Necropsy Flashcards
Describe why you would do a necropsy.
-teaching, zoonosis, cause of death, cause of illness, monitor flock or herd health to develop T & P, determine effect of treatment, collect samples, legal or insurance purpose
Describe good & bad post Mortem sites.
- Good
-concrete, dirt area in sun, tarped area - Avoid
-areas accessible to animals/people
-areas that have food
-high traffic areas
-areas difficult to disinfect
Describe disposal options.
-burial, rendering, transport to disposal site, incineration/cremation, composting
>need to know local, state, federal regulations
>method of euth may impact disposal options
Describe biosecurity & biosafety.
-all specimens handled like they contain zoonotic pathogens
Describe routes of exposure to pathogens during a PM.
-oral/nasal/ocular mucous membranes
-aerosolization
-percutaneous
Describe PPE.
- Sharp knife/sharpener
- Rib cutters
- Saw or axe for brain removal
- Forceps,scissors
- Jars with screw-top lids
- Sample bags
- Swabs, tubes
- vaccinated for rabies
Describe sampling equipment.
-sterile containers (not overfill or narrow neck)
-seal plastic bags
-pipettes, needles, syringe
-blood tubes (purple & red)
-slides
-swab sticks
-fixative
-marker
Describe how you select the patient.
-singleton if a flock or herd problem of typical history & signs, recently developed
-freshly dead or avail for euth
-history & CS
-inspect environ
-examine other animals
Describe how you sample the live animal.
-clotted blood
-EDTA blood (blood films)
-urine
-discharge
Describe euth.
-restraint
-gunshot
-captive bolt (exsangination, pithing)
-cervical dislocation
-barbiturate overdose (tranquilizer)
Describe the standard operating procedure.
-ruminants = L side down bc rumen on L
-horses = R side down bc cecum on R
-pigs, poultry = dorsum down
-comprehensive (orderly from top to bottom)
-priorities systems indicated by CS
Describe the PM steps for any species.
- Ext exam
-surrounds, skin, hair, wool, feet, claws, orifices, mucous membranes, udder, genitalia - Open bod cavity
- Collect samples
- Remove & dissect organ
- Collect histology, toxicology, virology, parasitology samples
-int parasites preserved in ethanol
-live ticks in vials & refrigerated w moist cotton balls for 7-10d
Describe evaluating body condition.
-good, moderate, poor BCS
-eval muscle mass & fat stores
>SQ, visceral, bone marrow
*atrophy of fat = starvation
Describe subcutis, muscle, bones, joints.
Reflect forelimb
Reflect hindlimb
Skin limbs
Incise muscles
Open joints
Incise skin from forelimb to chin
Incise and reflect skin of neck and abdomen
Open abdomen from costal arch, to back, to pubis
Detach diaphragm
Remove or reflect ribs; ‘crack’ one.
Describe sample types.
- Bacteriology, virology
-aseptic collection
-tissue, exudate, feces (swab)
-impression smear of lesion - Toxicology
-liver, kidney, ingesta, fat, urine - Parasitology (ruminants)
-aliquots, abomasum, intestine wash, feces
Describe collecting microbiological samples.
-aseptic
-fresh tissue in sterile container
-samples cold w ice/gel pack (not wet)
-both normal & abnormal of all organs of the body!
-10:1 ratio of formalin to tissue
-sections 1cm thick MAX
-organs w capsule incised or capsule removed
-small animals (<100g) fixed whole
Describe cavitary effusions.
-red top or plain = sterile tube for culture
-EDTA (purple) = fluid analysis & cytology
Describe the abdominal cavity.
Inspect the abdominal cavity and organs.
Collect urine, and Multistix test if appropriate.
Remove the omentum.
Remove, inspect and incise the liver and gall bladder.
Tie off and transect the duodenum and rectum.
Remove, inspect and open the intestines.
Remove, open and inspect the omasum and abomasum.
Remove, open and inspect the rumen and reticulum.
Remove, inspect and incise the kidneys and adrenals. 1st bc small & can get messy
Remove and inspect the urinary bladder and genitalia.
*neg pressure in lungs bad = palpate
Describe the thoracic cavity & neck.
3:1 ratio between L ventricle & R ventricle wall thickness
Describe CNS.
-if necropsy is inconclusive or signs of CNS disorder = removed & inspect brain & place in fixative (take unfixed samples first)
1. Signs are ataxia or paralysis = sample spinal cord
2. Signs of blindness = place eye in fixative or collect eye fluid
Describe after the PM.
-clean & disinfect work surface
-decontaminate self
-record necropsy findings
-pack & ship samples according to Cat B biological substances (avoid glass)
*dont have to freeze formalin
Describe the triple pack system.
- Leak proof primary container
- Leak proof secondary container
- Absorbent material
Describe what your pathologist will tell you about a sample you sent.
- Confirm lesion or not
- Clinical sig
- Etiology & pathogenesis
- Differential diagnosis
- Confirmatory diagnostics
