Autopsy and Laboratory Diagnosis Flashcards
Personal protective equipment to ensure biosafety when doing a necropsy
- Gloves
- Coveralls
- Boots
Why do a postmortem?
- Confirm/reject clinical diagnosis
- Dealing with unknown disease = identify what disease processes are occuring to explain cause of death or clinical findings, collect tisues to conduct tests which will establish a cause (information may be needed to prevent or treat disease in other animals)
- Testing for agents without documenting pathological process is of limited use
When are you going to do a postmortem?
-As soon as possible
When are you going to examine other animals?
-Before doing a necropsy on the dead animals
Which animals will you do a postmortem on?
Dead ones
Where will you do the postmortem?
- Concrete
- Dirt area in sun
- Straw bed
What will you do with the carcasses?
- Burial
- Renderer
- Transport to a disposal site
- Incineration
- Composting
Areas to AVOID while doing a postmortem
- Areas accessible to animals
- Areas which may contain food
- High traffic areas
- Areas difficult to disinfect
GREAT postmortem sites
- Concrete
- Dirt area in sun
- Straw bed
Disposal options
- Burial
- Renderer
- Transport to a disposal site
- Incineration
- Composting
Biosecurity and biosafety
-All specimens should be handled and treated as though they are a potential zoonosis threat
Routes of exposure to pathogens during a postmortem
- Oral
- Splash
- Aerosolization
- Percutaneous (sharps injury)
What is the #1 route of exposure of pathogens during a postmortem?
Oral
BSL for routine necropsy of a domestic animal
2
BSL for animal suspected to have rabies
3
BSL for a person with immunosuppression/pregnancy
3
Equipment needed
- PPE
- Sharp knife
- Rib cutters
- Saw or axe for brain removal
- Forceps, scissors
- Jars, bags
- Swabs, tubes
Why is it important to inspect the premise and examine other animals?
- Toxic plants
- Good to check animals for clinical signs
Postmortem steps for ANY species
- External examination
- Open body cavities
- Collect microbiologic samples
- Remove and dissect organs
- Collect histologic samples
Foramlin will not penetrate more than ____ cm tissue.
1/2
Organs with a capsule need to be ______ in a histologic sample.
Incised - cut open!!
Formalin:Tissue ration
10:1
Don’t try to fix tissue that is more than _____ cm in diameter.
1
After the postmortem
- Clean and disinfect work surfaces
- Decontaminate self by removing gloves and coveralls, washing boots/vehicle tires/wheel bases
- Record necropsy findings
What body cavity do you open first?
Abdominal
Once the body cavities are open, which test do you sample for first?
Microbiology
Collecting Microbiologic samples
- Collected first
- Collected aseptically
- Sample intestine last due to fluid
- Keep samples cold with ice/gel packs
- Direct sample towards most likely cause
- Place fresh tissues in separate containers
- Collect generous tissue samples = swabs
Red top/plain sterile tube
Culture
EDTA/purple top
- Fluid analysis
- Cytology
Removing and dissecting organs
- Open ALL lumens
- Examine ingesta = foregin material, toxic plants, feed quality, etc.
- Evaulate mucosal surfaces
Collecting Histologic samples
- All organs of the body especially those with lesions
- Better for lab to discard unneeded samples than for the organ that is needed not be sampled
- Label tissues if needed
- Toxins = urine, stomach contents, fat
