Infectious/Non-Infectious
Agent associated with the Disease
|
- Exposure to wind. (B123.6.w6)
- Direct contact with a cold surface. (B123.6.w6)
- Restriction of exercise. (B123.6.w6)
- Cold ambient temperatures. (B345.4.w4)
- Anaesthetic/chemical restraint drugs can impair central
thermoregulatory mechanisms, decrease metabolism and/or decrease
endogenous heat production (e.g. prevent shivering). (B123.6.w6,
B345.4.w4)
- Loss of insulation - soaked coat, oiled fur or feathers, or
malnourishment leading to a reduced subcutaneous fat layer. (B345.4.w4)
- Inadequate circulation due to shock. (B345.4.w4)
In birds:
- Usually a combination of low environmental temperature and wet
down/plumage.
- Waterproofing and insulation depends on structure and arrangement of down
and feathers. Disarrangement of feathers, general soiling , or contamination with any
substance which interferes with these functions (e.g. oil, detergent, soap) increases
susceptibility to chilling.
(J2.12.w2, J7.30.w2,
J40.31.w2, J58.106.w1)
In mammals:
- Usually associated with low environmental temperatures, particularly
in individuals which are small, in altricial
young, and in association with wet/contaminated fur.
- In altricial young, hypothermia will occur even in temperate
conditions in the absence of the mother or an alternative heat source.
(V.w5, B20.13.w10,
B20.14.w11, B123.6.w6,
B151) |
Infective
"Taxa" |
-- |
Non-infective agents |
|
Physical agents |
|
|
|
Disease Author |
Debra Bourne |
 |
Major References /
Reviews
|
Code and Title List |
B9.6.w1, B11.40.w8, B13.46.w1, B15, B18, B20.14.w11, B37.x.w1, B41, B123.6.w6,
B345.4.w4
P3.1987.w1
P4.1990.w1
P14.5.w7
J2.12.w2
J7.30.w2
J40.31.w2
J58.106.w1
V.w5
Hedgehogs:
J180.26.w1, B284.6.w6,
B337.2.w2, B337.3.w3
Bears:
D249.w13,
D247.6.w6,
J417.20.w1
Lagomorphs:
B338.1.w1, B600.3.w3,
B600.5.w5,
B601.3.w3, B602.13.w13,
B603.1.w1, B616.7.w7,
B618.21.w21, J15.30.w2,
J34.17.w1, J213.1.w1,
J417.18.w1, P113.2005.w4
Ferrets:
B338.26.w26, B627.8.w8, B631.18.w18
J195.11.w2, J513.7.w3
|
Other References
|
Code and Title List |
-- |
Detailed Clinical and Pathological Characteristics
|
General |
- Feel cold to the touch, particularly on the extremities.
- Body temperature is lower than normal for the species.
- Below 35 °C/95 °F. (B345.4.w4)
- Commonly will shiver. (B123.6.w6,
B345.4.w4)
- May show decreased movement.
- May appear depressed, with slower than usual reactions and responses
to stimuli. (B123.6.w6)
- Young animals may huddle together.
- Juveniles may not suckle.
- Heart rate decreased, blood pressure decreased (pulse is difficult
to feel). (B345.4.w4)
- Below 32 °C (89.6 °F), the animal may be comatose and unable to
respond to stimuli. (B123.6.w6)
- Below 30 °C (86 °F), breathing becomes slow and shallow.
- Additionally there may be "sludging" in the
microcirculation, metabolic acidosis, ventricular fibrillation and
disorders of coagulation. (B123.6.w6)
(B20.14.w11, B123.6.w6,
B345.4.w4, V.w5) |
Clinical
Characteristics
|
BIRDS |
- When ambient temperature falls below the lower critical temperature
(the ambient temperature below which the bird cannot thermoregulate
solely by physical/behavioural means), the bird increases heat
production by breakdown of ATP (which is restored by increased
oxidation of fats, carbohydrates and proteins), together with
peripheral vasoconstriction, piloerection and shivering. Increased
oxygen use causes increased respiratory rate, heart rate, blood
pressure and cardiac output. (P14.5.w7)
- Reduced body temperature (can be below 100 °F (37.7 °C) (Normal
body temperature for avian species averaged 104-106 °F, 40-41 °C).
(P14.5.w7)
- With mild hypothermia the affected individual is cold to the touch,
depressed, and may be shivering. (B20.14.w11)
- Mental depression, impaired coordination and lethargy; (P14.5.w7)
- Progression to muscle rigidity; (P14.5.w7)
- Finally decreased pupillary reflexes, sinus bradycardia, depressed
respiratory rate, increased blood viscosity, therefore reduced cardiac
output, hypotension; (P14.5.w7)
- The affected individual may enter a coma and appear dead; (P14.5.w7)
- Dysrhythmias, pre-ventricular contractions, ventricular tachycardia and cardiogenic shock may occur. (P14.5.w7)
- Metabolic acidosis may occur due to lactic acid accumulation from
shivering combined with decreased liver metabolism; respiratory
acidosis may occur due to reduced respiratory rate and sludging of
blood. (P14.5.w7)
- Renal diuresis may occur due to reduced tubular reabsorption
(resulting from vasoconstriction increasing blood volume). Later as
cardiac output decreases, renal blood flow and glomerular filtration
rate decrease. (P14.5.w7)
- Hypoglycaemia may occur as energy reserves become exhausted. (B20.14.w11)
- Additional effects include: reversible platelet dysfunction, ascites,
predisposition to stress-associated diseases, possibly increased
susceptibility to airborne pathogens since bronchial secretions become
thick and tenacious, possible increased susceptibility to infections
associated with impaired phagocytosis and granulocytopaenia.
Coagulopathies, pulmonary oedema, pneumonia and cerebral oedema are
possible complications may occur also. (P14.5.w7)
WATERFOWL
Downies/juveniles:
- Huddling of brood, wet, bedraggled look; shivering may or may not be
seen.
- Severe chilling ducklings may be limp, limbs may be hyperextended, and
the ducklings may appear dead.
- Reduced body temperature.
- May recover initially then develop gastro-intestinal or septicaemic
disease a few days later.
- Remarkable recoveries may be seen, particularly in very young waterfowl (B41,
V.w5).
(J58.106.w1,
B11.40.w8,
B13.46.w1, B37.x.w1,
P4.1990.w1).
Adults:
- Depression, lethargy, shivering, feel cold when touched.
- Reduced body temperature: below 90°F with severe hypothermia.
(J2.12.w2, B11.35.w3,
B20.14.w11, P4.1990.w1, P14.5.w7). |
| HEDGEHOGS |
- Wobbling, or standing and rocking. (B337.2.w2,
B337.3.w3)
- Feel cold to the touch (e.g. on the belly), with cold mucous
membranes (e.g. gums). (B284.6.w6,
B337.3.w3)
- May appear only semi-conscious. (B337.3.w3)
Hoglets:
- May remain immobile and partially curled up for much
of the time, with occasional stretching, crawling and sniffing with
the eyes closed.
- Cold to the touch.
- Generally unwilling to take food.
- May be apparently unconscious.
- Body temperature may be as low as 17.5°- 20°C when
examined initially compared to a normal temperature for hoglets of about
31.5-34.0°C (See: West European hedgehog - Detailed Physiology (Literature Reports)
- Temperature).
(J180.26.w1)
|
| BEARS |
- Lethargy. (J195.11.w2)
- Cubs may be cold to the touch and if very cold, feel rigid. (J23.11.w3,
J23.11.w4)
- Reduced rectal temperature; normal is 37.5 - 38.3 °C (99.6 - 101.0
°F).
(B16.9.w9)
- If the body temperature falls below 96 °F and is still falling,
warming is required. (D249.w10)
|
| LAGOMORPHS |
- In domestic rabbits, a temperature at or below 38.0 C (100.4
°F) is subnormal; normal is 38.5 - 40 °C (101.3 - 104 °F). (B600.3.w3)
- Normal temperature is about 37.8 - 39.4 °C (100 - 103 °F) for
most rabbits and hares; temperatures below this indicate chilling.
(B338.1.w1)
|
| FERRETS |
- Body temperature below 36.6 °C (98 °F); normal range is 37.7 -
38.8 °C, 100-102 °F. (J513.7.w3)
- Moderate/severe hypothermia, core body temperature below 35
°C (95 °F). (J513.7.w3)
- Hypothermic kits will be still, not active, and will feel cold
when touched. (B232.11.w11)
- Hypothermic kits will not suckle. (B338.26.w26,
B627.8.w8)
|
Incubation |
WATERFOWL |
-- |
Mortality / Morbidity |
WATERFOWL |
-- |
| HEDGEHOGS |
- Mortality may be due to hypothermia and starvation,
or predation, or blowfly strike (Myiasis).
(J180.26.w1)
|
| LAGOMORPHS |
--
|
| FERRETS |
--
|
Pathology |
Pathological
changes may be mild and non-specific:
- Lungs - often congested.
- Liver - often pale.
- Stomach - Usually empty.
- Body cavities - may contain excess clear fluid
(B20.14.w11) |
| WATERFOWL |
- Mild, non-specific changes:
- Lungs - may be congested.
- Liver - may be pale.
- Gizzard - Usually empty.
- Body cavity - may contain excess clear fluid
- May be fluid in respiratory tract due to death by drowning
(Drowning).
(J2.12.w2,
B20.14.w11). |
| HEDGEHOGS |
-- |
| LAGOMORPHS |
-- |
| FERRETS |
-- |
General Information on Investigation / Diagnosis
|
- Clinical signs including shivering, huddling, wobbling gait.
- May feel cold to the touch, with cold mucous membranes.
- Body (rectal) temperature below normal for the species and age.
(B20.14.w11, V.w5) |
| WATERFOWL |
- Clinical signs: huddling of broods, sometimes shivering, lying still and
limp, appearing dead with severe chilling. Depression / lethargy and shivering in adults.
- Reduced body temperature: below 90 °F with severe hypothermia (P4.1990.w1).
|
| HEDGEHOGS |
- Clinical signs: cold hoglets, reduced movement, may
be unwilling to suckle. (J180.26.w1);
in adults and hoglets wobbling or standing and rocking. (B337.3.w3)
Will feel cold to the touch. Low rectal temperature (normal about 35
°C). (B284.6.w6)
|
| LAGOMORPHS |
--
|
| FERRETS |
- Clinical signs: in kits, lack of movement, and feeling cold when
touched. (B232.11.w11,
J195.11.w2)
Also failure to suckle. (B338.26.w26)
- Body temperature below 36.6 °C (98 °F); normal range is 37.7 -
38.8 °C, 100-102 °F. (J513.7.w3)
- Severe hypothermia, core body temperature below 35 °C (95 °F).
(J513.7.w3)
|
| Related Techniques |
|
 |
General
Nursing and Surgical Techniques
|
|
Treatment needs to restore normothermia, prevent further loss of heat,
support the vital organs, restore fluid volume, maintain the animal's
airway and also address any secondary problems. (P14.5.w7)
Note: The body core must be warmed before the extremities are
warmed. (P14.5.w7)
- Restoration of body temperature: Warm gradually to about 24-30 °C (mammals) or 32-38 °C (birds). (B20.14.w11)
- Small animals can be rubbed dry (if they are wet) and body heat
used (place the animal inside your clothes, next to your skin
until more effective warming methods are available). (B123.6.w6,
B345.4.w4,
V.w5)
- Warm using containers of warm water placed against the animal,
blankets, hand warmers, electric heat pads or heat lamps, as
available. (B345.4.w4,
V.w5)
- Mild hypothermia: Passive rewarming with blankets, hot
water bottles, brooder lamps or heat lamps may be sufficient. (P14.5.w7)
- Moderate hypothermia: warm with heat sources such as hot
water bottles or heat pads, placed adjacent to the ventrolateral
thorax and NOT in direct contact with the skin. Radiant
heaters such as heat lamps should be placed at a safe distance
(depends on the wattage). (P14.5.w7)
- Severe hypothermia:
- Immersion in a warm water bath (40.5 - 45.5 °C, i.e.
105-114 °F) is the most effective way of warming the animal.
Keep the head out of water and ruffle the fur or feathers to
make sure the warmth is reaching the skin. (B123.6.w6,
P14.5.w7)
- For large animals where full immersion is not possible,
spray with warm water or wrap in warm blankets and massage
the body surface. (B123.6.w6)
- Once the animal is warm, dry with warm air using a
hand-held hair drier. (B123.6.w6)
- Note: For conscious wild animals, use
of a drying pen, away from human contact, is less
stressful than drying with a hand-held drier. See: Cleaning Oiled Wildlife
- Drying Birds.
- Do not wet the animal with warm water unless a
means of drying it thoroughly is also available. (B345.4.w4)
-
Warming in a stream of warm air or warm water may be possible. (P14.5.w7)
- Warm water enemas can be used. (B123.6.w6)
- Maintain in an ambient temperature of about 19 to 21 °C after
rewarming. (B11.35.w3)
- For wild animals which have been immobilised, do not allow
recovery and release until the animal's body temperature is back
to above 38 °C/100 °F. (B345.4.w4)
- Fluids therapy:
- Give warm intravenous fluids (normal saline). (B123.6.w6)
- In severely hypothermic individuals it may be necessary to
expose a vein surgically (cut-down) as the decreased blood
pressure associated with hypothermia may make it difficult to
locate the veins. (B123.6.w6)
- Give birds warm fluids by intravenous or intraosseous injection,
up to 3% of body weight at one time by bolus injection, repeated
every three to four hours if required. (P14.5.w7)
- If the bird is conscious and maintaining head carriage oral
rehydration can be given; fluids should be supplemented with
dextrose and/or a readily digested food. (P14.5.w7)
- If conscious, provide dextrose in water, and easily digestible food
(offer little and often). (B20.14.w11)
- Monitor respiration and maintain an airway:
- Intubation and ventilation with warm oxygen has been suggested
if hypoventilation (les than four to ten breaths per minute)
develops. (P14.5.w7)
|
| WATERFOWL |
- If mildly chilled, the bird will warm up if given access to a heat source e.g. an
infra-red lamp.
- Birds which have become more severely wet and chilled may be warmed and
dried, for example by careful use of a hair dryer, or by placing in a
stream of warm air from a fan heater.
- Individuals my also be warmed by washing gently in clean water at 37.5°C
(100°F).
- Hot water bottles may be used with care - alongside the ventrolateral thorax,
not in direct contact with skin (e.g. wrap a hot water bottle in a towel first).
- Downies may be rubbed dry and held against a person's body (direct skin
contact) initially while other arrangements for warming are being made.
(V.w5)
- Monitor temperature e.g. with cloacal thermometer.
- Once warm, tube feed with a prepared formula such as Emeraid I, (Lafeber,
Odell, Illinois, USA) - e.g. 0.25-0.3 mL per duckling, depending on size.
- Maintain in an ambient temperature of about 19 to 21 °C after
rewarming. (B11.35.w3)
(J2.12.w2,
J58.106.w1, B11.35.w3,
B13.46.w1, B37.x.w1,
B123, P14.5.w7,
V.w5) |
| HEDGEHOGS |
- Provide warmth using a heat lamp, heat pad, hot water bottle, heated
cage etc. (B284.6.w6,
B337.3.w3)
- Warm gradually: avoid overheating the casualty or heating it too quickly. (B337.3.w3)
- If the individual is mobile, provide a heat gradient so that it
can choose the most comfortable temperature. (B337.3.w3)
|
| BEARS |
Adult bears
- Increase the ambient temperature (in the field, this can be achieved
by lighting a fire. (D249.w13)
- Place non-toxic chemical heating pads into the bear's axillae. (D249.w13)
Cubs
- Warm in a hot water bath if necessary. (J23.13.w15)
- Place in a warm incubator. (B338.24.w24,
J23.13.w15)
at 30-32 °C (86-88 °F)
- Surround the cub with clean latex gloves filled with warm water, or
warmed 250 ml saline bags. Replace with fresh warm fluid-filled bags
as they become cool. (B338.24.w24)
|
| LAGOMORPHS |
- Provide supplemental heat to individuals recovering from surgery,
collapsed individuals, and lethargic individuals, until they are able
to resume normal thermoregulation. (B600.5.w5,
B601.3.w3, J15.30.w2)
- Take care not to overheat the animal, remembering that rabbits
are susceptible to hyperthermia (Hyperthermia - Sunstroke - Heatstroke). (B600.5.w5,
J15.30.w2)
- Warmed intravenous fluids can be used. (J15.23.w6)
- Temperature-controlled incubators can be used. (J15.23.w6)
- Heat lamps can be used, with care. (J15.23.w6)
Rabbit kits:
- Kits which have become chilled (e.g. outside the nest) should be
placed in a box in a warm place. (B616.7.w7)
- If the neonate has a body temperature reduced by 3 - 4 °C (5 -
6 °F), re-warm by immersing in warm water (37.8 C/100 F) keeping
its head out of the water and massage it gently, for up to
five minutes. Then take it out of the water and keep it warming
under a heat lamp of drier. (B338.1.w1,
J417.18.w1)
- Warming may make any dehydration of the neonate worse.
After initial warming, give fluids. (B602.13.w13,
B338.1.w1)
- Fluids should be isothermic, i.e. warmed to 37.8 °C (100 °F).
(B602.13.w13)
- Lactated Ringer's solution is appropriate. (B602.13.w13,
B338.1.w1)
|
| FERRETS |
- Active rewarming is important in ferrets with moderate or severe
hypothermia i.e. core body temperature below 35 °C (95 °F). (J513.7.w3)
This can be accomplished using:
Ferret kits
- Give a few drops of glucose solution orally (B232.11.w11,
B338.26.w26, B652.7.w7,
J195.11.w2)
once it has revived sufficiently to take the fluid. (B652.7.w7)
- 1 mL of 10% glucose solution. (J195.11.w2)
- Warm the kits (J195.11.w2)
using human body heat (B232.11.w11,
B652.7.w7) or a heating pad; avoid warming too
quickly. (B232.11.w11)
- Kits can also be held in warm water to warm them. (B338.26.w26)
- A well-padded hot water bottle can be used. (B652.7.w7)
- Warm fluids can be given subcutaneously. (B232.11.w11)
-
0.5 - 1.0 mL warm fluids subcutaneously. (B338.26.w26)
- After warming, foster or replace with the jill, as appropriate.
(B232.11.w11)
|
| Related Techniques |
|
 |
Environmental
and Population Control Measures
|
| General Environment Changes, Cleaning and
Disinfection |
-
Ensure adequate heating is provided in
accommodation, particularly for debilitated individuals. (V.w5,
B284.2.w2)
-
For mobile casualties provide a temperature
gradient so that the individual can choose the place at which it
feel most comfortable. (V.w5)
-
The thermoneutral range (in which no additional
energy must be expended purely in order to maintain body
temperature) is 15-24 °C for most mammals, 15-25 °C for birds of
about 500 g to 1 kg, 20-30 °C for small birds of about 50-500g
and 25-35 °C for very small birds of 5-50 g. (B284.2.w2)
-
In the field, place an insulating pad between
an immobilised animal and the cold ground, and cover it or wrap it
in a rug or space blanket. (V.w5)
-
Use a suitable heat pad during general
anaesthesia for small species/individuals, minimise removal of
fur/feathers and wetting of the skin, particularly with alcohol,
and if possible wrap the patient in foil or bubble wrap to reduce
heat loss. (B205.17.w17)
-
Heating pads with circulating water are
preferable to avoid hypothermia and are less likely to become too
hot than are electric pads or blankets. (B123.6.w6)
|
| WATERFOWL |
- Ensure proper heating and brooding of young birds. Use
wire lids on brooder boxes to prevent downies jumping out and becoming chilled. Provide a
temperature gradient in brooder boxes, with a temperature under the heat lamp of
37.2 ºC (99 ºF) initially, which may be reduced gradually to 21.1ºC
(70 ºC) by about three weeks
old. Check brooder box temperatures and increase heating if required on cold nights. Avoid
drafts.
- Downies are less likely to become soaked and then chilled if reared with
restricted access to water e.g. providing only a shallow dish with pebbles in), but this
is not suitable for species such as the fish-eating ducks and the stifftails Oxyura
spp..
(See: Rearing
of Birds).
- Avoid cross-fostering between species with different habits, e.g. cygnets of
Cygnus cygnus
- Whooper swan onto adults of Cygnus olor
- Mute swan, as the whooper cygnets will
move to land to be brooded, while the foster parent (a species which frequently broods its
cygnets on its back on the water) may stay on the water.
- Ensure adults have access to shelter in winter, and ample food.
- Ensure oiled birds are kept in warm conditions until they have been washed and regained
their normal insulation (See: Oiling).
(P3.1987.w1,
B13.46.w1, B18,
B37.x.w1,
V.w5). |
| HEDGEHOGS |
- Ensure adequate heating is provided in accommodation. (B337.2.w2,
B337.3.w3)
- For mobile casualties provide a temperature gradient so that the
individual can choose the place at which it feel most comfortable.
(B337.3.w3)
|
| BEARS |
- If bears are chemically immobilised outside in low ambient
temperatures, wrap the bear in a space blanket or place it on an
insulating pad. (D249.w13)
- During surgery in cold conditions, place hot water bottles along the
sides of the bear. (V.w89,
V.w90)
- During hand-rearing, keep young cubs, which are not yet properly
haired and able to thermoregulate, in a warm, constant
temperature-controlled environment, such as an incubator. (B338.24.w24,
J23.13.w15)
- Take care to keep young cubs warm even when they are out of the
incubator during feeding and toileting. (B338.24.w24)
|
| LAGOMORPHS |
- For disinfection of the surgical field, preferably use warmed,
non-volatile disinfectant fluids; avoid use of large quantities of
spirit. (B600.15.w15,
B618.24.w24)
- During surgery, ensure the rabbit is on an insulating or heated
surface. (B618.24.w24)
- Warm any intravenous fluids given. (J15.30.w2,
J213.1.w1, P113.2005.w4)
- If the abdominal or thoracic contents are exposed for any length of
time, steps must be taken to prevent development of hypothermia and
dehydration. (J34.17.w1)
- Heat may be provided by circulating hot water blankets, hot
water bottles or heat lamps. (J34.17.w1)
- During abdominal surgery, periodic irrigation of the abdominal
cavity with warm sterile isotonic solution may be helpful. (J34.17.w1)
- Provide supplemental heat to individuals recovering from surgery,
collapsed individuals, and lethargic individuals, until they are able
to resume normal thermoregulation. (B600.5.w5,
B601.3.w3, J15.30.w2)
- Hand-reared rabbit kits should be kept warm and dry. Provide bedding material into which they can burrow, such as
hay and rabbit fur, a towel
or shredded tissue paper, and keep them in a warm environment. (B284.10.w10,
B338.1.w1, B606.6.w6)
See: Rearing of Mammals
- Hand-rearing
|
| FERRETS |
- If a collapsed ferret is to be transported (e.g. to a veterinary
clinic) it should be wrapped in a towel and placed on a hot water
bottle or hand warmer during the journey. (B631.18.w18)
- Peri-surgical care:
- The area of fur clipped for surgery should be
minimised, alcohol rinses avoided during aseptic preparation, and
external heat sources should be available. (B631.23.w23)
- Core body temperature should be monitored during surgery. (B629.13.w13,
B631.23.w23)
- During surgery, a heat source should be used under the ferret and if
necessary also an overhead heat lamp. (J29.6.w3)
- Intravenous fluids and and fluids used for flushing (e.g. in the
abdomen) should be warmed prior to use. (J29.6.w3)
- Kits:
|
| Population Control Measures |
-- |
| Isolation, Quarantine and Screening |
-- |
| Related Techniques |
|
 |