7. Companion Bird Viral Diseases

Avian bornavirus and PDD

Proventricular dilation disease “PDD”: fatal disease of psittacines

Avian bornavirus and PDD caused by

Avian Bornavirus (RNA virus)

Avian Bornavirus and PDD Transmission

 fecal-oral (?) Vertical?

Avian Bornavirus and PDD Special characteristic

Lymphoplasmacytic ganglioneuritis: progressive destruction of brain, spinal cord, and peripheral nerves

Nerves of GI affected 

Food accumulation

PDD Clinical Signs

GI signs-weight loss, undigested seeds in feces, vomit and regurgitation

CNS Signs- Tremor, incoordination, blindness, seizures

Lethargy and Ruffled Feathers

Is PDD Clinical course unpredictable?

yes

ABV-positive birds can remain clinically healthy for years.

Periods of stress may induce clinical signs.

Poor prognosis once disease develops

PDD Diagnosis

Radiography (+/- contrast): enlarged proventriculus

Combination of RT-PCR + serology recommended for screening (repeated testing).

PDD Management

Test all birds of the household

Nutritional support

NSAID-celecoxib PO every day long term

PBFD Psittacine Beak and Feather Disease is caused by

Hemagglutinating Circovirus DNA

PBFD: Psittacine Beak and Feather Disease affects birds differently

Budgies

Lorikeets

Cockatoos and African Greys

Budgies-asymptomatic

Lorikeets may recover and become carriers and Spreaders

Cockatoos and African Greys++ susceptible

PBFD: Psittacine Beak and Feather Disease transmission

Horizontal transmission via feces, feather dander, regurgitation. Massive viral excretion!

PBFD what age is most susceptible

young birds

PBFD Acute Form effects?

Clinical signs?

Nestling or fledging birds-African grey parrot, black cockatoos

Fractures of developing feathers, intrapulp hemorrhage

edema of wing tips (vasculitis)

Leukopenia , anemia, green diarrhea, regurgitation, rapid death due to hepatic necrosis

PBFD Chronic Form Clinical Signs

Dystrophic feathers short

Cockatoos: loss of powder down (bare skin patches, glossy beak), abnormal beak and nails (overgrown, fractures etc)

Secondary infections from chronic immunosuppression

Difficulties in eating-hypoproteinemia, weight loss, death

PBFD diagnostics

Serology

PCR on blood and feathers (avoid cross contamination)

Skin and feather biopsy and postmortem histo findings 

PBFD Treatment and Prevention

Usually Terminal-euthanasia 

Supportive treatment-nutritional support

Test new birds, quarantine 

Avian Polyomavirus APV is what type of virus affecting who

DNA Virus-young psittacines

Avian Polyomavirus APV is also known as

Budgerigar Fledgling Disease

Affects 1-3 week olds

Clinical Signs for Budgies with APV

Acute lethargy, crop stasis, death

Cutaneous hemorrhage, ascites and head tremors may be seen Surviving budgerigars often show feather dystrophy (“runners”)

In other psittacines-nestlings/ juveniles (macaws, conures) what are the clinical signs

Depression, ascites, GI symptoms, bleeding, death

How is APV shed

For how long can it be shed

feces, crop secretions, skin, and feather dander. Ingestion +/- inhalation

shed for months 

Diagnosis of Avian Polyomavirus(APV)

PCR on blood to detect viremia + PCR on oral/cloacal swab to detect shedding

Serology and histopath

Treatment of Avian Polyomavirus (APV)

Supportive treatment

Prevention of Avian Polyomavirus

Test new birds, keep budgies separate from other breeding parrots

Psittacid Herpesvirus 1 is what type of virus

DNA virus

What 2 types of disease does Psittacid herpesvirus 1 cause in parrots of all ages

Pacheco disease (peracute fatal disease)

Mucosal papillomatosis

Pacheco disease characteristics

Highly contagious

Sudden death most common (multiple birds)

Sometimes preceded by depression, biliverdin-stained urates

PM: hepatic and splenic necrosis

Treatment: acyclovir PO (before bird dies…) Efficient to reduce mortality

Birds will remain carriers after treatment 

Macaws, Amazon parrots, Patagonian and sun conures are frequent subclinical carriers.

Mucosal papillomatosis Affects which birds

macaw and amazon parrots

Mucosal papillomatosis clinical signs

 Papillomas in oral cavity and cloaca-May wax and wane, disappear, or disseminate to GI tract

Blood in droppings, papilloma prolapses through cloaca

Upper GI signs (regurgitation, wasting disease) if dissemination

bile duct and pancreatic duct carcinomas → signs of chronic liver disease

Diagnosis of Mucosal Papillomatosis

Physical exam (oral cavity, eversion of cloacal mucosa)

PCR of cloacal/choanal swab

Mucosal papillomatosis Treatment

Surgical removal

Acyclovir unsuccessful 

Psittacid herpesvirus 1 Prevention

avoid introducing Sun/Patagonian conures into mixed aviaries

Repeat PCR testing 

biosecurity

Poxvirus infects which species of birds

Chicken, canaries, domestic pigeon, free range birds

Transmission of Poxvirus

Mosquito bites. fomites-penetrate via skin injury

Dry Pox

raised lesions on face (eyelids, mouth commissure), feet, under wings. Normally self-limiting (lesions regress in a few weeks). Low mortality.

Wet/Mucosal Pox

blepharitis, conjunctivitis, diphtheritic lesions of the oral cavity and trachea. High mortality in canary aviaries

Systemic Pox

acute onset of depression, anorexia, dyspnea, peracute death. Air sacculitis and pneumonia

Diagnosis of Poxvirus

clinical signs +/- histopathology

Treatment of Poxvirus

Supportive

Prevention of Poxvirus

modified live vaccine available for canaries and pigeons. Hygiene and biosecurity, vector control

Paramyxovirus type 1 Exotic Newcastle Disease clinical signs

Depression, anorexia, respiratory symptoms, diarrhea, ataxia, torticollis (CNS signs)

Pigeon paramyxovirus-1 clinical signs

CNS signs (trembling, ataxia, paralysis..), diarrhea, polyuria

Several birds affected

When should you vaccinate pigeons to prevent Paramyxovirus type 1

>6 weeks prior to racing season

Avian influenza (AI) affects which species

birds housed outdoors: backyard chickens, zoo birds…

West Nile Virus and Eastern Equine encephalitis is caused by which virus

Mosquito-born Flavivirus

Are birds reservoirs for West nile virus and eastern equine encephalitis

Yes

Which birds and susceptible to West Nile Virus

Birds of Prey, crows, jay

Which birds are susceptible to EEE

pheasants, partridges, cranes, ratites

How do you diagnose West Nile Virus and Eastern Equine Encephalitis

PCR on tissues/oral swabs, virus isolation, serology