Field necropsy techniques in mammal and poultryvphcap.vet.cmu.ac.th/GHI-Thailand2012/download... ·...
Transcript of Field necropsy techniques in mammal and poultryvphcap.vet.cmu.ac.th/GHI-Thailand2012/download... ·...
Field necropsy techniques in mammal and poultry
Kidsadagon Pringproa, DVM, MS, PhD
Department of Veterinary Biosciences and Veterinary Public HealthFaculty of Veterinary Medicine
Chiang Mai University2012
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What is a necropsy?
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• Systemic examination of animal carcass aimed to search for
lesions and study the processes involved in disease situation
• The important diagnostic tool to support other procedures in
the diagnosis of disease outbreak
• A good necropsy involves carefully observation of lesions,
labelling and storage
Objectives in necropsy
• To investigation the caused of ill or death animals by defining
possible etiology and pathogenesis
• To provide information and support other procedures of
disease diagnosis (collection of specific organs, etc....)
• To provide initial strategy in control and prevention of un-
infected herds
The better job you do with the field necropsy, the better the chance that wildlife disease specialist can
determine what killed animal.
Necropsy requirements
• at the discretion of attending veterinarian
• When a high death loss occuring
• When a significant unexplained death occuring
• When a strong chance of infectious disease in present
A necropsy must be performed;
The necropsy must be performed by or under the direct
supervision of a veterinarian experienced with species
being necropsied.
5http://vetmed.illinois.edu/envirovet/programdeveloped.html
Necropsy requirements
It is recommended but not required that all death elephants be necropsied.
Objectives for this session
• Get an idea how pathology involves in “one health” concept
• Use images to review step-by-step procedures for field
necropsy procedure
• Understand the collection of appropriate tissue specimens for
diagnostic investigation
Limitation of necropsy
• Time for necropsy
• Place for necropsy
• Animals died from suspected transmissible, zoonotic or
exotic diseases should be examined in a laboratory !!!
• Disposal of the carcass
• Basic equipments and protective clothing for necropsy
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Necropsy equipment
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Equipment for sample collection
10% formalin Microbiology collection tools
Carcass submission form
1. Signalment: species, breed, sex, age, weight, identify marks
2. History and clinical diagnoses
3. Clinical pathology
4. External appearances
State of nutrition
Mucous membrane, body orifices
General conformation, superficial lesions
Hair coat, parasite
History taking
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Very important in determining the potential zoonoticdiseases, organs should be collect and types of laboratory
test should be performed !!!
Necropsy techniques in large and small
animals
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Necropsy procedure
• Follow external examination (general appearance)
• Follow internal examination ( necropsy )
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General appearances
– Natural orifices
– Eyes
– Posture
– Limb and joint palpation
– Lymph nodes
– Skin surface
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External examination
Open the carcass
• dorsal recumbency• Reflect front and rear legs
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• Make a tab of skin beginning under
the mandibles
• Pull up on the tap and reflect skin
while cutting through the sternum
Open the carcass
Small animal
Dorsal recumbency and cut the sternum through the costochondral
junction
Large animal
Left lateral recumbency and cut the ribs by using a pincer
Open the thorax
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Examine the lesions and prepare for collecting samples
stomach
trachea
lung
liver
intestine
Open the carcass
Open the thorax
Remove the tongue, esophagus, trachea, lung and heart
heart
Examine the lung, check for pneumonia and collect samples
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In a large animal, intestinal and thoracic organs may have to be remove separately
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Remove the intestine by cutting of the large and small intestines
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Examination of the stomach
String out the small intestine by cutting the mesentery
Examination of the intestine
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• Randomly sectioning of the intestine
(5-10 cm.) to observe the intestinal
mucosa
• Jejunum, ileum, cecum and colon:
two 10 cm section fresh/chilled, four 1
cm section fixed
Sampling techniques of the intestines
Examine the liver
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Examine the pericardium Fibrinous pericarditis
Examine the myocardium and endocardium
Nasal swab and snout scoring
Open the joints to examine the synovial fluid
Necropsy technique in poultry
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http://partnersah.vet.cornell.edu/Avian-Necropsy-Examination-Introduction
Additional resources
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Before necropsy
Wet the feathers with soapy water to avoid masses of flying feathers
Be careful of nasal and mouth orifices
Physical and external examination
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Check for the mucus membrane, and nasal swab if desired
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Open the abdominal cavity
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Keel bone
Intestine
liver
Open the abdominal cavity
trachea
Open the thorax
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Open the trachea
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lung
Examination of the visceral organs
heart
Examination of the visceral organs
intestine Gizzard and proventriculus
proventriculus
gizzard
Examination of the bones and head
Bone and skull are opened
Necropsy report
Morphologic findings
Morphologic diagnoses
Tentative diagnoses
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Tissue preservation for histopathology
Fixative
1. Neutral buffered formalin 10% (1 liter)
• Formaldehyde (40%) 100 ml.
• Distilled water 900 ml.
• Sodium phosphate mono. 4 g.
• Sodium phosphate dibasic 6.5 g.
2. Bouins solution (for endocrine disease, eye)
3. Glutaraldehyde (for electron microscopy examination)
4. Alcohol (not a good fixative)
Fix 24-48 hrs. Room temp.
Tips for sample collection
Formalin fixation
Work TM. 2000. Avian necropsy ,manual for biologist in remote refuges.
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Summary
• Necropsy technique in small mammal
• Necropsy techniques in poultry
• Tip for sample collection from carcass
Acknowledgements
Faculty of Veterinary Medicine, Chiang Mai University
• Assist. Prof. Panuwat Yamsakul, DVM
• Kittikorn Boonsri, DVM, MS
• Jiraporn Sritan, DVM, MS
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