropped because they were still growing when they fell. You’ll not notice any other skin complaints, but the keratin coating of the dropped feathers will feel weak and insubstantial
You may notice other symptoms if your budgie has French molt, including:
- Refusal to eat or hydrate
- Bruised or reddened skin around the wings, potentially leading to open sores.
- Swelling in the abdomen
Unfortunately, many additional symptoms are generic and could point to other concerns.
What Causes French Molt in Budgies?
Polyomavirus can be hereditary, so breeders are advised not to mate budgies that survive French molt, but this advice isn’t always heeded. Equally, as French molt symptoms are often dormant in adult budgies, an unwitting carrier may be chosen for breeding.
The potential causes for a budgie to develop French molt independently are many and varied but remain speculative at the time of writing. No avian expert has identified the reason for French molt in young budgies.
Stress is a potential trigger, especially when young budgies are forced to live in crowded cages with excessive conspecifics. Budgies love company, but they also need space.
An unbalanced diet, most notably protein deficiency, is a risk. The same applies to a shortage of methionine, an amino acid commonly found in seeds, Brazil nuts, and dark leafy greens.
What causes French molt is almost less concerning than what happens when a solitary case arises. It only takes one budgie to develop the virus and spread it to a flock, simultaneously putting others at risk.
The blame for widespread French molt outbreaks is often placed on unsanitary living conditions. The virus can be spread orally, so two bonded birds will likely share an infection. These budgies will spend most of their time nearby, sharing space and food.
More often, the disease is spread through inhalation of urine and feces in a shared bird cage. If a habitat isn’t regularly cleaned and maintained, the risk of viral infection drastically increases.
Is French Molt Contagious?
French molt is highly contagious and not just among budgies. Other members of the Psittacidae family can also catch it, so be mindful of homing budgies and parrotlets in the same cage. While adults won’t suffer from the virus, other young birds most assuredly will.
If you suspect your budgie has French molt, it should be quarantined. Work to keep the budgie warm, comfortable, and entertained in a new cage. The budgie will live alone for the rest of its life and can’t fly for exercise, so the cage must meet all its needs.
Once the infected budgie has been removed from the shared enclosure, sanitize the cage. Temporarily rehome any other birds and clean every habitat surface, cleaning up any droppings.
French molt is not zoonotic. As the name suggests, avian polyomavirus won’t impact mammals or humans. All the same, wear gloves and protective clothing during cleaning.
Can Budgies Recover from French Molt?
Budgies can survive French molt if the condition is caught early enough. Some budgies even regrow the feathers they lose, although avian polyomavirus renders a budgie incapable of flight for life. If French molt were particularly serious, the budgie would likely endure abnormal feather growth for life.
Overall, how long do French molt budgies live? Typically, if a budgie survives for 12 weeks or later, the risk to its life is significantly reduced. As per the Journal of Virology, avian polyomavirus rarely results in a cancerous tumor despite its status as a papovavirus.
This doesn’t mean the budgie has cast off French molt, but the symptoms are no longer an immediate danger to its life. Focus your attention on hatchlings at risk of the virus. A budgie that develops French molt in its first 2 weeks of life is almost certain not to survive.
Treatment for French Molt in Budgies
French molt has no cure, so an avian vet won’t prescribe antibiotics or other medication to reverse the condition. You’ll need to isolate and separate the infected bird and provide the care it needs to enjoy a full life, despite its inability to fly.
A vet may offer an antiviral medication designed to combat a different ailment. While there’s no remedy for French molt, drugs exist that could ease some side effects and consequences.
Preventing French Molt in Budgies
Prevention and protection are vital as it’s impossible to cure French molt. Following these lifestyle guidelines will reduce the risk of your budgie developing French molt:
- Avoid subjecting young budgies to stress, such as loud noises and artificial light.
- Don’t house very young budgies with adults (other than parents) to reduce the risk of exposure to asymptomatic carriers of avian polyomavirus.
- Keep budgies in large enclosures, sharing space with the right number of conspecifics.
- Clean a budgie’s cage regularly – spot cleaning to remove droppings and feces should occur daily.
- Feed a balanced diet rich in protein and methionine. This is especially important if the young budgie wasn’t fed crop milk by its mother.
- Isolate and treat any budgie that shows signs of French molt.
A vaccine is available to protect birds, including budgies, from polyomavirus. The American Journal of Veterinary Research confirms that vaccination is safe and effective.
Sometimes, you may be unlucky after taking precautions. As discussed, some budgies are born with French molt, and the infection can’t be prevented.
Be vigilant about protecting young budgies from polyomavirus, as this condition is life-threatening. If a young budgie is molting before it has left the nest, there’s every chance it has French molt.