Necropsy of Mammals

(See also Necropsy of Birds (Techniques Overview))

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• Post mortem examination (i.e. necropsy) is an extremely valuable tool in disease investigation and management. It is important to approach each carcass with an open mind, not assuming that the cause of death is known, even if there are obvious external lesions or a known on-going disease problem.
• Before starting a necropsy, consider whether the skin or skeleton is important for museum-based studies. If it is, a cosmetic post mortem is required. (see D257 - full text available for a description)
• Reasons for performing a post mortem examination include "finding the cause of death, confirming a diagnosis, investigating unsuccessful therapy, increasing knowledge" (D91.4.w1) and for the detection of sub-clinical disease.
  • Post mortem examination is particularly important for animals which die in quarantine in preparation for introduction to a collection, translocation or reintroduction program. 
• Post mortem examinations may be performed in the field or laboratory; by the case clinician or by a specialist pathologist, dependent on circumstances.
  • Where the gross post mortem is performed by an individual other than the pathologist who will perform the further examinations on samples provided, communication between the two parties is essential to ensure that optimal samples are taken (tissue type, volume/ weight, storage, transport, temperature etc.).
  • Inadequate or incorrect sample taking may reduce the likelihood of reaching an accurate diagnosis.
  • Forensic post mortems for legal investigation should be performed by an experienced wildlife pathologist, since the credentials of the pathologist will be assessed as part of the case. (J1.32.w7)
• Similar protocols should be used for the post-mortem examination of domestic, free-ranging or captive wild mammals.
• Post-mortem examination should be conducted in good daylight whenever possible. (D286.2.w2)
• If possible, findings should be dictated during the examination, or, as an alternative, noted down at the time of the examination. (D286.2.w2)
• When performing a necropsy or post mortem examination, it is important to:

• first consider the history of the animal (where available). Note the reported clinical signs, treatment, diagnostic tests, possible differential diagnoses, number of animals involved, etc. Communication between the pathologist and the case clinician, where available, is recommended.
• consider recent and historical disease problems in the collection (captive animal), region (free-ranging), in-contact domestic animal and human populations. 
• examine the site where the carcass was found if possible (e.g. evidence of agonal movements, convulsions disturbing the local area; piles of faeces and urine around the hindquarters suggestive of prolonged recumbency).
• have a systematic approach, whether head-to-tail, system by system (digestive system, respiratory system etc.), or any other.
• recognize the normal anatomy, normal appearance of organs/tissues and anatomical variation between species.
• have knowledge of seasonal differences in the body condition and reproductive system which are normal for the species under examination.
• have knowledge of the expected variations between individuals of the same species dependent on whether they are captive or free-ranging. (e.g. obese body condition may be seen in captive animals but is unlikely in free-ranging individuals; ectoparasite and endoparasite burdens may be expected to be greater in free-ranging wild animals than those under captive management.)
• have knowledge of the method, route and time of euthanasia if performed.
• have knowledge of potential artefactual findings e.g. hypostatic congestion (pooling of blood in organs under the effects of gravity which can be mistaken for pathological congestion), barbiturate crystals from euthanasia solution which can be mistaken for gout (See: Gout in Waterfowl (Miscellaneous Disease)), pseudo-prolapse of the anus or vagina as a result of increased pressure within the abdomen caused by gas production after death.) 
• accurately describe lesions/abnormalities.
• record both positive and negative findings.
• keep accurate records, including a unique identifying number for each carcass and for samples from that carcass.
• keep detailed notes on all findings and procedures for forensic post mortems, written in non-technical language wherever possible, for use in court. (J1.32.w7)
• avoid the use of non-standard abbreviations in permanent records.
• take photographs (include case identification details) for animal identification and illustration of gross pathology, particularly if the case may be involved in a prosecution enquiry. (J1.32.w7)
• preserve samples (tissues, parasites etc.) for further testing and future reference/research. 
  • A full spectrum of samples should be taken, where possible, at the initial examination if possible and stored appropriately. 
  • Further investigations, at first, may be directed at the samples thought most likely to be important in revealing the cause of death. However, if further samples are needed subsequently, the full spectrum are available in store.
  • Where time or financial constraints limit sample taking, a short list of standard tissues should be sampled, in addition to those with apparent gross pathology. 
  • In some circumstances it may be advisable to keep the entire carcass for a period following the post-mortem examination, refrigerated in the short term and frozen in the long term, to provide samples in the future if required.
• consult the appropriate regional authority if a notifiable disease (e.g. Foot-and-Mouth Disease) is suspected before progressing with the post mortem examination, 
  • Consult the List A and List B of notifiable diseases made available by the Office International des Epizooties - World Organisation for Animal Health (See: Website Ref - W31 - Office International des Epizooties)

• Carcass location and body size may dictate whether transport to the laboratory facility for examination is possible, or whether the post mortem must be performed in the field.
• Where field post mortem examination is unavoidable, attention should be paid to the risk of spread of infection to wild or domestic animals through opening of the carcass and available methods for carcass disposal (e.g. pit, cremation).
• Autolysis of the organs occurs with variable speed; the adrenal medullae, gastro-intestinal mucosa, pancreas, liver, kidney and central nervous system develop autolytic changes particularly quickly.
• Post mortem examination should be performed as quickly as possible after death has occurred and has been confirmed. However this may not always be possible, and carcass cooling to slow the rate of autolysis should be practised. 
  • Some authors suggest soaking of the fur in cold water with a small amount of detergent to aid in wetting of the skin.
  • The carcass should be placed within a sealed plastic bag, clearly labelled, with excess air removed, and be refrigerated if its body size allows.
  • Carcasses preferably should be refrigerated while awaiting examination. (B10.3.w18)
    • Where sufficiently large refrigeration facilities are unavailable, the carcass should be moved to as cool an area as is available.
  • With very large mammals, cooling of central organs will not occur sufficiently quickly to prevent autolysis; priority should be given to performing the post mortem as soon as possible; opening the abdomen may help lower the core temperature as quickly as possible.
  • Where post mortem examination must be delayed until 72-96 hours after death, the carcass should be refrigerated only. However if the examination must be delayed over 96 hours post mortem, it is recommended to freeze the carcass immediately.
• When transporting a carcass or pathological sample to a laboratory for analysis, attention should be paid to temperature control in transit. Insulated containers should be chosen, ice packing of frozen samples may be used and times when postal delays may be expected should be avoided (e.g. weekend, public holidays, strikes).
  • Local regulations governing the postage of pathological samples should be consulted (labelling, courier, container type etc.)
• In the event of a die-off (mass mortality event) it is important to examine fresh carcasses of a number of individuals, representative of the range of species affected and the ages of individuals affected, and to remember that more than one disease process may be acting at any one time and that the major cause(s) of death may change during a prolonged die-off.
• The results of the post mortem examination should be used in conjunction with the history of the mammal or mammals and assessment of the environment to help determine their significance and recommended future action.  
• In areas where rabies infection (See: Rabies) is enzootic, all mammals found dead, and particularly those with a clinical history of abnormal behaviour or neurological signs, should be carefully examined and considered as potentially infected until proven otherwise. (See: Human Health Considerations) 
• Suspect cases of sudden death should have peripheral blood smears taken to exclude anthrax infection (See: Anthrax) as a differential before the carcass is opened. Bloody discharges should direct the examiners' attention to the need to exclude anthrax infection before continuing with the examination. Dependent on region, specialist veterinary staff may be legally required to carry out the anthrax testing process.
  • Samples should be taken by nicking the dependent ear or from the coronary band. 
  • In wild equids (Equidae - Horses (Family) - horses and zebras), wild pigs (Suidae - Pigs (Family)) and carnivores (Carnivora - Carnivores (Order)), anthrax bacilli may not be present within the blood, therefore examination of a smear made from the cut surface of a lymph node (usually submandibular) is recommended in addition.
  • Tissue and blood smears should first be air dried and then be fixed in methanol.
  • Staining should be performed for two minutes with polychrome methylene blue, or Giemsa stain.
  • Samples should be examined under oil immersion microscopy for evidence of anthrax bacilli.
  • If anthrax infection is confirmed, careful attention must be paid to quick and effective carcass disposal. Regional authorities responsible for disease control should be notified and action taken as appropriate.
  • If anthrax infection is excluded, the post mortem examination should proceed.

  (B411)

• Estimation of time of death is not as widely a developed skill in wildlife as with human pathology; forensic entomology has not been used extensively in wildlife cases to date. (J1.32.w7)

• Detailed knowledge of ballistics (shot gun, air gun, arrow) and the typical wounds that they cause is useful, particularly for forensic post mortem examination. (J1.32.w7)

• Knowledge of the species of common predators for the animal under post mortem examination in that region is useful. An understanding of the distribution of the wounds that they typically inflict can be a useful aid for identification of cause of death or scavenging. (J1.32.w7)

• Note: If poisoning (e.g. plant poisoning) is suspected, the pathologist should be informed of this suspicion before the necropsy is carried out. (P6.4.w1)

• For information on carrying out a Cosmetic Post Mortem, to enable the skin and skeleton to be used for museum-based studies see: Cosmetic Post Mortem

(B10.3.w18, B127, B273, B411, B433, J1.32.w7, P24.327.w13, D91.4.w1, D257 - full text available, V.w26)

• Post mortem examinations may be performed on hedgehogs which have been found dead in the wild, those which have died shortly after presentation as a casualty, those which have died after treatment and a significant period in care, and those which are found dead shortly after release.
  • Consideration should be made as to whether the hedgehog has a recent history of free-ranging or captive management.
  • Certain conditions are more likely to develop after a period in captivity e.g. obesity, possible dental disease (See: Hedgehog Dental Disease)
• Use the season, age and sex of the hedgehog to guide investigation to the most probable causes of death.
  • e.g. starvation or hypothermia during the winter. (See: Starvation), burns during November close to Guy Fawkes night (bonfire night) in the UK. (See: Burns and Smoke Inhalation)
• When found dead in the wild, use study of the local habitat and hazards to suggest possible causes of death. e.g. roads, ponds, cattle grids. (See: Garden Management for Hedgehogs (Erinaceus europaeus))
• Ensure knowledge of the normal anatomy of the hedgehog. (See: Erinaceus europaeus - West European Hedgehog) 
• Knowledge of the marked variation in hedgehog body systems with season is required:
  • Seasonal variation in body weight, condition and fat deposits; particularly before and after hibernation. (See: West European hedgehog - Appearance-Morphology- Measurement and Weight, )
  • Seasonal variation in the male reproductive system with significant growth in the accessory sex glands in the breeding season with regression to inactivity in the autumn. (See: West European hedgehog - Detailed Anatomy Notes (Literature Reports) and West European hedgehog - Life Stages (Literature Reports) - Male Seasonal Variation)
• Hedgehogs are susceptible to natural infection with Foot-and-Mouth Disease, a notifiable disease. Where infection is suspected, the appropriate regional authorities must be contacted. (See: Foot-and-Mouth Disease)
• Arranging a hedgehog into a spread-eagled position immediately after death (i.e. before rigor mortis sets in) may be useful if a post mortem examination is to be carried out. (B337.6.w6) 

• Necropsy of an elephant "is a laborious task." (D286.Intro.w9)
• The constraints associated to the medical management of diseases in elephants are also applicable to the post mortem examination. (J359.7.w2)
• The opportunity to perform the post mortem examination before the autolytic changes begin is rare, particularly in free-ranging elephants. (J359.7.w2)
• If necropsy is to be delayed, consider covering the carcass with ice. (D292)
• Elephant necropsy should not be attempted by a single person; at least two assistants are required (i.e. a minimum team of three people). (P80.1.w1)
• The autopsy should be conducted systematically by a team of experts, ideally a pathologist, microbiologist and parasitologist along with skilled personnel to assist in the cutting and opening of the body, with the objective of making a specific disease diagnosis. (J359.7.w2)
• Assigning specific tasks to each of the necropsy team members is recommended. (B450.B.w28, D292)
  • It may be useful to designate a media liaison to act as spokesperson for enquiries from the media. (D292)
• Access to a clinical history and medical management of the elephant is a very valuable tool to achieve the post mortem objective of making a specific disease diagnosis. (J359.7.w2)
• Always consider the animal's past clinical history and treatments given, as well as the recent signs from physical examination, diagnosis made, treatment and the manner of its death. (D286.2.w2)
• Necropsy should always be attempted; it is acknowledged that it may not be possible to gather much useful information if the carcass is already decomposed. Decomposition starts quickly, particularly in hot weather. (D286.Intro.w9)
• In the field, approach a "dead" elephant which is in lateral recumbency carefully: it may be asleep and wake and attack when approached. If vultures are present, it is probably dead. (B411.IV.w4, P80.1.w1)

ALWAYS CONSIDER:

• Anthrax: DO NOT conduct a post mortem examination if anthrax is suspected. (B101, B336.67.w67, J64.21.w21)
  • Prior to starting the examination, make a blood smear and examine it to check for anthrax. (D286.2.w2)
• Mammalian Tuberculosis.
  • Search intensely for TB lesions during any elephant necropsy, even if the circumstances of death or euthanasia do not give any reason to suspect TB. (D292 - FULL TEXT INCLUDED)
  • Open the thoracic cavity last; this should be carried out by personnel wearing appropriate personal protective equipment such as hepa-filter masks. (D292)
• Herpesvirus Infection in Elephants For information on taking and sending samples, see:
  • D289 - Instructions for Elephant Endotheliotropic Herpesvirus (EEHV) Sample Submission - FULL TEXT INCLUDED

Requested measurements to be taken and tissues/features to be looked for, as well as information on samples to be taken for TB and EEHV are provided in: D293 - Elephant Research And Tissue Request Protocol

• Chapter 2 - B36 Field Manual of Wildlife Diseases - Specimen Collection and Preservation
• Chapter 3 - B36 Field Manual of Wildlife Diseases - Specimen shipment
• Elephant Research And Tissue Request Protocol
• D292 - Elephant Necropsy Protocol (Elephas maximus and Loxodonta africana) [includes details of checking and sampling for TB in elephant necropsies]
• D 289 - Instructions for Elephant Endotheliotropic Herpesvirus (EEHV) Sample Submission
• D303 - Guidelines for the control of tuberculosis in elephants 2003 [provides information on laboratories performing diagnostic tests for TB]

• Laboratory post mortem facilities should be housed in a separate room to the clinical facilities and should be easily cleaned, with adequate water supply and draining floors. 
  • Requirements for air exchange systems, fume cupboards etc. will vary according to the taxa under examination and, as such, the pathogen classes which are likely to be encountered.
• Suitable preventive clothing (See: Human Health Considerations)
• Weighing scales and measuring devices (tape, calipers) should be available with a level of accuracy and range appropriate for the mammal under investigation.
• Suitable dissection instruments should be available in the laboratory or the field:
  • Two suggested equipment lists for post mortem examination in the field include: 1) a curved knife for skinning; a straight, pointed knife for dissecting; a pair each of 25 cm rat-toothed forceps, 15 cm pointed forceps and 15 cm dissecting scissors; a sterile scalpel and blades; an enterotome; a bone saw; a large pair of bone forceps or bone-cutting shears; an axe; a sharpening stone and steel; a spring balance to weight up to 10 kg; a block and tackle; some nylon rope; and a small gas or alcohol burner for sterilising instruments. (B411.I.w1); 2) "knife, sharpening steel, forceps, scalpel and blades, small (hack) saw, disposable rubber gloves, rubber apron, small butane torch or alcohol lamp, matches, sterile syringes and needles, sterile swabs with transport media." (B127)
  • Dissection equipment should be clearly marked and kept solely for the purpose.
  • Equipment should be cleaned and sterilised following use.
  • Size of equipment should be tailored to the carcass size; ophthalmology instruments, hand lens and dissecting microscopes may be useful for small mammals where available.
  • All non-disposable cutting instruments should be kept sharp.
• Suitable sample collection equipment and disposables should be available in the laboratory or the field:
  • An equipment list for specimen collection in the field includes: sterile disposable 5 ml syringes and sterile needles (20 gauge); culture tubes with sterile swabs; microscope slides in box; sterile Universal bottles; sterile blood tubes; plastic bags with closure tops (Whirlpack or Ziploc type); heavy duty plastic sealing tape; 300 mL wide mouthed glass and plastic jars; a measuring tape or ruler rubber or plastic gloves; aluminium foil; a rabies kit (World Health Organisation (WHO)) (or a drinking straw in a small jar of buffered glycerine); labels, string and a waterproof marker pen or pencil. (B411.I.w1)
  • Microscope, clean slides and cover slips.
  • Sterile swabs and transport media.
  • Gas source for heating metal blade to sear surface of an organ before sampling for microbiology.
• Suitable fixation medium should be available in the laboratory or the field including 10% neutral buffered formalin, 70% alcohol for parasites, 100% acetone for cytology (danger flammable!), normal saline.
• Stain kits for cytological, bacteriological and fungal examinations (Gram, Ziehl-Nielsen, Diff-Quick^®, Hemacolor^®, Lactophenol blue, etc.). 

(B273, B411.I.w1, P24.327.w13, D91.4.w1, V.w26)

• Small dissecting instruments may be useful, particularly for post mortem examination of hoglets.
• Accurate electronic scales and calipers are required for biometric and weighing measurements.

• To move, manipulate or transport a elephant carcass a mechanical crane or a tow truck and chains may been used. (B450.B.w28, J359.7.w2)
• Chains and a tow truck may be sufficient for movement a short distance; (D292)
• A truck with a hoist is required to move the carcass to a remote location (placing it on a flatbed trailer may make this task easier). (D292)
  • If moving on a flatbed trailer, strap the elephant to the trailer and cover with a tarpaulin. (D292)
• It is important to check that the vehicle will handle the elephant's weight. (B450.B.w28, D292)
  • (Allow 2,300 - 3,700 kg for a female Elephas maximus - Asian Elephant, 3,700 - 4,500 kg for a male Elephas maximus - Asian Elephant, 2,300 - 4,000 for a female Loxodonta africana - African Elephant, 4,100 - 5,000 for a male Loxodonta africana - African Elephant. (D292)
  • Information on normal body weights in elephants is provided in:
    • Elephas maximus - Asian Elephant
      • See: Asian Elephant Elephas maximus - Appearance-Morphology- Measurement and Weight (Literature Reports)
    • Loxodonta africana - African Elephant
      • See: African Elephant Loxodonta africana - Appearance-Morphology- Measurement and Weight (Literature Reports)
    • Loxodonta cyclotis - Forest Elephant
      • See: Forest Elephant Loxodonta cyclotis - Appearance-Morphology- Measurement and Weight (Literature Reports)
• If the transportation of the carcass is delayed, the animal body should be covered with ice. (B450.B.w28, D292)
• A recommended equipment check list includes: (B450.B.w28)
  • Large animal necropsy instruments, including large knives, scalpel handles and scalpel blades, forceps, iron spatula, surgical scissors. 
  • Retractors of different sizes and shapes.
  • Sterile instrument for culture samples.
  • 10% neutral buffered formalin.
  • 4% glutaraldehyde.
  • Containers for sample collection.
  • Culture swabs and universal pots for urine.
  • Serum tubes for blood and urine collection.
  • Aluminum foil and plastic bags for freezing tissue samples.
  • Labels and waterproof marker pens.
  • Scales.
  • Tape measure, at least 2m long.
  • Chainsaw and axe (to cut through the skull); both a large and a small axe. 
  • Hammers, chisels, hand saws and hack-saws.
  • Hoist and/or crane.
  • Ropes.
  • Crow-bar.
  • Carts on rollers to move body parts.
  • Coveralls, boots, gloves, caps, protective eye and head gear.
  • Surgical masks approved for TB exposure, for all personnel involved in the necropsy.
  • Access to water with a hose.
  • First aid kit.
  • Camera and appropriate accessories (e.g. film, batteries.)
  • Emergency lamps/generator; torches (flashlights). (D286.2.w2)

  (B450.B.w28, D286.2.w2, D292)

• In the field, recommended equipment includes: (B411.IV.w4)

  "1. Four or five large butcher knives and sharpening steel or other sharpening device
  2. Several robust meat hooks
  3. A large saw, suitable for sectioning some of the massive bones
  4. A large axe
  5. A shovel
  7. A block and tackle where possible
  8. A wheelbarrow
  9. Adequate water
  10.Large PVC tray/containers and cutting boards
  11.Thick ropes or chains
  12.A portable gantry, where possible
  13.A metal detector to locate bullets in poached animals."

• Where a gantry and block and tackle are not available, a 4x4 drive vehicle with ropes and a tree fork to use as an elevation point may be able to substitute. (B411.IV.w4)
• Note: A chain saw is useful, but tends to get blocked up with sinews and fat. (B411.IV.w4)
• Camera: particularly if litigation is a possibility. (B411.IV.w4)
• Magnifying glass. (D286.2.w2)
• Torch (flashlight). (D286.2.w2)

Another list includes knives and sharpening steel, hooks, both saw and chain saw, an axe, a shovel, block and tackle, a wheel barrow, rope or chain and an adequate supply of water. (P80.1.w1)

Requested measurements to be taken and tissues/features to be looked for, as well as information on samples to be taken for TB and EEHV are provided in: D 293 - Elephant Research And Tissue Request Protocol

• Chapter 2 - B36 Field Manual of Wildlife Diseases - Specimen Collection and Preservation
• Chapter 3 - B36 Field Manual of Wildlife Diseases - Specimen shipment

• Record the sex and estimate age. Classification as a neonate/ infant/ juvenile/ adult/ geriatric may be useful.
• Record any identifying numbers e.g. tattoo, tags, microchip numbers etc. Retain any physical markers for future reference e.g. radio-transmitters, tags.
• Record any characteristic features e.g. characteristic scars or colour marks, coat colour (e.g. albino, leucistic, melanistic).
• Examine the inside of the container/wrappings that the carcass has been presented in, noting contaminants (e.g. mud, oil) and possible external parasites such as fleas, lice or mites which may have left the host. Presence of maggots within the wrappings may indicate significant carcass decomposition but should alert the examiner to search for lesions of fly strike (See: Myiasis (with special reference to Waterfowl) (Parasitic Disease))
• Weigh the carcass . Dry weight should be taken where possible to minimise error. Where the carcass is presented wet, this should be noted for future reference to allow recognition of potential bias.
• Biometric measurements: A range of biometric measurements should be taken using graduated calipers. The accuracy and units of measurement should be clearly noted. Examples include tibial length, crown-rump length. Description of the exact biometric parameter used should be available to avoid confusion in the future when trying to  reproduce the measurement and compare between individuals of the same species.
• Body condition - use a combination of subjective and objective measurements of body condition where possible. 
  • Subjective scoring systems can be developed using indices based on muscle bulk, amount of subcutaneous and visceral fat deposits. 
  • Objective scores can be developed, perhaps by creating indices of parametric measurement to body mass.
• Radiography may be indicated to detect e.g. fractures, radio dense foreign bodies, air gun or shot gun pellets, metabolic bone disease.
• Examine the external surface of the carcass . Note whether the carcass is fresh or decomposed; whether it has been refrigerated or frozen; also whether it is intact or scavenged, and if scavenged to what degree. 
  • Estimate time of death where unknown.
  • Autolysis will be accelerated where the temperature of the animal was increased at the time of death e.g. heat stroke, lightning strike.
  • Differentiate gas production in the gastro-intestinal tract post mortem with pre mortem 'bloat'.
  • Bile staining of tissues adjacent to the gall bladder can be seen in carcasses as post mortem change.

(B411.II.w2, V.w26, P24.327.w13)

Sexing hedgehogs

• In the adult male, or boar, the prominent penis sheath (prepuce) is positioned in the midline close to the navel.(B262.2.w2, B260.1.w1, B228.2.w2, B254.14.w14); about five centimetres (two inches) cranial to the anus.(B254.14.w14) 
• Identification of the sex of new-born hedgehogs can be challenging.(B228.2.w2) The prepuce of the male is positioned close to the anus in the infant and gradually migrates forward towards the navel as the animal grows.(B228.2.w2)
• Care should be taken not to confuse the umbilicus of the neonatal hedgehog with the prepuce of the infant male. (B228.2.w2)
• In the adult female, or sow, the anus and vagina are positioned close together (approximately 1 cm apart).(B262.2.w2, B228.2.w2, B254.14.w14)  
• The testes of the hedgehog are not externally palpable or visible within a scrotum but instead are positioned inside the abdomen.(B228.2.w2, B142)
  • For further information see: West European hedgehog - Detailed Anatomy Notes (Literature Reports))

Age determination in hedgehogs

• The appearance of the spines, whether the eyes and ears are closed or open, eruption of the teeth, ability to curl into a ball, independence form the nest, etc. can be used for age estimation of infants and juvenile hedgehogs.
  • (See: West European hedgehog - Life Stages (Literature Reports) - Neonatal development)
• Body weight is too variable a parameter for use in age estimation. (B254.24.w24)
• Several techniques for age estimation have been described including examination of the growth rings in the cut surface of the jaw bone and examination of the degree of growth plate fusion.
  • For further information see: West European hedgehog - Life Stages (Literature Reports) Longevity/Mortality - Age Estimation Techniques)

Markers / Appearance

• Notes should be taken of any marking devices found on the hedgehog. e.g. radio-transmitter, shrunk on plastic markers, etc.
  • Every effort should be made to contact the organisation known, or though likely, to be undertaking a hedgehog study using such markers.
  • Feedback from marked hedgehogs may provide useful information for post-release monitoring studies, etc.
• Occasional reports of hedgehogs with unusual general appearance occur. These include true albinos, blond and spineless individuals. (B262.2.w2)
• True albino hedgehogs are seen with pink nose and feet. White hedgehogs with black nose and eyes are also observed.(B142) 
• Melanistic colour variant hedgehogs with a completely black coat have never been reported.(B260.1.w1, B254.6.w6, B228.1.w1, B142)
  • For further information see: West European hedgehog - Appearance- Morphology- Skin-Coat-Pelage (Literature Reports))

Weight

• The degree of seasonal variation in body weight, condition and fat deposits; particularly before and after hibernation should be understood. 
  • (See: West European hedgehog - Appearance-Morphology- Measurement and Weight (Literature Reports))
• A scoring system based on the presence of subcutaneous fat deposits and thigh muscle bulk can be used as subjective indicators of body condition. The following scheme is based on these indicators: "1 thin, no subcutaneous fat and wasted musculature; 2 moderate, no subcutaneous fat but good muscle thickness; 3 good, some subcutaneous fat; 4 fat, a thick covering of subcutaneous fat." (J3.138.w2)

• Take pictures, particularly if litigation is a possibility.  (B411.IV.w4, P80.1.w1)
• Check for signs of putrefaction. (D286.2.w2)
• Note the position of the carcass. (D286.2.w2)
  • If the positioning is awkward and a leg appears possibly broken, it is important to check that leg carefully; a fracture causing immobility can be fatal. (P80.1.w1)
• TAKE A BLOOD SMEAR BEFORE OPENING THE CARCASS, and examine it to check for anthrax. (D286.2.w2, P80.1.w1)

Requested measurements to be taken and tissues/features to be looked for, as well as information on samples to be taken for TB and EEHV are provided in: D293 - Elephant Research And Tissue Request Protocol

Sex and genitalia

• Identify the animal's sex. (D286.2.w2, P80.1.w1)
  • In neonates, the distance from the umbilicus to the genital orifice is about four finger-widths in males, eight in females. (B411.IV.w4)
  • The clitoris of the female is pink, the penis of the male is blueish grey. (B411.IV.w4)
• Examine the mammary glands in females, the prepuce and penis in males. (D286.2.w2)
  • See: Priapism in Elephants

Body measurements

• Body measurements can be recorded before euthanasia, if it is planned, or as soon after death as possible. (B450.B.w28, D292)
• All measurements should be taken in a straight line, unless specifically indicated otherwise. (B450.B.w28)

Weight

• Weight should be recorded when possible.

Elephas maximus - Asian Elephant

• See: Asian Elephant Elephas maximus - Appearance-Morphology- Measurement and Weight (Literature Reports)  

Loxodonta africana - African Elephant

• See: African Elephant Loxodonta africana - Appearance-Morphology- Measurement and Weight (Literature Reports)

Loxodonta cyclotis - Forest Elephant

• See: Forest Elephant Loxodonta cyclotis - Appearance-Morphology- Measurement and Weight (Literature Reports)

Body condition

• This should be assessed. (B411.IV.w4, P80.1.w1)
• Temporal depression, protrusion of the ribs or scapular spines, and a sunken flank (deep lumbar depression) may indicate poor condition. (B455.w1, B411.IV.w4, D286.2.w2, P80.1.w1)
• Very loose skin, with a "baggy pants" appearance of the skin over the hind quarters also indicates poor condition.  (B411.IV.w4, D286.2.w2)
• A body score for Elephas maximus - Asian Elephant has been developed. (B455.w1)

Time of death

• This may be estimated using a combination of findings: (D286.2.w2)
  • Rigor mortis usually appears within one to four hours and lasts for 16 - 18 hours. However, it may start immediately or be delayed by four to 24 hours, and may pass off within three hours or remain for as long as 48 hours. (D286.2.w2)
  • Decomposition usually starts in six to 36 hors but is affected by the temperature and humidity. With advanced decomposition, the muscles become pale red and watery. (D286.2.w2)

Excreta and secretions

• Collect a fresh dropping, or a faecal ball from the rectum; examine for the consistency of the food particles. (D286.2.w2, P80.1.w1)

  • Coarse, poorly digested food particles in the faeces may be found in elephants with tooth problems. (B10.34.w42, B23.79A.w11, P1.1982.w1, P80.1.w1) See: Molar Maldevelopment and Malocclusion in Elephants

Presence of penetrating wounds

• These may be from bullets or tusks. (P80.1.w1)

In neonates

• Examine the umbilicus. (D286.2.w2)

Measurements

• Record the bear's weight.
• The total body length, tail length, hindfoot length (with and without claws) and ear length should be recorded.

External genitalia

Abnormalities of the external genitalia reported in bears include:

• Clitoriditis in Bears
• Cryptorchidism in Bears
• Hypospadias in a Bear
• Pseudohermaphroditism in Bears

Body condition

• Body condition in bears can be described as follows:
  • Poor condition: It is easy to feel the bear's hip bones, shoulder blades, spine and ribs; the bear looks unhealthy, like a skeleton with skin stretched over it;
  • Fair condition: The bear appears thin but not unhealthy; the bear's hip bones, shoulder blades, spine and ribs are easily palpable, but not prominent;
  • Good condition: The bear appears healthy but not extremely fat; it is difficult to feel the bear's hips, shoulder blades, spine and ribs;
  • Excellent condition: The bear appears extremely fat and healthy; the bones of the bear's hips, shoulder blades, spine and ribs cannot be palpated.

  (D249.w10)

• A five-point scoring system for polar bears (provided by the Polar Bear Specialist Group) is: (D251.5.w5)
  • 1: pelvis and scapulae protruding, ribs easily palpated, a deep hollow notable between the pelvis and last rib, showing virtually no fat.
  • 2: pelvis easily palpable, ribs palpable but with some muscle covering; an obvious hollow is present between the pelvis and the last rib, but this is softer than in (1).
  • 3: Body fully fleshed out, with obvious fat present over the pelvis and shoulders, the ribs are less obvious and there is no hollow between the pelvis and the last rib.
  • 4: the bear has a rounded or blocky appearance and is well fleshed over all bony areas, with obvious fat over the rump and shoulders.
  • 5: the bear's legs appear too short for the body; there are rolls of fat on the neck and lower shoulders.

  (D251.5.w5)

• Body weight is reduced following hibernation; some wild bears starve in the period following emergence from hibernation. See: Starvation in Waterfowl and Seabirds (with notes on Hedgehogs and Bears)

Wounds etc.

Note any localised infections or injuries:

• Abscess in Bears
• Bacterial Wound Infection and Cellulitis in Bears (Bacterial Disease Summary)
• Lacerations & Punctures, including bite wounds (with special reference to Waterfowl, UK Wildlife and Bears) 
• Navel Infection in Bears
• Umbilical Hernia in Bears

• Chapter 2 - B36 Field Manual of Wildlife Diseases - Specimen Collection and Preservation
• Chapter 3 - B36 Field Manual of Wildlife Diseases - Specimen shipment
• D293 - Elephant Research And Tissue Request Protocol

• Examine the eyes, ears, nostrils (external nares) and mouth for evidence of haemorrhage, discharge, external parasites, maggots (See: Myiasis), abnormal growths, foreign bodies, other lesions etc.
  • Fatalities following acute plant poisoning may still have remnants of the plant material within their mouths.
  • Examine the eyes carefully for evidence of opacity or long standing injury which may have compromised vision. Free-ranging predators may lose condition and potentially starve if they rely on acute vision to catch prey.
• Mucous membrane colour in the mouth and eyes should be assessed for evidence of jaundice or pallor (suggestive of blood loss or profound anaemia).
• Examine the condition of the lips, oral mucosa, soft / hard palate and tongue for lesions such as ulcers, growths or developmental abnormalities (e.g. cleft palate).
• Cut through the oral commissures to allow adequate examination right to the back of the oral cavity.
• For more thorough examination, continue the incisions to allow disarticulation of the lower jaw.
  • This will enable full inspection of the nasopharyngeal area, tonsils, retropharyngeal and parotid lymph nodes, as required.
• The teeth should be examined for evidence of tooth loss, abnormal or excessive wear (attrition), gingivitis, periodontal disease, tartar accumulation etc.
  • Full dental formula should be recorded.
• Remove the skin from the skull and the temporal muscles as necessary.
  • Examine the subcutaneous tissues and skull table for evidence of trauma, bruising, etc.
• Section the base of the auricular (ear) cartilages and examine the contents for evidence of discharge, inflammation, parasites etc.
• Sectioning of the skull for examination of the sinuses, turbinates or tympanic bullae may be performed if required, given specialist facilities.

Samples

• Tissue samples, swabs for culture and impression smears should be taken when tissues are first examined and before they become contaminated.  
• Tissue to be fixed for histopathology should be no more than 10 mm thick, and thinner if congested. 
• Samples for histopathology should not be frozen since this results in crystal formation and cell rupture.
• Samples for histopathology should be placed in at least ten times the volume of formalin fixative as the tissue.
• Eyes may be removed with care and fixed in a preservative preferred by the histopathologist, e.g. Bouin's or Zenkers solution.
• Collect external parasites in 70% ethanol for preservation and further identification as required.
• Appropriate chain of custody and sample labelling should be followed when dealing with legal cases.(J1.32.w7)

(B411.II.w2, B411.III.w3, P24.327.w13, D91.4.w1, V.w26)

• Closely examine the eyes, ears, mouth, and any wounds for evidence of fly eggs or maggots, particularly in the summer. (See: Myiasis)
• Check the jaw and hard palate for fractures and trauma which occur fairly frequently in hedgehogs, e.g. road traffic accident victims.
• Injuries to the nose which could have interfered with the ability to smell may be more important than damage to the eyes because the hedgehog relies principally on the senses of smell and hearing for food acquisition. (See: West European hedgehog - Feeding Behaviour (Literature Reports))
• Examine the external ear canals for evidence of mite infection. (See: Hedgehog Notoedres Mange))
• Full dental formula for the hedgehog is 3.1.3.3/2.1.2.3 (I3/2, C1/1, P3/2. M3/3).(B142)
  • For further information on dental morphology (See: West European hedgehog - Appearance-Morphology- Head and Neck (Literature Reports) - Dentition)
  • For further information on dental eruption times. (See: West European hedgehog - Life Stages (Literature Reports) - Neonatal development) 
• Carefully examine the teeth for evidence of gingivitis, tooth loss, periodontal disease, tartar accumulation. These findings may be more common in animals that have been in captivity on an artificial diet for some time. (See: Hedgehog Dental Disease)

• The head is usually removed from the body and the trunk and ears are cut, to facilitate the examination. (D292, J359.7.w2)
  • The head is severed from the body at the atlanto-occipital joint. (P80.1.w1)
  • A battery-operated reciprocating saw with replacable metal cutting blade is useful for entering the cranium. Otherwise, a chain saw together with a large axe and chisels are required. (D292)
  • To remove the brain, make three connecting cuts in the flattened triangle at the base of the skull, then use a curved crow bar to remove the bony plate in pieces. Note: there is a hazard to personnel from fragments when a chain saw is used. Appropriate personal protective equipment for the eyes, face and head should be worn. (D292)
  • After the skin and muscle have been reflected, a chain saw or axe can be used to make a sagittal section just above the eyes to reach the brain. (P80.1.w1)
  • A chain saw can be used to saw the head into two pieces. (P80.1.w1)
    • This is difficult and time-consuming. (P80.1.w1)
  • A hand saw or axe can be used to open up the middle ear. (P80.1.w1)
    • This is difficult and time-consuming. (P80.1.w1)

Gross examination of the head and neck includes examination of: (B450.B.w28)

• Nasal cavity and larynx. (B450.B.w28)
• Oral cavity: mouth, tongue, palatal pits, teeth and pharynx. (B450.B.w28)
  • Check for lesions in the mouth indicative of Foot-and-Mouth Disease (Note: Details of the disease in elephants are given on the page Foot-and-Mouth Disease - Editorial Overview of Disease Characteristics for specified SPECIES-TAXA). (D286.2.w2)
  • Eggs from bot flies may be found around the teeth and the base of the tusks. See: Bots in Elephants
  • The elephant's age can be estimated from the molars. (P80.1.w1)
• Trunk: any swelling, trophy or injury. 
  • The trunk can be removed from the head at the trunk's base by cutting above and between the tusks. (P80.1.w1)
• Tusks: look for a black spot at the tip, broken tips, longitudinal cracks, irregularities of the dentine. (P80.1.w1)
• Cervical trachea and oesophagus. (B450.B.w28) (see also the sections on the respiratory tract and gastro-intestinal tract)
• Sensory organs: eyes, ears, Jacobson's organ, temporal glands and proboscis. (B450.B.w28, B411.IV.w4)
  • Dissect the eyes from the orbits. (D286.2.w2)
  • Heavy discharge from the temporal glands may indicate severe stress before death (e.g. from pain or disease), but is normal in bulls in musth (these bulls will also have urine staining on the inside of the hind legs, and a rank smell). (B411.IV.w4, P80.1.w1)
• Endocrine system: pituitary gland, thyroid and parathyroid glands. (B450.B.w28)
• Nervous system: brain, meninges and cervical spinal cord. (B450.B.w28)

Diseases affecting the trunk of elephants include

• Flaccid Trunk Paralysis in African Elephants Loxodonta africana

• Trunk Paralysis (Non-Specific) in Elephants

• Trunk Wounds in Elephants

Diseases affecting the mouth and tusks of elephants include

• Bacterial Tusk Infection in Elephants

• Foot-and-Mouth Disease - Editorial Overview of Disease Characteristics for specified SPECIES-TAXA

• Molar Maldevelopment and Malocclusion in Elephants

• Tusk Development Problems in Elephants

• Tusk Sulcus Infection in Elephants

• Tusk Injury in Elephants

Eye and ear diseases of elephants include

• Cataracts in Elephants

• Conjunctivitis in Elephants

• Ear Mites in Elephants

• Frostbite

• Iatrogenic Segmental Ear Gangrene in Elephants

• Keratitis and Corneal Ulceration in Elephants

• Miscellaneous Eye Lesions in Elephants

• Otitis Externa in Hedgehogs and Elephants

• Myiasis

Recommended tissue sampling (B450.B.w28)

• Gross lesions.
• Representative sections of the brain. (B450.B.w28)
• Pituitary gland, including dura. (B450.B.w28)
• Eyes. (B450.B.w28)
• Cross section of the tongue that include both mucosal surfaces. (B450.B.w28)
• Intact thyroid and parathyroid with a single transverse cut. (B450.B.w28)
• Section of thymus. (B450.B.w28)

Sampling for Mammalian Tuberculosis (with special reference to Badgers, Hedgehogs and Elephants)

• Open the whole length of the trunk and check for any plaques, nodules or suspicious lesions. Any found should be divided into two sections, one into formalin and sent for histopathology, the other deep frozen and sent for culture. (See: D292 - Elephant Necropsy Protocol (Elephas maximus and Loxodonta africana))

Requested measurements to be taken and tissues/features to be looked for, as well as information on samples to be taken for TB and EEHV are provided in: DD293 - Elephant Research And Tissue Request Protocol

Eyes

• Slightly sunken orbits may indicate dehydration. (J1.35.w5)
• Note any ocular lesions: Ocular Disease in Bears
  • Ocular nematodes have been detected in bears. See: Eyeworms in Bears
  • An inactive hyperpigmented chorioretinal scar in the tapetal region of the left eye, compatible with a healed blastomycotic chorioretinal granuloma, was noted in a bear with blastomycosis (Blastomycosis in Bears)
  • Temporary unilateral corneal opacity has been seen following canine adenovirus 1 infection (Infectious Canine Hepatitis (with special reference to Bears))
  • Ocular neoplasms reported in bears include squamous cell carcinoma, melanoma of the eyelid and myxoma of the palpebral conjunctiva. (B16.9.w9, P1.2002.w5) See: Neoplasia in Bears
  • One case of a grass awn penetrating the cornea of a bear cub has been observed. (J417.20.w1, V.w93)

Ears

• Lesions associated with biting insects may be found on the tips of the ears. See: Biting-Blood-sucking and Nuisance Flies Affecting Elephants and Bears
• Grass awns and other plant material have been found commonly in the external auditory canals of Pacific Northwest Ursus americanus - American black bear. (J417.20.w1, V.w93)

Mouth, external nares, throat

• Check the condition of the tongue, teeth, gums and tooth sockets, also the salivary glands, larynx, trachea, thyroid glands, thymus and lymph nodes. (D247.7.w7)
• Check the mouth and the throat for foreign bodies and dental disease. See: 
  • Choke in Elephants and Bears
  • Dental Disease in Bears
  • Oral Foreign Bodies in Hedgehogs and Bears
• Check the mouth of cubs for signs of Candidiasis in Waterfowl and Bears (with notes on Elephants)
• Examination of the tongue musculature (at least in Ursus americanus - American black bear) may detect the presence of Gonglyonema pulchrum nematodes. See: Gonglyonema pulchrum Infection in Bears

Skull, internal nasal chambers

• Abnormalities of the skull and facial bones have been see with cretinism, hydrocephalus and severe rickets. See:
  • Calcium-Vitamin D Metabolism Imbalance (with special reference to Hedgehogs, Elephants and Bears)
  • Cretinism in a Bear
  • Hydrocephalus in Bears
• The brain, pituitary and meninges, and the nasal cavity, maxillary and frontal sinuses should be examined. (D247.7.w7)
  • Examination of these will be restricted if a cosmetic necropsy is being carried out so the skull can be preserved for taxonomic research. (D247.7.w7)
  • Examination of the nasal chambers and sinuses may reveal the presence of fluid and flukes. See: Prouterina wescotti Infection in Bears
  • Look for any abnormalities of the brain vascular system. See: Cerebral Arteriosclerosis in a Bear

• Chapter 2 - B36 Field Manual of Wildlife Diseases - Specimen Collection and Preservation
• Chapter 3 - B36 Field Manual of Wildlife Diseases - Specimen shipment

• Note the general appearance of carcass pelage (fur, spines, whiskers (vibrissae)) - e.g. condition, wet, muddy, oiled, clean, bloody, moult. 
  • If contaminated, note extent and areas affected.
  • If in moult, note the extent and take into account the season.
  • Missing patches of fur should be correlated with wounds, parasites, history of pruritus (itching), entanglement etc.
  • Condition of the fur may indicate whether the animal was in good condition or a state of debility prior to death.
• Note any wounds present and characterise them in terms of age, size, location, degree of sepsis.
• Check for the presence of external parasites (ectoparasites)- fleas, lice, ticks, maggots etc. 
  • Note the species, numbers (accurate or approximate indication), distribution.
  • Particular attention should be paid to checking the predilection sites for external parasites e.g. armpits (axillae), groin, perineum, hoof clefts, eyes, ears etc.
• Systematically part the hair over multiple areas of the body to examine the skin, looking for lesions including bite wounds, papules, macules, pustules, comedones, furuncles etc.
• Examine all body orifices, including the anus, vulva, prepuce, cloaca, marsupium (pouch) as appropriate, for evidence of haemorrhage, discharge, parasites, maggots (see Myiasis), abnormal growths etc.
• The carcass must be turned over allowing a full examination to be performed over both sides of the body.
• Examine the perineum and hindquarters for evidence of faecal scouring suggestive of diarrhoea (scour).
• At the end of the post mortem, the skin should be removed from all of the carcass to allow complete examination of the subcutaneous layers.
  • Check for evidence of bruises, wounds, parasites, ballistic wounds, snake bites, burns, etc.

Samples

• Collect external parasites in 70% ethanol for preservation and further identification as required.
• Skin samples for further examination include collection and microscopic (or hand lens) examination of scurf, scale, hair pluckings, deep skin scrapes, Sellotape (clear sticky tap) impression smears, Woods lamp (UV) examination for dermatophytes, swab or sample for  microbiology (bacteriology, mycology), lesion sample for histopathology, lesion sample for virology.
• Tissue samples, swabs for culture and impression smears should be taken when tissues are first examined and before they become contaminated.  
• Tissue to be fixed for histopathology should be no more than 10mm thick, and thinner if congested. 
• Samples for histopathology should not be frozen since this results in crystal formation and cell rupture.
• Samples for histopathology should be placed in at least ten times the volume of formalin fixative as the tissue.
• Appropriate chain of custody and sample labelling should be followed when dealing with legal cases.

(B411.II.w2, B411.III.w3, P24.327.w13, D91.4.w1, V.w26)

• Closely examine the vulva, prepuce, perineum and any wounds for evidence of fly eggs or maggots, particularly in the summer. (See: Myiasis)
• Check all the spines and skin for evidence of wounds whose appearance may give an indication as to their cause:
  • Clean fresh lacerations, snout and limb amputations following strimmer injuries. (See: Lacerations & Punctures, including bite wounds)
  • Encircling snare-like wounds after being caught in plastic drink can trimmings or netting. (See: Foreign Body Entanglement & Snaring))
  • For information on prevention see: Garden Management for Hedgehogs (Erinaceus europaeus)
• Examine the spines for evidence of charring or burns, particularly in the autumn or if there is a history of garden fires in the area. (See: Burns)
• Examine between the spines for ectoparasites, particularly ticks (see: Tick Infection in Mammals) and fleas (see: Flea Infection in Mammals)).
  • Increased numbers of ectoparasites are often seen on hedgehogs which were debilitated prior to death.
• Check for evidence of scurf, scale and hair loss around the face, muzzle, ears, belly and 'skirt' (margin between the haired and spined areas).
  • Samples for dermatophyte culture and skin scrapings for parasitological investigation may be required for diagnosis.
  • See: Ringworm in Hedgehogs, Caparinia Mange of Hedgehogs
• Note any smells which may be associated with wounds, mite infection, other skin problems, or contamination. (B337.6.w6) 

• In wild elephants, check carefully for penetrating wounds, for example due to bullets, tusks. (B411.IV.w4, D286.2.w2, P80.1.w1) or (particularly in calves) mauling by a large carnivore. (D286.2.w2)
  • In captive elephants, check for injuries which may have been inflicted by mahouts. (D286.2.w2)
• Look for signs of dislocations or fractures. (D286.2.w2)
• Skinning of the carcass may be required if any penetrating wounds are present (Wounds in Elephants), or to detect subcutaneous abscesses (Subcutaneous Abscess in Elephants). (P80.1.w1)
• Check for external parasites such as fleas or ticks. (P80.1.w1) (Flea Infection in Mammals, Tick Infection)

• Burns and Smoke Inhalation (with special reference to Waterfowl, Hedgehogs and notes on Elephants)

• Dermatitis in Elephants

• Dermoid Cysts in Elephants

• Elephant Foot Fly Infection

• Epidermoid Cysts in Elephants

• Filariasis of Elephants

• Flea Infection in Mammals (with special reference to Hedgehogs and a note on Elephants)
• Foot-and-Mouth Disease
  • (Note: Details of the disease in elephants are given on the page Foot and Mouth Disease - Editorial Overview of Disease Characteristics for specified SPECIES-TAXA)

• Foot Wounds in Elephants

• Frostbite in Waterfowl (with notes on Elephants)

• Iatrogenic Segmental Ear Gangrene in Elephants

• Idiopathic Ventral Oedema in Elephants

• Ingrowing Nails in Elephants

• Herpesvirus Infection in Elephants