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Veterinary Forensic Pathology: Drowning and Bodies Recovered From Water
Article in Veterinary Pathology · February 2016
DOI: 10.1177/0300985815625757
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Veterinary Pathology OnlineFirst, published on February 29, 2016 as doi:10.1177/0300985815625757
Review
Veterinary Forensic Pathology: Drowning
and Bodies Recovered From Water
Veterinary Pathology
1-8
ª The Author(s) 2016
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DOI: 10.1177/0300985815625757
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B. J. McEwen 1 and J. Gerdin 2
Abstract
Determining the cause of death in animals recovered from bodies of water, swimming pools, or other water-containing vessels is
challenging. Animals recovered from water may or may not have drowned. The diagnosis of drowning is usually one of exclusion,
requiring information from the crime scene, recovery scene, the medical history or reliable witness accounts. While there are
characteristic macroscopic and microscopic lesions of drowning, none are specific and are dependent on the volume and tonicity
of the drowning medium. Beyond interpreting the postmortem findings, the court may ask pathologists to comment on the
behavioral and welfare implications of drowning. This requires an understanding of the drowning process, which is a complex
series of sequential, concurrent, and overlapping cardiorespiratory reflexes, electrolyte and blood gas abnormalities, aspiration,
physical exhaustion, and breathlessness eventually culminating in death. This review addresses the mechanisms, lesions, and
diagnostic issues associated with drowning in nonaquatic companion animals.
Keywords
accidents, animal welfare, anoxia, asphyxia, aspiration, drowning, forensic pathology, veterinary
Determining the cause of death in animals recovered from
bodies of water, swimming pools, or other water-containing
vessels is challenging. The key question is this: was the animal
alive when it entered the water? 60 The diagnosis of drowning is
usually one of exclusion, requiring information from the crime
scene, recovery scene, the medical history, or reliable witness
accounts. 14,67,71,77 Tides, currents, people, or other animals
may move the body from the original scene, and postmortem
changes due to submersion, injuries, or scavengers can introduce
artifacts and obscure lesions. Animals may be disposed of
in water following death due to other causes, or conversely,
may be removed from the water after drowning (Fig. 1).
The definition and terminology associated with drowning,
as with other types of asphyxia are varied. 5,75 Before 2002,
definitions were classified as ‘‘drowning’’ if fatal, or ‘‘neardrowning’’
if the patient survived even temporarily, and both
were divided into those cases in which aspiration of water was
present or absent. 5 In 2002, the definition of drowning and its
possible outcomes were decided by an international expert
committee of the World Health Organization (WHO):
‘‘Drowning is the process of experiencing respiratory impairment
from submersion/immersion in liquid’’ and ‘‘outcomes
are death, morbidity and no morbidity.’’ 5 The following terms
referring to drowning, described in depth by Idris et al, 32 are no
longer recommended: passive, silent, wet, dry, active, secondary
5,32 or near-drowning. 64 The revised terminology has been
applied in at least 1 review of canine drowning 28 and we recommend
that it be adopted by veterinary pathologists. Submersion
signifies that the entire body is under water, whereas
immersion refers to the body being partly covered with water,
although the airway must be immersed for drowning to occur. 32
The frequency of drowning in animals is unknown. An
estimated 388000 people drown annually and it is the third
leading cause of accidental death worldwide. 66 The peerreviewed
veterinary literature on accidental and nonaccidental
drowning in animals is scarce, 1,6,28,31,58,60 although the
topic is covered briefly in several veterinary forensic textbooks.
18,50,59 Accidents while in water including electrical
shock, entrapment, entanglement, and neurologic dysfunction
such as ataxia and epilepsy are reported in animals that have
drowned, or have been resuscitated following rescue from
water. 1,30 Experiments in which dogs or other animals were
drowned to determine physiological and biochemical
responses to various volumes, temperatures and salinity of
water or other liquids 2,3,8,11,17,26,27,53,55,57,72,73,82,83 provide
information into the drowning process. Because most of these
experiments were done between 20 and 200 years ago, the
lack of consideration for the welfare of animals used in these
experiments is often disturbing. Although we and others
1 Animal Health Laboratory, Laboratory Services Division, University of
Guelph, Guelph, Ontario, Canada
2 Antech Diagnostics, Hunt Valley, MD, USA
Corresponding Author:
B. J. McEwen, Animal Health Laboratory, Laboratory Services Division, University
of Guelph, Box 3612, Bldg 89, Guelph, Ontario, Canada, N1 H 6R8.
Email: bmcewen@uoguelph.ca
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2 Veterinary Pathology
Figure 1. Possible scenarios of bodies recovered from water.
recognize this, 60 useful information applicable to veterinary
forensic pathology can be gained from these experiments. The
objective of this paper is to review the mechanisms, lesions
and diagnostic issues associated with drowning in nonaquatic
companion animals.
The Process and Mechanism of Drowning
The drowning process is complex, involving sequential, concurrent
and overlapping cardiorespiratory reflexes, electrolyte
and blood gas abnormalities, aspiration and swallowing of
liquid, vomition, struggling, involuntary movements and physical
exhaustion, breathlessness, or ‘‘air-hunger’’ 4 eventually
culminating in death. 7 The central mechanism of drowning is
rapid and persistent hypoxemia following the introduction of
liquid at the entrance of the airway. 17,40,46,53,56,72 Arterial oxygen
decreases immediately, 17,39,56 and is accompanied by
acidosis and hypercarbia, although the arterial levels of carbon
dioxide (CO 2 ) are considerably below 17,56 the 95 mm of mercury
required for CO 2 -induced narcosis. 21,45,56 It is for these
reasons that drowning is not considered an acceptable method
of euthanasia by the American Veterinary Medical Association
41 and others 4,45 and is considered inhumane. 41 The survival
time is inversely proportional to the volume of fresh or
salt water aspirated in dogs, 53,56 although aspiration of as little
as 5 mL of salt or fresh water in dogs causes rapid and persistent
hypoxia without significant hypercarbia. 53,56
The drowning process (Fig. 2), reviewed extensively in the
medical literature 5,14,32,40,46,51,67,71,84 and largely based on
experiments in dogs, incorporates behavioral and biological
responses to drowning. 2,17,44,53,56,83 This has been categorized
into the 5 phases of drowning (Table 1). 52
Initially, there may be a few deep respirations, although
breath holding and vagal mediated laryngospasm usually occur
upon submersion 8,44 with an abrupt decrease in arterial oxygen.
As little as 2 mL of water contacting the larynx or aspirated into
the lung, can cause laryngospasm in dogs. 2 The laryngospasm
may last 1.5–2 minutes during which arterial CO 2 increases 72
and acidosis develops. 17,30,40 Bradycardia 2,54,81 occurs immediately
following submersion 8,26 or after brief tachycardia. 17,27
Blood pressure immediately increases and then progressively
decreases. 27,53
Submerged, nonanesthetized dogs struggle violently for 1.5
minutes, 44,52 and because the glottis is closed, thoracic inspiratory
movements are attempted and liquid is swallowed,
but 2,64,81 gas exchange does not occur. If unconsciousness
occurs due to hypoxemia, the larynx relaxes and water is aspirated,
47 or, if the animal remains conscious, apnea ceases and
water is aspirated and swallowed due to deep inspiratory gasping.
43 After 3 minutes, spasmodic convulsions and seizures
occur 27,44 and over distension of the stomach with water causes
violent vomition. 44 Electroencephalograph (EEG) activity varies
with the duration of initial apnea: the EEG became isoelectric
at about 3 minutes in dogs with brief initial apnea,
whereas dogs with initial apnea of 2 minutes had an erratic
EEG, that was isoelectric at 30 seconds, then reactivated at 2
to 3.5 minutes before becoming flat. 81 Cardiac asystole or
observed death occurs usually within 5 minutes, but occasionally
up to 10 minutes following submersion. 8,27,44,52,56,72,85 The
initial hypoxemia in fresh and salt water drowning is intensified
by pulmonary edema, and is exacerbated by exponential
catecholamine release, subsequent vasoconstriction, cardiac
arrhythmias, 17 pulmonary hypertension, and right to left intrapulmonary
shunting. 17,33,46
Electrolyte and intravascular changes during drowning
depend on the salinity and/or volume of water aspirated. The
biochemical effects of water are primarily osmotic 53,55,82,83
and not temperature related. 17 Distinguishing between salt
water and fresh water drowning is given little clinical significance
in people, 46,64 although some think that it does impact
successful resuscitation and chance for survival, 17 but it is
important to the forensic investigation. 16
Hemodilution, hypervolemia, decreased serum sodium,
chloride, osmolality, hematocrit, and hyperkalemia occur in
dogs drowned in fresh water. 17,55,72,82 The changes are temporary
due to redistribution of fluids within the body 53,72 although
the hemodilution and electrolyte alterations may persist if the
volume of water aspirated is 22mL/kg or above. 72,82 In dogs,
aspirated fresh water penetrates the circulation within 3 minutes,
47,53 andanestimated10% of the body weight can be
absorbed by the lungs during fresh water immersion. 17
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McEwen and Gerdin 3
Death due to salt water aspiration is more lethal than freshwater
aspiration, 8,9,36 requiring half (10mL/lb [4.5mL/kg]) the
aspirated volume as for fresh water (20mL/lb [9.1mL/kg]). 53,56
Drowning in hypertonic fluids of 2.5%-3.5% or seawater
results in hemoconcentration, increased serum sodium, osmolality
and potassium. 17,56 The aspirated hypertonic fluid pulls
fluid from the circulation into the alveoli, damaging the basement
membrane, with washout of surfactant and reduced lung
compliance. 24 Ensuing pulmonary edema decreases the ventilation/perfusion
ratio and right to left intrapulmonary shunts
develop. 46 Type I and II pneumocytes 10,88,89 and alveolar capillary
endothelium 10,36 are damaged by both fresh and salt water.
Neither hemolysis nor ventricular fibrillation are features of
experimental seawater drowning. 82,83
Drowning ultimately results in progressive cerebral
hypoxia 46 and death. Irreversible injury occurs in selective
regions of the brain within 4–10 minutes and persistent coma
develops within a few minutes after that time period. 23,62 The
precise outcome of hypoxic injury due to drowning is difficult
to predict even if the individual is rescued and resuscitated. 87
Figure 2. The drowning process.
Table 1. The 5 Phases of Drowning in Dogs. 51
Phase
Activity
1 Struggling
2 Violent intentional movement, escape attempts
Breath holding
3 Deep respiratory movements
Immobile
Swallowing
Convulsions
4 Loss of corneal reflexes
Dilated pupils
5 Few respiratory movements
Muscle fasciculations of head and jaw
Death
Dilutional hypovolemia was not present in a case series of dogs
and cats resuscitated following submersion in fresh water. 30
Hemolysis in dogs was not evident until over 5mL/lb
(2.3mL/kg) of water was aspirated. 54 Volume dependent ventricular
fibrillation is common, occurring in many but not all
dogs drowned by volumes of 20mL/lb (9.1mL/kg) but not by
10mL/lb(4.5mL/kg). 53 The ionic charges responsible for the
surface-tension properties of surfactant are altered by fresh
water which results in alveolar instability and pulmonary
atelectasis. 51,53 Atelectatic alveoli are perfused, but not ventilated,
and there is right to left intrapulmonary shunting, 51 further
exacerbating the hypoxemia.
Cold Water Immersion, Autonomic Conflict,
and Hypothermia
Humans suddenly submerged in water 5 C below body temperature
may become unconscious and develop cardiac
arrhythmia possibly due to vagal stimulation and/or catecholamine
release. 17,19,49,64,76 The parasympathetic and sympathetic
responses following rapid submersion and breath
holding are the diving response and cold shock response
respectively. 76 These responses are due to several reflex reactions
that produce a predictable sequence of physiological
events. 22 The diving response of apnea and bradycardia
found in all marine and land vertebrates studied, 76 is initiated
by activation of the cold receptors of the face via the ophthalmic
and maxillary divisions of the trigeminal nerve, although
vagal receptors in the pharynx and larynx produce similar
responses. 76 Cold thermoreceptors of the skin also mediate
the sympathetic associated cold shock response which causes
tachycardia, hyperventilation, peripheral vasoconstriction,
and hypertension. 19,76 Both responses can cause cardiac
arrhythmias independently, or together by issuing conflicting,
simultaneous signals to the heart. 22,37,76
Within 2 minutes of submersion in cold water, core body
temperature decreases more rapidly and deeply than with
immersion, 17 due to the aspiration of larger quantities of water
and contact with the large surface area of the pulmonary circulation.
Primary hypothermia due to submersion is fatal when
rectal temperatures drop to 20 C, or below. 63 The onset and
duration of cardiorespiratory and cerebral responses were similar
in dogs that had their tracheas clamped and submerged in
0–1 C water, 85 compared to those submerged in normothermic
or cold water but allowed to aspirate water. 2,44,82,83 The absolute
and relative decreases in rectal and cerebral temperatures
were proportional to the submersion time. Spontaneous circulation
could be restored in 75% of the dogs over the course of
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4 Veterinary Pathology
Figure 3. Drowning, dog. Lung. The lungs are distended and edematous with emphysema, petechiae, random atelectatic foci, and subpleural
hemorrhages. Figure 4. Drowning, dog. Trachea. Abundant stable froth and red-tinged fluid are present in the trachea. Figure 5. Drowning,
dog. Lung. Foreign material is present in an airway. Hematoxylin and eosin (HE). Figure 6. Drowning, dog. Lung. Same lung as in Figure 5,
adjacent to area with foreign body demonstrating only mild congestion and hemorrhage. HE.
1.5 hours using cardiopulmonary bypass, although spontaneous
breathing and return of EEG activity occurred in only 56% of
the dogs. 85 While these experiments concluded that resuscitation
of hypothermic submerged dogs is possible by extending
the time for reversible cerebral hypoxia, 17 the experimental
protocol removed the effects of aspirated liquid on the cardiopulmonary
system.
Morbidity
A case series of 25 dogs and 3 cats resuscitated following
submersion in fresh water concluded that the prognosis for
survival is good if respiratory tract failure and cardiac arrhythmias
do not develop. 30 Level of consciousness upon presentation,
even coma, was not associated with outcome. 30
Complications in animals that survive drowning include
reduced mentation or neurological deficits, 51 noncardiogenic
pulmonary edema, 29 septic pneumonia, 6 and acute respiratory
distress syndrome. 30
Macroscopic and Microscopic Lesions of
Drowning
Distended, heavy, edematous lungs that fail to collapse, and
stable froth in the trachea, mouth, or nasal passages are characteristic
of drowning (Fig. 3), but they are not specific, as
these may be due to other causes. 46,48 Emphysema aquosum
is a term used in medical forensic pathology to describe overinflated,
water-logged lungs with histologic findings of alveolar
dilation, thinning of alveolar septa and compression of
alveolar capillaries. 48,77 However, this term should be avoided
in veterinary pathology and it is better to specifically describe
the lesions for clarity. Tables 2 and 3 list macroscopic and
microscopic lesions in drowned animals. In individual cases,
these lesions may or may not be present. Stable froth in the
tracheobronchial tree (Fig. 4), larynx and, nostrils can be produced
only by a live animal 59 and may also arise with other
causes of pulmonary edema. 46 Blood-tinged froth is produced
by hemolysis of red blood cells within the fluid. 52 Amare
rescued from drowning had stable red froth at the nares and
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McEwen and Gerdin 5
Table 2. Macroscopic Lesions of Drowning Documented in Animals.
Lesion
Hair coat is wet, damp, 60 or hair if dried may be aggregated in spikes
Froth emanating from nostrils or oral cavity 26,43,48,60,79,80
Froth in larynx or airways 26,43,48,60,79,80
Lungs distended and fail to collapse 49,60
Pulmonary congestion and edema 2,26,34,43,60,70,84
Pulmonary hemorrhages 2,26,35,79,80
Pulmonary emphysema 26,43,60
Right ventricular distension 2,43
Water and or foreign material in stomach 2,43
Aspirated stomach contents or other foreign material in larynx or
airways 2,12,26,60
Mucus at the base of the tongue or in larynx 26
Fluid in the frontal or paranasal sinuses 49
Contusions or bruising in skin or subcutis if forcible submersion 49,60
Other traumatic lesions such as fractures 57
Table 3. Microscopic Lesions of Drowning Documented in
Animals. 60
Lesion
Intraalveolar hemorrhage
Flooding of alveoli with pale or proteinaceous fluid
Alveolar overdistension
Attenuation of alveolar septa
Aspirated stomach contents, bacteria or foreign material in alveoli or
airways
continued to expectorate this material by paroxysmal coughing.
1 Foreign material deep within the tracheobronchial tree
and lungs is compatible with aspiration rather than passive
entry following death (Fig. 5). 59 The presence, severity, and
type of pulmonary macroscopic and microscopic lesions are
not uniform, even within the same histological section (Fig. 6).
In humans, the external foam and stable froth may persist for
several days, even with the onset of putrefaction. 46 Both features
may disappear, or are altered by the effects of time, handling,
storage, and freezing of the body prior to postmortem
examination. Investigators should provide, or pathologists
should request photographs and documentation of the animal
at the recovery scene especially if the postmortem examination
is not immediate.
The amount of liquid penetrating the lungs depends on the
respiratory efforts, laryngospasm and time of cardiac arrest. 47
Previously, the majority of drownings in people were classified
as ‘‘wet-drowning’’ and the 10–15% without evidence of
aspiration as ‘‘dry-drowning.’’ A review of 1590 cases of
drowning in humans indicates that the estimate of ‘‘dry-drowning’’
is closer to 2%. 47 ‘‘Dry’’ lungs in human victims were
attributed to many causes such as sudden cardiac arrhythmias,
76 cardiac arrest or laryngospasm following submersion, 47
may represent one end of a spectrum of drowning lesions or,
more likely, deaths in water due to natural causes or are bodies
disposed in water. 47,52,64 The significance and pathophysiology
of ‘‘dry-drowning’’ is debated in medical forensic pathology, 47
and it is recommended that these terms should now be
avoided. 32 The pathophysiology of ‘‘dry-drowning’’ in humans
may not parallel that in animals: regardless of the volume of
water aspirated in dogs, even low volumes caused hypoxemia
and decreased lung compliance. 55,56 A lack of significant fluid
aspiration has been attributed to laryngospasm 44 or the failure
to gasp. 2 Lungs lacking evidence of aspiration are documented
in experimental drownings of muskrats and beavers that had a
mucus plug in the trachea. 26
Additional findings in humans that may support a diagnosis
of drowning are pleural effusion, subdural discoloration of the
petrous temporal bone due to congestion or hemorrhage in the
mastoid process and middle ear, hemorrhage in the neck muscles,
a contracted spleen, 46,71,77 Paltauf’s spots and hemolytic red
staining of the aortic intima, 13,15 and left heart. 92 Paltauf’s spots
are subpleural, intraalveolar hemorrhages, blurred due to hemolysis.
46 It is uncertain from the veterinary literature whether these
lesions have been accidentally overlooked as subpleural hemorrhages
are shown in Figures 3 and 5.
The appearance and approximate volume of gastric contents
should be documented as swallowing of water is common during
drowning, 2,44 and if vomited, may be aspirated. Gastric
mucosal lacerations due to over distension of the stomach with
water are sporadically reported in human drowning victims. 46
Elevated liver enzymes in animals resuscitated following submersion
were attributed to hepatic hypoxia and necrosis, but
this cannot be confirmed as histopathological examination of
liver was not described. 30 Hepatocellular necrosis 6 was confirmed
in 1 dog that aspirated water from a drainage ditch, but it
cannot be determined if this was due to the initial drowning or
sequelae such as cardiorespiratory failure. Myocardial lesions
of contraction bands and rupture of intercalated discs in the
cardiac myocytes of rats drowned in either salt or fresh water, 35
may be due to excessive catecholamine release.
A thorough postmortem examination will aid in determining
if significant intercurrent diseases are present, 30 and a medical
history of conditions such as epilepsy would also be useful
particularly in determining why an animal was unable to extricate
itself from the drowning medium. Hyponatremic encephalopathy
due to excessive intake of fresh water (water
intoxication) should also be considered, particularly in animals
that play or train in fresh water. 86
Weights such as blocks, tires or chains bound to the animal
indicate intentional submersion of the body, but if present,
should not be used to corroborate if the animal was alive or
dead at the time of submersion. Contusions, subcutaneous
hemorrhages, or other lesions of blunt force trauma of the head,
neck, or limbs may be present in animals that were forcibly
immersed or submerged in water. 50,59
Postmortem Changes
The postmortem submersion interval and postmortem changes
that occur while in water and following retrieval may make
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6 Veterinary Pathology
examination and determination of the cause of death even more
challenging. Early changes are skin maceration, lividity, rigor
mortis, and algor mortis, and late changes include initial putrefaction,
advanced putrefaction including adipocere formation,
and skeletonization. 25,46 Adipocere is a waxy material produced
on bodies submerged in water that results from degradation
of adipose tissue by endogenous and bacterial enzymes. 74
Postmortem changes in the water, as on land, are time- and
temperature-dependent. 46 The lower temperatures of bodies
of water usually retard rigor mortis and accelerate body cooling.
25,46 Decomposition while in water is slower than on land
however, once a body is removed from the water, the process
rapidly accelerates. The body initially sinks and then rises to
the surface once putrefactive gases increase buoyancy. 74 If the
water is cold enough, putrefaction may not occur and the body
may never resurface. Depending on the duration and conditions
of submersion, hair may slip from the skin and the entire body
may be waterlogged. 46 Scavenging by aquatic animals and
trauma inflicted by natural and man-made elements of the
aquatic environment, may create postmortem lesions or may
alter or destroy antemortem lesions. 46 Water may dilute antemortem
hemorrhages, and projectile, sharp force, or blunt force
injuries may be obscured or effaced by maceration. A small
study in 3 dogs identified enhancement of the supravital histological
changes of myofibre ‘‘disintegration’’ in muscle traumatized
up to 6.5 hours of death and submersed in seawater. 78
Ancillary Tests Used in Determination of
Drowning
Lung Weights
The increased weight of lungs and pleural fluid used to support
the diagnosis of drowning in humans is unreliable as many
variables influence the result. 32,38,47,64 Lung weights of
1000g 77 to 1400g 38 used to confirm drowning in humans is
misleading as there is no agreement in the medical literature
regarding normal lung weights. 47 Similarly, reference values
for postmortem lung weights are not available for most breeds
of animals and application of allometrically determined lung
weights 43,79 require further validation if applied in a forensic
context. A drowning index of the weight ratio of the lungs and
pleural effusion to the spleen has been proposed in humans to
be more accurate than absolute lung weights, 61 although it is
affected by postmortem interval and has a relatively low sensitivity
and specificity of 66% and 77.5% respectively. 80 It
remains to be determined if this measurement is accurate or
applicable to animals.
Diatoms
Perhaps no other ancillary test in the diagnosis of drowning in
humans has received as much attention, scrutiny, and debate as
the use of diatoms. 14,20,34,42,46,47,65,67–70,77,90 Diatoms are unicellular
algae with a silica cell wall (frustrule) that makes them
inert to acids, high temperatures and enzymatic digestion. 91
The use of diatoms as a diagnostic test for drowning is based
on the assumption that the individual must be alive for them to
be aspirated, penetrate the alveolar-capillary membrane, enter
the circulation, and enter tissues including marrow. 6,74 If meticulous
and usually time-consuming techniques are used to
retrieve diatoms, usually from the bone marrow, their presence
in large numbers may corroborate a diagnosis of drowning, and
their unique characteristics may identify the location and
drowning medium of the victim. The sensitivity of the method
is relatively low and depends on the time of year when the
algae bloom. 70 The specificity may be high with the appropriate
techniques; however, the prospect of contamination during
the postmortem submersion interval and sample preparation is
high, resulting in false positive results. 25 As diatoms have been
found in bodies not recovered from water and in living people,
the possibility that they enter the circulation from ingested food
must be considered. 91 Although diatoms were identified in the
tracheal wash of a dog that aspirated during a seizure in a
water-filled drainage ditch, 6 application of the diatom test to
confirm drowning in animals requires additional rigorous validation
studies.
Electrolyte Tests
Differentiation between salt water and fresh water drownings
using electrolyte levels in blood or vitreous humor does not
appear to have been widely accepted. The Gettler test comparing
chloride levels in right and left ventricular blood, 77 is determined
to be unreliable. Elevated vitreous humor sodium levels
in cases of salt water drowning and decreased levels in fresh
water drowning, proposed as a marker of the drowning
medium, 16 may be useful but require further validation.
Conclusion
Diagnosis of drowning is difficult 12,46,48,50,59 as bodies recovered
from water may or may not have drowned. A thorough
postmortem examination is necessary to identify and document
the presence and absence of lesions that may corroborate or
rule out death due to drowning, to identify intercurrent disease
that may have influenced the animal’s behavior in or around the
water and to identify traumatic injuries consistent with nonaccidental
injuries of forced submersion or immersion. While
there are characteristic macroscopic and microscopic lesions
of drowning, none are specific. Additional information from
the crime scene investigators, including witness accounts, an
accurate history, previous medical conditions of the animal,
and disposition of the body when retrieved from the drowning
medium are often needed to allow the pathologist to consider
the postmortem findings in context.
Acknowledgements
We thank Dr Sean McDonough and Dr Murray Hazlett for their photographic
contributions.
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McEwen and Gerdin 7
Declaration of Conflicting Interests
The author(s) declared no potential conflicts of interest with respect to
the research, authorship, and/or publication of this article.
Funding
The author(s) received no financial support for the research, authorship,
and/or publication of this article.
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