Also known as Parrot fever, Psittacosis
Ornithosis occurs worldwide in all poultry species of all ages. It is a reportable disease and has a public health significance. It can also affect pet birds. Ornithosis is caused by an obligate intracellular bacterium- Chlamydia psittcai. Spread by faeces and airborne route.
- Causes of Ornithosis >
- Effects of Ornithosis >
- Diagnosis of Ornithosis >
- Treatment & Control of Ornithosis >
Causes of Ornithosis
It causes fever in man and Pscittacine birds.
The causative agent, Chlamydia psittaci, is an obligate intracellular bacterium. The organism has a complex development cycle, which result in a change from the elementary body to the Reticulate body in the host.
Mode of transmission
It is spread by faeces and airborne. Processing plant exposure may occur for humans.
Special note
Primarily turkeys on range and aviary birds are affected.
It has public health (can cause disease in humans) importance and is a notifiable disease. It can produce high fever, flu-like illness and mortality in humans; causes abortion in cattle. Cats and pigeons spread organisms. Veterinarians, pet bird owners and processing plant employees are a high-risk population.
Effects of Ornithosis
Signs include fever and sleepiness depending on the strain. Toxigenic strain causes high morbidity and mortality, whereas the non-toxic produces a mild respiratory or gastrointestinal disease.
There may be a drop in egg production and green droppings.
Postmortem lesions
There can be a fibrinous pericarditis, air sacculitis and hepatitis. Large congested spleen, pneumonia, congested kidneys, liver, swollen necrotic vent and brain haemorrhage (parrots) can be seen.
Diagnosis of Ornithosis
Eliminate CRD due to mycoplasma, ND or infectious bronchitis (IB) and E. coli. Laboratory isolation of organism in chicken embryos or mice. Serology (complement fixation) test, or latex agglutination test can be done. Recovered birds shed organism up to 42 days.
Giemsa stain from tissue impression smears reveal red EB’s or bluish-green RBs. Antigen capture ELISA will stain Chlamydia smear from swabs or vent or cleft (Abbot or Kodak, Labs.).
It simulates CRD, colibaccillosis, influenza and cholera. Fibrinous pericarditis, air sacculitis and congested spleen in turkeys is diagnostic.
Treatment & Control of Ornithosis
Prevention
Destroy dead birds, prevent wild and free-flying bird exposure and quarantine infected flocks.
Treatment
CTC 400 g/ton (3 weeks) and Doxycyline* are effective drugs.
*Not approved in the United States for use in commercial poultry
