Psittacine Beak & Feather Disease (PBFD)
Would you know if your new budgie, cockatiel, lovebird, parrot, cockatoo or macaw had early signs of PBFD infection?
... and would you know what your options for helping your bird are?
Would you know if one or more of your birds is a carrier of PBFD Circovirus?
Your Gold Coast Bird Specialist Dr Ross Perry can help you!

"Matilda", a delightful mischievous sulphur crested cockatoo with chronic PBFD who loved me and was jealous of my computer and destroyed my keyboard twice on one day
Your Gold Coast Bird Vet Specialist Dr Ross Perry is a world leader on this disease PBFD. Dr Ross Perry was the first vet to describe the disease, name it and prove that is is associated with a psittacine circovirus infection. And that was only the beginning...
The following notes are a small section of the chapter on PBFD from the book by Dr Ross Perry called "Caring for Birds with Love and Gratitude". I suggest that you click the underlined title to order your copy of "Caring for Birds with Love and Gratitude" now.
There is evidence that PBFD has affected Australian cockatoos and parrots for many years; perhaps it has been here for eons, but it was back in 1971-72 that as a new graduate I studied my first case in a sulphur crested cockatoo and became interested in this disease which I originally described as beak rot and then subsequently gave the name by which it is now known. PBFD is sometimes also known as Psittacine Circovirus Disease (PCD). PBFD is currently considered around the world to be one of the most important viral diseases of budgies and other parrots, lories, lorikeets, cockatoos and macaws.
Why is PBFD such an important disease?
PBFD is a very common widely spread disease that is not curable with conventional allopathic treatments that is associated with spread of circoviruses and their components through most parts of the body. PBFD can be associated with progressive replacement of normal feathers by deformed quills, beak deformity, disease of many internal organs (including thymus, bursa of Fabricius, liver, spleen, intestines, lungs, nervous system), green bubbly diarrhoea, a reversal to more juvenile behaviour and an acquired immuno-dysfunction predisposing other diseases. It can be associated with acute disease and “sudden death” in young birds, especially nestlings, to a very chronic disease and “slow death” in mature cockatoos. The appearance of the disease in one species of parrot is often very different from its appearance in another.
How does PBFD affect budgies?
PBFD usually clinically affects budgies initially when they are nestlings and fledglings. The younger nestlings usually die. Older nestlings and fledglings develop acute disease that affects and often halts the growth of blood quill feathers such that they die and fall out or grow with malformations. Many affected budgies lose the ability to fly and are called runners because they run along the ground. About 40-60% of these budgies recover normal plumage over 1-2 moults but some are likely to remain carriers of the circoviruses and some can develop beak and nail deformities and other forms of chronic disease. Beak deformities associated with PBFD in young budgies occur uncommonly whereas they are very common in cockatoos.
Why do you say PBFD is associated with Circoviruses rather than caused by Circoviruses?
We usually think in terms of the common cold being caused by a common cold virus, chicken pox being caused by "chicken pox virus" and pregnancy by "sex" and yet if we take time to think about it we can be exposed to the common cold virus in massive doses without becoming sick with a cold, we can be exposed to "chicken pox virus" without getting chicken pox and we may experience "sex" without getting pregnant. So the term and the thinking associated with "caused by" is not strictly accurate and to my way of thinking represents a distortion, another “dumbing down of the masses” and gross oversimplification of the "truth" (using the scientific framework of beliefs). However, if we replace "caused by" with "associated with and a feature of" the thinking becomes much more accurate and allows recognition of a whole host of possible determinants which may influence whether or not a particular individual, group or species succumbs to disease and/or recovers from it. This is highly relevant to PBFD (I am sorry that when I first described this disease and gave it this name "Psittacine Beak and Feather Disease" I couldn't find a simpler name for it!).
Tell us more about the circoviruses!
After many years of research PBFD as we know it has been shown to be clearly associated with the birds' cellular responses to multiplication of perhaps the tiniest virus known to mankind (now called Psittacine Circovirus) containing a single strand of DNA in the form of a convoluted loop within certain actively growing cells of psittacine birds and the disease can readily be "transmitted" by inoculation of nestlings less than 10 days of age with the virus particles. As nestlings get older they appear to become increasingly resistant to succumbing to the infection, other factors being equal, but of course, they rarely if ever are equal, and hence we see a very wide range of "symptoms" and patterns of disease, depending on species, immune interaction, age and whether or not the disease is peracute, acute, sub-acute or chronic. The virus particles often also infect cells of the bird's immune system and this can progress to an AIDS-like syndrome further complicating the picture. It appears that some species of psittacines such as cockatoos (Cacatua spp.) are far more susceptible to the chronic form of the disease genetically than others such as budgerigars .
"You presume you are a small entity,
But within you is enfolded the entire universe.
You are indeed the evident book,
By whose alphabet the hidden becomes manifest.
Therefore, you have no need to look beyond yourself,
What you seek is within you, if only you reflect."
- Iman Ali Ibn Abi Taleb
Can budgies and other PBFD-susceptible birds being infected with other viruses and organisms at the same time as “having” PBFD?
In Australia some birds infected with psittacine circoviruses are concurrently infected with polyomaviruses which can induce similar disease to PBFD. Concurrent infection with other viruses , Chlamydophila, other bacteria and fungi is also likely. Our understanding of the interactions of these various viral infections with the immune systems of birds is still in its infancy.
Has French Moult got anything to do with PBFD?
“French or English or German or Australian Moult” are historical lay terms referring to acute infection with either psittacine circoviruses and/or polyomaviruses in which we choose to blame another country.
Are the circoviruses that infect budgies the same as those that infect cockatoos?
They are similar yet significantly different with respect to their dna sequences and their quantum mechanics vibrational frequencies. The quantum frequencies of budgie circoviruses are much closer to the circoviruses of cockatiels than those of lovebirds, cockatoos, corellas, orange-bellied parrots and other species evaluated by me and my associates. When Dr David Pass and I first described PBFD circovirus we thought the same virus infected many species of psittacine birds. Dr Mohammad Bassami completed a PhD at Murdoch Uni and showed there are significant differences in the genetic structure of PBFD Viruses from around Australia. This may or may not relate to antigenic or pathotype variation but it does have significant relevance to anyone doing DNA testing by PCR etc. Overall nucleotide identity rangedfrom 84% to 97% which could mean false negative results on some PCRs. Most of the genetic variation was due to a combination of point mutations and a number of deletions and insertions ranging from 1 to 17 nt in size.
Can the circoviruses of budgies infect the other species of birds?
At this point in time I am not sure. I suspect they can, however I suspect they would need to mutate to establish an infection with clinical disease.
How is PBFD spread from bird to bird?
The clinical disease is not spread as such. Instead, the circoviruses or their energy frequencies can pass from bird to bird and it depends on a complex array of factors as to whether or not the “receiving” bird is or will become susceptible to developing PBFD. Live PBFD viruses are passed from infected birds in saliva, faeces, skin and feather dander, feathers and other items such as clothing, hands, soil that have been in contact with them.
How long can circoviruses live and remain infectious in the environment in moulted feathers , faeces etc.?
Depending on factors such as exposure or otherwise to direct sunlight the PBFD circoviruses can remain potentially infectious for at least a year. Infected nesting logs and boxes are likely to be a source of infection from one breeding season to the next.
Obviously there is much more to know about PBFD. You can buy "Caring for Birds with Love and Gratitude" and explore what else Dr Ross Perry has written there. You can consult Dr Ross Perry personally. You can also explore one of his other websites under construction such as www.PsittacineBeakFeatherDisease.com or www.pbfdcircovirus.com.
Circoviruses are also associated with disease in other species of birds, such as ravens. Here is an abstract of a published paper on Circovirus Infection in Australian Ravens.
Identification of a novel circovirus in Australian ravens (Corvus coronoides) with feather disease.Meredith E Stewart, Ross Perry, Shane R Raidal
School of Veterinary and Biomedical Science, South St, Murdoch, Western Australia, 6150, Australia.
Avian Pathology (impact factor: 1.71). 05/2006; 35(2):86-92. DOI:10.1080/03079450600597345Source: PubMed
EditABSTRACT The complete genome of a novel Circovirus isolated from an Australian raven (Corvus coronoides) with feather lesions similar to those that occur in psittacine beak and feather disease is reported. Degenerate polymerase chain reaction primers were designed to amplify and sequence novel Circovirus DNA from affected feathers. Sequence analysis indicated that the tentatively named raven circovirus (RaCV) was 1898 nucleotides in size with two major open reading frames synonymous with other avian circoviruses, ORF C1 and ORF V1, likely to encode a putative capsid protein (Cap) and replicase-associated protein (Rep), respectively. In common with other circoviruses was the conservation of several nucleotide structures and amino acid motifs implicated in virus replication. Comparison with other members of the Circoviridae demonstrated that RaCV shares the greatest sequence homology with canary circovirus (CaCV) and pigeon circovirus (PiCV) and was more distantly related to the beak and feather disease virus, goose circovirus, duck circovirus and the two porcine circoviruses, PCV1 and PCV2. Phylogenetic analysis of the genome and the putative Cap and Rep proteins provided further evidence of the close relationship of RaCV with CaCV and PiCV.
The following notes are a small section of the chapter on PBFD from the book by Dr Ross Perry called "Caring for Birds with Love and Gratitude". I suggest that you click the underlined title to order your copy of "Caring for Birds with Love and Gratitude" now.
There is evidence that PBFD has affected Australian cockatoos and parrots for many years; perhaps it has been here for eons, but it was back in 1971-72 that as a new graduate I studied my first case in a sulphur crested cockatoo and became interested in this disease which I originally described as beak rot and then subsequently gave the name by which it is now known. PBFD is sometimes also known as Psittacine Circovirus Disease (PCD). PBFD is currently considered around the world to be one of the most important viral diseases of budgies and other parrots, lories, lorikeets, cockatoos and macaws.
Why is PBFD such an important disease?
PBFD is a very common widely spread disease that is not curable with conventional allopathic treatments that is associated with spread of circoviruses and their components through most parts of the body. PBFD can be associated with progressive replacement of normal feathers by deformed quills, beak deformity, disease of many internal organs (including thymus, bursa of Fabricius, liver, spleen, intestines, lungs, nervous system), green bubbly diarrhoea, a reversal to more juvenile behaviour and an acquired immuno-dysfunction predisposing other diseases. It can be associated with acute disease and “sudden death” in young birds, especially nestlings, to a very chronic disease and “slow death” in mature cockatoos. The appearance of the disease in one species of parrot is often very different from its appearance in another.
How does PBFD affect budgies?
PBFD usually clinically affects budgies initially when they are nestlings and fledglings. The younger nestlings usually die. Older nestlings and fledglings develop acute disease that affects and often halts the growth of blood quill feathers such that they die and fall out or grow with malformations. Many affected budgies lose the ability to fly and are called runners because they run along the ground. About 40-60% of these budgies recover normal plumage over 1-2 moults but some are likely to remain carriers of the circoviruses and some can develop beak and nail deformities and other forms of chronic disease. Beak deformities associated with PBFD in young budgies occur uncommonly whereas they are very common in cockatoos.
Why do you say PBFD is associated with Circoviruses rather than caused by Circoviruses?
We usually think in terms of the common cold being caused by a common cold virus, chicken pox being caused by "chicken pox virus" and pregnancy by "sex" and yet if we take time to think about it we can be exposed to the common cold virus in massive doses without becoming sick with a cold, we can be exposed to "chicken pox virus" without getting chicken pox and we may experience "sex" without getting pregnant. So the term and the thinking associated with "caused by" is not strictly accurate and to my way of thinking represents a distortion, another “dumbing down of the masses” and gross oversimplification of the "truth" (using the scientific framework of beliefs). However, if we replace "caused by" with "associated with and a feature of" the thinking becomes much more accurate and allows recognition of a whole host of possible determinants which may influence whether or not a particular individual, group or species succumbs to disease and/or recovers from it. This is highly relevant to PBFD (I am sorry that when I first described this disease and gave it this name "Psittacine Beak and Feather Disease" I couldn't find a simpler name for it!).
Tell us more about the circoviruses!
After many years of research PBFD as we know it has been shown to be clearly associated with the birds' cellular responses to multiplication of perhaps the tiniest virus known to mankind (now called Psittacine Circovirus) containing a single strand of DNA in the form of a convoluted loop within certain actively growing cells of psittacine birds and the disease can readily be "transmitted" by inoculation of nestlings less than 10 days of age with the virus particles. As nestlings get older they appear to become increasingly resistant to succumbing to the infection, other factors being equal, but of course, they rarely if ever are equal, and hence we see a very wide range of "symptoms" and patterns of disease, depending on species, immune interaction, age and whether or not the disease is peracute, acute, sub-acute or chronic. The virus particles often also infect cells of the bird's immune system and this can progress to an AIDS-like syndrome further complicating the picture. It appears that some species of psittacines such as cockatoos (Cacatua spp.) are far more susceptible to the chronic form of the disease genetically than others such as budgerigars .
"You presume you are a small entity,
But within you is enfolded the entire universe.
You are indeed the evident book,
By whose alphabet the hidden becomes manifest.
Therefore, you have no need to look beyond yourself,
What you seek is within you, if only you reflect."
- Iman Ali Ibn Abi Taleb
Can budgies and other PBFD-susceptible birds being infected with other viruses and organisms at the same time as “having” PBFD?
In Australia some birds infected with psittacine circoviruses are concurrently infected with polyomaviruses which can induce similar disease to PBFD. Concurrent infection with other viruses , Chlamydophila, other bacteria and fungi is also likely. Our understanding of the interactions of these various viral infections with the immune systems of birds is still in its infancy.
Has French Moult got anything to do with PBFD?
“French or English or German or Australian Moult” are historical lay terms referring to acute infection with either psittacine circoviruses and/or polyomaviruses in which we choose to blame another country.
Are the circoviruses that infect budgies the same as those that infect cockatoos?
They are similar yet significantly different with respect to their dna sequences and their quantum mechanics vibrational frequencies. The quantum frequencies of budgie circoviruses are much closer to the circoviruses of cockatiels than those of lovebirds, cockatoos, corellas, orange-bellied parrots and other species evaluated by me and my associates. When Dr David Pass and I first described PBFD circovirus we thought the same virus infected many species of psittacine birds. Dr Mohammad Bassami completed a PhD at Murdoch Uni and showed there are significant differences in the genetic structure of PBFD Viruses from around Australia. This may or may not relate to antigenic or pathotype variation but it does have significant relevance to anyone doing DNA testing by PCR etc. Overall nucleotide identity rangedfrom 84% to 97% which could mean false negative results on some PCRs. Most of the genetic variation was due to a combination of point mutations and a number of deletions and insertions ranging from 1 to 17 nt in size.
Can the circoviruses of budgies infect the other species of birds?
At this point in time I am not sure. I suspect they can, however I suspect they would need to mutate to establish an infection with clinical disease.
How is PBFD spread from bird to bird?
The clinical disease is not spread as such. Instead, the circoviruses or their energy frequencies can pass from bird to bird and it depends on a complex array of factors as to whether or not the “receiving” bird is or will become susceptible to developing PBFD. Live PBFD viruses are passed from infected birds in saliva, faeces, skin and feather dander, feathers and other items such as clothing, hands, soil that have been in contact with them.
How long can circoviruses live and remain infectious in the environment in moulted feathers , faeces etc.?
Depending on factors such as exposure or otherwise to direct sunlight the PBFD circoviruses can remain potentially infectious for at least a year. Infected nesting logs and boxes are likely to be a source of infection from one breeding season to the next.
Obviously there is much more to know about PBFD. You can buy "Caring for Birds with Love and Gratitude" and explore what else Dr Ross Perry has written there. You can consult Dr Ross Perry personally. You can also explore one of his other websites under construction such as www.PsittacineBeakFeatherDisease.com or www.pbfdcircovirus.com.
Circoviruses are also associated with disease in other species of birds, such as ravens. Here is an abstract of a published paper on Circovirus Infection in Australian Ravens.
Identification of a novel circovirus in Australian ravens (Corvus coronoides) with feather disease.Meredith E Stewart, Ross Perry, Shane R Raidal
School of Veterinary and Biomedical Science, South St, Murdoch, Western Australia, 6150, Australia.
Avian Pathology (impact factor: 1.71). 05/2006; 35(2):86-92. DOI:10.1080/03079450600597345Source: PubMed
EditABSTRACT The complete genome of a novel Circovirus isolated from an Australian raven (Corvus coronoides) with feather lesions similar to those that occur in psittacine beak and feather disease is reported. Degenerate polymerase chain reaction primers were designed to amplify and sequence novel Circovirus DNA from affected feathers. Sequence analysis indicated that the tentatively named raven circovirus (RaCV) was 1898 nucleotides in size with two major open reading frames synonymous with other avian circoviruses, ORF C1 and ORF V1, likely to encode a putative capsid protein (Cap) and replicase-associated protein (Rep), respectively. In common with other circoviruses was the conservation of several nucleotide structures and amino acid motifs implicated in virus replication. Comparison with other members of the Circoviridae demonstrated that RaCV shares the greatest sequence homology with canary circovirus (CaCV) and pigeon circovirus (PiCV) and was more distantly related to the beak and feather disease virus, goose circovirus, duck circovirus and the two porcine circoviruses, PCV1 and PCV2. Phylogenetic analysis of the genome and the putative Cap and Rep proteins provided further evidence of the close relationship of RaCV with CaCV and PiCV.
|
Gold Coast Bird Vet Specialist Dr Ross Perry, 23 Cornwall Drive, Elanora 4221 consulting strictly by appointment. To make appointment please ring 07 55226124 or 0419693279 or 0435848778. Similarly long distance phone or Skype (DoctorRossPerry) or iChat (DoctorRossPerry) consultations.
|
|