Practical Necropsy Guide
Large Necropsy Binder for PDF 4/22/02 9:47 AM Page 2
Introduction
This guide is intended to aid beef cattle veterinarians as they discuss
the value of performing necropsies with their clients. Beef cattle
veterinarians can use this guide with clients to increase their
understanding of proper necropsy techniques and resulting methods
of diagnosis.
This guide has three parts:
• The first is a collection of images comparing normal organs with
common cattle health abnormalities.
• The second is a review of practical necropsy procedures.
• The third is a set of guidelines for proper tissue sampling techniques
and submission procedures.
This guide is not intended to be a fully comprehensive reference and should only be used in conjunction with veterinary consultation.
1
Elanco Animal Health Practical Necropsy Guide
Large Necropsy Binder for PDF 4/22/02 9:47 AM Page 3
2
Eyes
Conjun ctivitis — variety of causes, including:IBR, mycoplasma, foreign bodies and other irritants
Corneal lesion, diffuse corneal edema, starts atperiphery Malignant Catarrhal Fever (MCF)
Normal eye
Corneal lesion, central corneal ulcer with neovascularization — pinkeye
Large Necropsy Binder for PDF 4/22/02 9:48 AM Page 4
Oral cavity, ulcers — BVD ( )
Muzzle, shallow ulcers typical of viral diseases— BVD, MCF, blue tongue and rinderpest
Oral cavity, ulcers, hard and soft palate — BVD
Normal oral tissues
3
Oral Cavity
Large Necropsy Binder for PDF 4/22/02 9:49 AM Page 5
Oral Cavity
4
Tongue, extensive ulcers (ruptured vesicles) —vesicular disease
Oral cavity, raised proliferative lesions, oftenwith irregular edges, hard palate — papularstomatitis
Pharynx, retropharyngeal cellulitis (A )caused by a penetrating wound (B ) — ballinggun injury
Notes
A
B
Large Necropsy Binder for PDF 4/22/02 9:50 AM Page 6
5
Esophagus, trauma ( ) — penetrating wound,resulting purulent peri-esophageal abscess
Normal esophagus, normal postmortem changewith mild anterior congestion and posteriorpallor resulting from postmortem bloat
Esophagus, bloat line at thoracic inlet; othersupportive evidence includes: history, pallorand edema of hindlimb musculature
Esophagus
Large Necropsy Binder for PDF 4/22/02 9:50 AM Page 7
Esophagus
6
Esophagus, shallow erosions — BVD
Esophagus, extensive linear ulcers — BVD
Notes
Pharyngeal mucosa removed from underlyingstructures, ulcers — BVD
Large Necropsy Binder for PDF 4/22/02 9:51 AM Page 8
Upper Respiratory Tract
7
Larynx, necrotic laryngitis ( ) — calf diphthe-ria
Larynx, laryngeal edema — allergic reaction;look for pulmonary edema or congestion
Larynx, chronic laryngitis, small ulcer onepiglottis (circled)/laryngeal polyp ( )
Normal larynx
Large Necropsy Binder for PDF 4/22/02 9:52 AM Page 9
8
Upper Respiratory Tract
Normal trachea, congestion, with intactmucosal lining — can be normal postmortemchange
Trachea, tracheitis, adherent fibrinonecroticpseudomembrane — IBR
Normal trachea
Nasal cavity (nasal septum removed), fibrinopurulent rhinitis — IBR
Large Necropsy Binder for PDF 4/22/02 9:53 AM Page 10
Upper Respiratory Tract
9
Trachea, tracheitis, adherent fibrinonecroticpseudomembrane — IBR
Trachea (cross section), edema in dorsalmucosa ( ) — “honker” syndrome
Notes
Large Necropsy Binder for PDF 4/22/02 9:54 AM Page 11
10
Lungs
Sampling procedures for lungs• Include tissue as indicated by clinical signs or • gross lesions• Fresh sample size: 4 cm cubes of affected tissue• Fixed sample size: 1 cm thick or less of affected • tissue
Bronchopneumonia, acute (shipping fever, typicalof pneumonic pasteurellosis) ( )
Fibrinous pleuropneumonia; consolidated lung ( ) with pleural fluid (oval) and fibrinous pleuri-tis; solid line denotes sternum
Normal lungs
Large Necropsy Binder for PDF 4/22/02 9:55 AM Page 12
Lungs
11
Subacute shipping fever with fibrinous pleuritis( )
Fibrinous pleuropneumonia (cut section)
Bronchopneumonia, advanced, progressive,early abscesses in older part of lesion ( )
Bronchopneumonia, chronic with abscesses (1 ), emphysema (2) and atelectasis (3)
Large Necropsy Binder for PDF 4/22/02 9:56 AM Page 13
Lungs
12
Chronic pneumonia with atelectasis Acute interstitial pneumonia (AIP); entire lungoverinflated; individual lobules slightly firm
Acute interstitial pneumonia (AIP) (cut section);interlobular edema and emphysema commonlyseen with AIP
Acute interstitial pneumonia (AIP)
Large Necropsy Binder for PDF 4/22/02 9:57 AM Page 14
Lungs
13
Acute interstitial pneumonia (AIP); note emphysema ( )
Embolic pneumonia (multifocal lesions through-out lung) ( ) — hematogenous spread of bac-teria from lesions such as endocarditis and liverabscesses
Aspiration pneumonia (gangrenous), necroticlesion ( )
Parasitic pneumonia — note lung worms(Dictyocaulus viviparus) in opened bronchi ( )
Large Necropsy Binder for PDF 4/22/02 9:58 AM Page 15
Lungs
14
Pulmonary granuloma — tuberculosis ( ) Lymph node, granuloma — tuberculosis
Notes
Large Necropsy Binder for PDF 4/22/02 9:59 AM Page 16
15
Normal heart Normal heart
Heart, endocarditis ( ) — blackleg Heart, pericarditis — blackleg
Heart
Large Necropsy Binder for PDF 4/22/02 10:00 AM Page 17
16
Heart
Heart, fibrinous pericarditis (pericardial sacreflected) — Haemophilus somnus and otherbacteria
Heart, dilated right ventricle, rounded appearance — right heart failure
Heart, eosinophilic myositis (note pale areas inendocardium and myocardium)
Heart (cross section), beef measles, tapewormcysts of Taenia bovis ( )
Large Necropsy Binder for PDF 4/22/02 10:01 AM Page 18
Heart
Heart (cross section), myocarditis —Haemophilus somnus
17
Notes
Heart, myocarditis — Haemophilus somnus,lesions most frequently located in papillarymuscle ( )
Large Necropsy Binder for PDF 4/22/02 10:02 AM Page 19
18
Liver
Normal liver Normal liver, postmortem changes; superficialdiscoloration is common; incise lesion todetermine significance
Liver, abscesses Liver, nutmeg liver/accentuated lobular patterncommonly associated with chronic congestion,often due to heart failure
Large Necropsy Binder for PDF 4/22/02 10:03 AM Page 20
Liver
19
Liver (cross section), thrombophlebitis, sec-ondary to liver abscesses
Liver, focal hemorrhage or necrosis; bacillaryhemoglobinuria; necrotic lesion extends deepinto tissue
Liver, distended, thickened bile ducts — liverflukes ( )
Liver (dark pigmented tracts) — liver flukes
Large Necropsy Binder for PDF 4/22/02 10:04 AM Page 21
20
Urinary System
Kidney, acute pyelonephritis — ascending bac-terial infections
Kidney, renal infarcts ( )
Normal kidney
Large Necropsy Binder for PDF 4/22/02 10:05 AM Page 22
Urinary System
21
Kidney, pale moist cortex — tubular necrosis,usually due to toxins such as aminoglycosides
Kidney, hemoglobin stained due to hemolysis
Bladder, urethral calculus
Large Necropsy Binder for PDF 4/22/02 10:05 AM Page 23
22
Urinary System
Normal bladder
Bladder, urinary calculi and cystitis Penile urethra, calculusKidney, early hydronephrosis
Large Necropsy Binder for PDF 4/22/02 10:06 AM Page 24
Gastrointestinal
23
Normal rumen; postmortem changes, looseningof rumen lining
Rumen — chronic rumenitis; note shortenedpapilli and scarring ( )
Rumen, inflammation — rumenitis, mycotic;may be secondary to acidosis
Large Necropsy Binder for PDF 4/22/02 10:07 AM Page 25
24
Gastrointestinal
Rumen, ulcers on rumen pillar Rumen, erosions — BVD
Abomasum, chronic ulcer ( )Omasum, mycotic lesion may be secondary toacidosis
Large Necropsy Binder for PDF 4/22/02 10:08 AM Page 26
Gastrointestinal
25
Abomasum, small ulcers — (BVD) Abomasum, parasites — Ostertagia spp.
Notes
Large Necropsy Binder for PDF 4/22/02 10:16 AM Page 27
Gastrointestinal
26
Normal small intestine, typically thin-walledand pale
Small intestine, hemorrhagic enteritis —Salmonellosis; note thickened mucosa andbloody contents
Small intestine, inflammation — Salmonellosis;note enlarged lymph nodes ( )
Normal mesenteric lymph nodes
Large Necropsy Binder for PDF 4/22/02 10:17 AM Page 28
27
Gastrointestinal
Gall bladder and small intestine, fibrinous casts( ) — Salmonellosis
Small intestine, acute enteritis
Small intestine, Peyer’s patch necrosis — BVD Small intestine, Peyer’s patch necrosis — BVD
Large Necropsy Binder for PDF 4/22/02 10:18 AM Page 29
Gastrointestinal
28
Small intestine, parasites — nodular worm,Oesophagostomum ( )
Small intestine, proliferative enteritis (Johne’s),not seen in animals less than two years of age
Notes
Large Necropsy Binder for PDF 4/22/02 10:18 AM Page 30
29
Normal mesenteric lymph nodes
Gastrointestinal
Normal large intestines
Spiral colon, hemorrhagic mucosa — coccidiosis
Large intestine, inflammation — coccidiosis
Large Necropsy Binder for PDF 4/22/02 10:19 AM Page 31
30
Gastrointestinal
Large intestine, inflammation — coccidiosis
Notes
Large Necropsy Binder for PDF 4/22/02 10:19 AM Page 32
31
Musculoskeletal
Hindlimb — blackleg ( )
Normal hindlimb musculature
Hindlimb muscle — blackleg ( ); normal onright
Large Necropsy Binder for PDF 4/22/02 10:20 AM Page 33
32
Musculoskeletal
Hindlimb muscle, myodegeneration with cavitation — injection site
Hindlimb muscle, severe myodegeneration —injection site; walled off area can retain signifi-cant antimicrobial levels for prolonged periods ( )
Muscle, scar — injection site; muscle tissue isreplaced by scar tissue and fat
Notes
Large Necropsy Binder for PDF 4/22/02 10:21 AM Page 34
33
Musculoskeletal
Normal joint; note clear, tenacious joint fluid ( )
Hock joint, acute synovitis; note excess cloudyfluid with fibrin ( )
Stifle joint, synovitis with large fibrin clots
Large Necropsy Binder for PDF 4/22/02 10:22 AM Page 35
Brain
34
Normal brain
Brain, meningitis with congested vessels andcloudy meninges
Brain, polioencephalomalacia with flattenedcerebral gyri and cerebellar coning ( )
Large Necropsy Binder for PDF 4/22/02 10:22 AM Page 36
35
Brain
Brain, laminar cortical necrosis ( ) — polioencephalomalacia (formalin-fixed tissue)
Brain, brain stem hemorrhage ( ),Haemophilus somnus (fresh tissue)
Brain, laminar cortical necrosis ( ) — polioencephalomalacia (fresh tissue)
Brain, brain stem hemorrhage ( ),Haemophilus somnus (formalin-fixed tissue)
Large Necropsy Binder for PDF 4/22/02 10:23 AM Page 37
Brain
36
Brain, abscess ( )
Notes
Large Necropsy Binder for PDF 4/22/02 10:24 AM Page 38
37
Practical Necropsy Procedures
This section is intended to illustrate a set of practical procedures for
performing necropsies on feedlot cattle.
Understand and follow the requirements of your animal disposal
service, especially regarding the proper technique used in opening
the animal’s hide for thorough examination, as well as the specific
policy for picking up animals whose cranium has been opened.
Procedures
Large Necropsy Binder for PDF 4/22/02 10:24 AM Page 39
Procedures
38
Examine conjunctiva and cornea.Note inflammation, opacity and ulceration.
Examine oral cavity.Note lesions, such as ulceration.
Start with the calf’s left side down. Do an overall external examination.
Record animal I.D.
1
3
2
4
Large Necropsy Binder for PDF 4/22/02 10:24 AM Page 40
Reflect both right legs. Thoroughly exposepelvis to mandible. Make cut on ventral midlineto maximize hide value.Note hemorrhages, inflammation and injectionsites.
Reflect abdominal wall and omentum.Note fluid, fibrin, inflammation and location of viscera.
5 6
Cut near the sternum (A ) and several inchesbelow the spine (B ) with the cuts ending justdorsal and ventral to the trachea.
Alternative methods include the careful use of a sharp axe.
Knife method for rib reflection. Cut through costochondral junction and through intercostal muscles to reflect two ribs at a time by twisting and breaking (works best in younger animals).
7 8
Procedures
39
A
B
Large Necropsy Binder for PDF 4/22/02 10:24 AM Page 41
Procedures
40
Cut diaphragm and reflect rib cage. Examine pericardial sac in situ.Note presence of exudation, adhesions and extentof involvement.
9
Free tongue, esophagus, larynx and trachea.Examine pharyngeal area.
Cut ventral to the spine and dorsal to the sternum to free thoracic organs.
Open entire length of esophagus. Open larynx and trachea.Note mucosal integrity and differentiate inflamma-tory changes from agonal and postmortem changes(see page 8-9 for differential diagnosis photos).
10
11 12
Large Necropsy Binder for PDF 4/22/02 10:25 AM Page 42
Palpate and cut through lung tissue. See pages 10-14 for differential diagnosis.
Insert knife at the base of the heart, cutting tothe apex, exposing both ventricles.Note alteration in chamber size, discoloration, inflammation and hemorrhage.
Incise papillary muscles.Note myocardial and valvular changes.
13 14
15
Incise and palpate liver.Note evidence of discoloration, enlargement, changes to bile ducts and consistency (see pages 18-19).
16
Procedures
41
Large Necropsy Binder for PDF 4/22/02 10:25 AM Page 43
Procedures
42
Incise right kidney (caudal to liver).Locate and incise left kidney. Avoid cuttingintestines.Note areas of discoloration.
Examine mucosa of several segments of smallintestine.Note mucosal thickening, discoloration and exudation (see pages 26-28).
17 18
Incise mesenteric lymph nodes.Note enlargement.
Incise spiral colon and cecum.Note mucosal thickening, discoloration and exudation.
19 20
Large Necropsy Binder for PDF 4/22/02 10:26 AM Page 44
Incise reticulum (A), omasum (B) and abomasum (C).Note inflammation, ulceration and contents.
21
Determine rumen pH.Note inflammation and contents.
Examine rumen lining. Incise various muscles, depending on case history and other observations. Evaluate injection sites.
22
23 24
Procedures
43
Large Necropsy Binder for PDF 4/22/02 10:26 AM Page 45
Procedures
44
Expose stifle and other joints as deemed necessary.Note fluid amount and type.
Brain removal.*Make first cut A, 1/3 of the distance betweenthe eye and the poll. Cut B laterally from firstcut to the foramen magnum. Cut C immediatelyposterior to the foramen magnum.
Pry open cranium and cut through meninges.
25
26 27
* Understand and follow the requirements * of your animal disposal service regard-* ing the proper technique used in * opening the animal’s cranium for * thorough examination.
Remove and examine brain only when indications of Central Nervous System (CNS) disorders are indicated or there are no other significant necropsy findings.
*Use appropriate care in brain examination in areas where rabies is a possibility.
Large Necropsy Binder for PDF 4/22/02 10:26 AM Page 46
Cut spinal nerves and remove brain.
28
Cut brain into longitudinal halves and cross-section as appropriate.See pages 34-36 for differential diagnosis.
Replace organs into body cavity and close.
29
30
Procedures
45
Large Necropsy Binder for PDF 4/22/02 10:26 AM Page 47
Sampling
46
• If in doubt regarding sampling procedures, contact your diagnostic
laboratory
• Take samples from regions of tissue that include lesion margins
• It is better to submit too many samples to your diagnostician than
too few
Communicate directly with your animaldisposal services to provide them with theinformation they require for each animal to be picked up*:
• Age of animal• Cause of death• Time and date of death
*Some animal disposal services will not pick up an animal if the brain has been examined and/orremoved for diagnosis.
Guidelines for gaining the most information from a necropsy:
Large Necropsy Binder for PDF 4/22/02 10:26 AM Page 48
Intestinal sections• Size: 10-20 cm sections • Best, but not required, to tie off/close ends
Other tissues• Size: 4 cm cubes• Sample affected tissues • Sample tissues from other appropriate • organs
Brain*If indicated by history, place 1/2 brain inWhirlPakTM or other sealable container
Rumen content• If indicated by history• pH can be determined on site with pH strips
Shipping guidelines• Properly label and seal WhirlPaks • Use insulated container protected by • cardboard box • Include multiple frozen packs• Only freeze samples if necessary for • extended storage beyond 3 to 4 days
47
WhirlPak is a trademark of Nasco, Inc.
Sampling
Fresh Samples
*Some animal disposal services will not pick up an animal if the brain has been examined and/or removed for diagnosis.
Large Necropsy Binder for PDF 4/22/02 10:26 AM Page 49
18
Sampling
48
Intestinal sections • Size: multiple 2 to 3 cm sections • Do not tie off/close ends
Major organs and other tissues• Size: 1 cm thick or less• Include tissues as indicated by clinical
signs or gross lesions
Brain• If indicated by history, place 1/2 brain* in
WhirlPak or other sealable container
Proper packaging• Properly label each container• 10% buffered formalin solution• Formalin volume must be 10X tissue
volume• In most instances, multiple tissue
samples can be combined in a single container
Shipping guidelines• Seal in unbreakable containers• Double-bag the package contents with
absorbent material to ensure fluid containment• Include completed submission form for lab
(seal in separate plastic bag to keep dry)• Include complete case history• Include contact and billing information
(contact name, address, phone, fax, account number)
• If not shipping immediately, hold for two ormore days. Pour off majority of formalin prior to shipping.
Fixed Samples
*Some animal disposal services will not pick up an animal if the brain has been examined and/or removed for diagnosis.
Large Necropsy Binder for PDF 4/22/02 10:27 AM Page 50
15
Acknowledgements
49
Elanco Animal Health respectfully thanks the following individuals for their professional contributions to this project:
Bob Glock, DVM, PhDRoger Panciera, DVM, PhD
Dan Scruggs, DVM, PhDTed Clark, DVM, MVSc, Canada
Large Necropsy Binder for PDF 4/22/02 10:27 AM Page 51
50
This practical necropsy guide is brought to you by Elanco Animal Health.
Elanco and the diagonal color bar are trademarks of Eli Lilly and Company. Micotil® is a trademark for Elanco’s brand of tilmicosin. Tylan® is a trademark for Elanco’s brandof tylosin. Rumensin® is a trademark for Elanco’s brand of monensin sodium.
TMTMTMTM
Large Necropsy Binder for PDF 4/22/02 10:27 AM Page 52
Large Necropsy Binder for PDF 4/22/02 9:46 AM Page 1