Hygiene Protocols for the Prevention and Control of Diseases (Particularly Beak and Feather Disease) in Australian Birds
Department of the Environment and Heritage, 2006
As for Section 5, Actions 5.1 and 5.2 of the TAP stated that effective education and extension material for post-mortem protocols are needed by field workers and wildlife managers, to promote detection of the disease in priority species of psittacine birds and an assessment made of the true impact of PBFD. Once again, the materials is to be distributed to wildlife managers, veterinarians, wildlife carers and aviculturists to assist in the detection of disease in priority species.
A necropsy (post mortem examination, autopsy) is the examination and dissection of a body after death to determine the cause of death, to investigate disease states present and identify changes produced by disease prior to death. The word “autopsy” is reserved for a post mortem examination of humans, “necropsy” for animals.
In the field, a necropsy will provide information on the general health of a species in an area, and is an important facet of studying a particular disease of one or more species of birds in an area, or a country.
A necropsy requires a systematic examination of the entire carcase and the collection of samples for aids to diagnosis. Fresh carcases (not frozen) are preferred to those that are decomposed or thawed. When frozen carcases are thawed, ice crystals penetrate the cell membranes which allows cytoplasmic fluids to escape, resulting in a carcase “swimming” in red-tinged fluid. The slower the thawing process, the less fluid escapes.
Any person performing, or assisting with, a necropsy should be aware of:
- All methods of pathogen transmission (PDF - 22 KB).
- Any zoonotic diseases (PDF - 15 KB) associated with birds.
- Aseptic technique for specimen collection.
- How to protect themselves (PDF - 24 KB) from contamination.
- How to dispose of contaminated equipment.
- How to dispose of carcases.
- How to forward specimens (PDF - 51 KB) to a laboratory.
Persons conducting an avian necropsy must know how to conduct one, and know the “normal.” A field necropsy should be carried out by a person who has been trained in the technique. This includes veterinarians who may have conducted necropsies only on mammals. Smokers and persons with known immunosuppression should not perform necropsies.
Protective equipment should be worn during a necropsy. In a laboratory situation, and if chlamydophilosis or avian influenza is suspected, this consists of disposable hair cover (to prevent aerosols from entering the hair), disposable nitrile gloves, disposable P2 particulate filter face mask (PDF - 24 KB), safety glasses (that can be disinfected), disposable solid front gowns with cuffed sleeves that are either impermeable or covered with a PVC apron, and rubber boots. Personnel who cannot wear a P2 mask because of facial hair or other fit-limitations should wear loose fitting hooded or helmeted powered air purifying respirator (PAPR).
Gowns, gloves and masks should be discarded after the specimens have been processed. Remove the mask after the gown and gloves. Do not touch the mask front when removing the mask from the face - the mask tabs only should be touched.
Careful attention should be given to hand hygiene after removal of protective clothing and especially before touching the face, eyes or mucosal surfaces.
It is obvious that such precautions cannot be easily undertaken in the field, and operators should wear disposable nitrile gloves, safety glasses (that can be disinfected), overalls, a PVC apron (if the bird is greater than 4 kg), and rubber boots. Depending on ambient air flows, a disposable P2 particulate filter face mask may be worn.
For checklists of the post-mortem examination of captive and wild birds, see the following documents:
- A Full Necropsy Protocol (PDF - 39 KB) - post-mortem procedure for both captive and wild birds.
- Necropsy protocol for a bird with suspected PBFD (PDF - 83 KB)
- Avian Post Mortem Checklist 1 (PDF - 212 KB)
- Avian Post Mortem Checklist 2 (PDF - 321 KB)
- Equipment Lists (PDF - 37 KB)