is one of the main building blocks of all living organisms. Without fluids,
our cells cannot function. Without our cells to manufacturer energy and
the many chemicals a body needs to function, and to spread those chemicals
and nutrients absorbed from food throughout the body, the body dies.
With insufficient fluids
in the body, the bodys function is compromised. It cannot sustain
all functions necessary for life, and so it starts shutting down operations,
closing more and more as the condition worsens, either through the rapid
loss of fluid or the failure to obtain sufficient fluids.
The mere act of being
alive requires a certain amount of energy (calories) and fluid intake
on a daily basis (or aggregate basis, in the case of those species that,
as a normal course in healthy members of the species, eat less often than
once a day). If, in addition to just sustaining the minimum body functions,
the body must also grow, engage in reproduction, experience stress, recover
from injury, etc., additional calories and fluids are needed to support
the extra demands over and above the basal metabolic requirements (BMR),
the bare minimum needed to sustain life.
With reptiles, the
fluid requirement issue becomes a bit more complicated as reptile species
are found in such a wide range of habitats and live a variety of life-styles.
Each species has adapted to its environment over millions of years. If
their environment changed very slowly over long periods of time, some
members of the population adapted to the changes and survived; those who
didnt died. Eventually, the populations were composed of those individuals
whose ancestors best adapted to the changes.
Adapting to life in
captivity cannot be compared to the thousands or millions of generations
required for a wild organism to adapt to a changing environment. Captivity,
even under the best of circumstances, rarely duplicates everything the
organism would be subjected to in the wild, including the variables found
in water constituents, nutritional and other variables in food animals
or plants, amount ultraviolet radiation, microclimates, etc. Many species
may appear to adapt quite well and go along for years, portraying the
very picture of health and well-being, only to be felled at a relatively
early age to organ failure due to something related to the captive environment,
or fails to rally after an apparent minor stressor.
Stress itself is a
factor in behavior, health, illness, and recovery. Since captive animals,
even apparently well-adjusted ones, are living in a condition of chronic
stress, routine captive care practices must include mediations to help
overcome or compensate for the long term effects of stress.
What this all means
is that it is important that you provide fluids (including humidity) on
a daily basis according to your species needs, and that when your
reptile is under particular stress you make sure that any extra fluids
necessary are administered.
kinds of stressors can lead to dehydration?
- Being housed in
a room cooled by air conditioning.
- Being housed in
a room heated by central heating or space heaters.
- Being housed in
an enclosure heated to attain and maintain the species required thermal
gradients and basking temperatures.
- Temperatures higher
than optimum thermal gradient recommended for species.
- Providing water
only once a week or only on feeding days.
- Providing water
in such as way as to be inaccessible (wrong type of container; standing
rather than moving; standing rather than drip or spray, etc.).
- Thermal or chemical
- Diet consisting
primarily of dried or pelleted commercial food products or desiccated
- Being in captivity
(see Signs of Illness and Stress
for other symptoms).
Providing the basic
daily fluids may be as simple as installing a bowl or pan of water that
your reptile can easily drink from or soak in. For large reptiles, this
requires both a suitably large enclosure in which to house the large reptile
and its large tub of water and still leave plenty of room for him to move
around, thermoregulate, etc. Drip systems, which may be a primitive as
a homemade drip bottle or an expensive green house mister, will be needed
for species native to humid climates. For other species, an area of substrate
will need to be kept damp, or a humidity retreat box provided some or
all of the time. These suggestions and more can be found in my article
Note On Heating vs. Dehydration...
wrote to me stating that they were keeping their reptile's room and enclosure
cool so as not to dehydrate them. While this person's desire to prevent
dehydration is good, the way they were going about it - by depriving the
reptile of the temperatures it needed for its body to function properly,
was just as ultimately deadly as heating it properly without regard to
hydration. Reptiles are complicated animals, with species-specific thermal
requirements that must be met for the animal to not only subsist, but
thrive. You cannot sacrifice one environmental for the other, but must
provide them to ensure overall health and functioning.
Green iguanas -
a particularly problematic species
(Iguana iguana) are complex lizards whose captive requirements drive many
iguana keepers running, babbling, and blithering for their own basking
spot. One of the problems with keeping green iguanas in captivity is keeping
their environment humid enough for them without destroying their captive
environment rotting wood and moldy drywall are hardly conducive
to keeping an iguana healthy. Enclosures made of suitable mesh products
are great for providing adequate ventilation, but they are almost impossible
to keep heated properly without heating the entire room. Thus, green iguanas
tend to be rather high maintenance lizards as keepers struggle to provide
the humidity needed to fend off early kidney failure while keeping them
warm enough to enable proper systemic functioning. Sufficient fluids are
particularly critical when the iguana has suffered a thermal burn, is
gravid, or is on systemic antibiotics for an infection or fighting a mild
infection without antibiotics.
Ways to increase iguana
and other wet, rain, and cloud forest species' humidity and fluid intake
- For tolerant species,
daily baths in water 80-85 F (26-29 C). Not only do long soaks let them
breath in humidified air and help them during their frequent sheds,
but some water is absorbed through the tissues inside the cloaca, and
many iguanas will drink more deeply when their bodies are in water.
An added bonus is that many iguanas prefer to poop in the bathtub rather
in their enclosure.
- Spraying them several
times a day with tap water increases the immediate ambient humidity
and is also good for skin getting ready to shed. Using a power-spray
bottle (one with a pump mechanism on top to pressurize the bottle, and
a simple locking push button to release the spray) makes this easy to
do, especially for people with repetitive motion stress conditions.
- Running a good humidifier
(cool air mist) 12+ hours a day can increase ambient room humidity.
Get one with a reservoir of 2-4 gallons so that you are not have to
refill it more than once a day. Vaporizers produce hot steam and, while
it is unlikely that the iguana may burn itself on the steam, the unit
can get hot and may cause a burn if the iguana lays on it.
- Keeping a pan or
tub of water with a large surface area in the enclosure will only marginally
increase the ambient humidity, but it does give the iguana a place to
soak or stand in a drink...and poop, so be sure to check it frequently
so it can be cleaned and disinfected as needed.
- Wet the leafy greens
with tap water before serving.
- Offer juicy fruits
or wetted leafy greens or edible flowers as treats.
- Install a fogger
or misting system made for agricultural or herptile hobbyists.
speaking, the daily fluid intake for reptiles is
Lizards and snakes
1-2% total body
2-3% total body
Another way to determine
fluid requirements is to give 20-25 ml/kg every 1-2 days.4,
solutions used for rehydration (and provided by your veterinarian) have
specific quantities, determined anecdotally
diluted with ringer's to no more than a 5% concentration
of total body weight5
q 24-48 hr*
LRS + 2.5% dex
2.5% dex + 0.45% Saline + 1 part LRS
q 24-48 hr*
Comments: In Chelonians
(turtles and tortoises) total fluids given at one time should not
exceed 2-3% of total body weight.6
Mild hypotonic solutions
are used first to provide intracellular diffusion of water. The solute
of choice is:
1 part D5W + 1 part
Normosol, up to 4% BW q 12-24 h
Fluids can be administered
subcutaneously, intracoelomically, intravenously, or intraosseously. Do
not administer intracoeloemically if there is a suspected space-occupying
lesion, pneumonia, obstipation, egg retention, or preovulatory follicles.
The daily amount of fluid cannot be administered all at once; instead,
it should be divided into 4-5 doses. This prevents overloading the kidneys.
Under normal circumstances, healthy animals who are eating and drinking
normally and who are living in an environment that meets their humidity
needs will succeed in keeping hydrated. The factors
described above can lead to dehydration, especially in wounded or starved
animals. Green iguanas and others species who evolved in high-humidity
environments may experience a chronic low level of dehydration throughout
their captive lives that ultimately cause kidney damage and an early death
due to kidney failure.
This strain on the
kidneys can be worsened if the iguana is put on systemic antibiotics,
so all antibiotic therapy should be accompanied by fluid therapy to ensure
the iguana is getting sufficient fluids for his normal daily needs as
well as additional fluid to compensate for the effect of the drug on his
kidneys. If your vet prescribes oral or injectible antibiotics for your
iguana, be sure to ask about supplemental fluids (PO, IC or SQ) during
the time the iguana is taking the antibiotics.
Routes of Administration
various ways that fluids can given to a sick reptile or one requiring
additional fluids for a specific reason, such as in conjunction with systemic
antibiotic therapy, or to correct moderate to severe dehydration. Reptiles
who have been starved to the point of emaciation will require rehydration
before nutritional support can be started. The following routes of administration
are for these exceptional needs, not for administering basic maintenance
fluids on a daily basis to an otherwise healthy reptile.
In mammals, fluids
are generally given by IV as it is the most
direct and efficient way to get the fluids into and circulated throughout
the body. Unfortunately, this is tricky at best when it comes to reptiles,
as anyone who has ever tried to draw blood from a major blood vein in
a reptile knows. Since fluids are most often administered at home by the
reptile keeper, most of whom do not have experience hitting a vein intentionally
(and repeatedly) in their reptiles, there are other ways that are easier,
though it may cause the reptile keeper more stress than it does their
PO (per os)
or anything else by mouth to reptiles can be difficult, given the vast
numbers of sharp teeth, the glottis, and often
cranky disposition a sick reptile may have. When dealing with venomous
reptiles, matters are rather compounded by the fact that you may get more
than a few teeth left behind in a bite wound.
When giving fluids
by mouth, you need to watch out for the glottis that sits on the tongue
at the back of the mouth in most reptiles; in chameleons and snakes, the
glottis will be behind the tongue sheath. When using a French catheter
or feeding/dosing tube attached to a syringe, you need to insert it into
the mouth, sliding it down one side of the mouth or the other to avoid
accidentally threading it into the glottis. While the ideal is to insert
the tube all the way down into the stomach, this is not always possible
so the catheter or feeding/dosing tube should be inserted as far as need
be to prevent the fluid from backing up and flooding into the glottis.
When expressing fluids or liquid nutrition (slurries) into a reptile,
do it slowly enough so that it flows down towards the stomach, rather
than so fast that it backs up into the mouth. If fluid or slurry backs
up into a reptiles mouth, stop forcing the fluid or slurry through the
tube. Tilt the reptile with its head downward to let the fluid or slurry
run out of his mouth and let him catch his breath.
For the most rapid
uptake of PO fluids, they should be warmed before being administered.
be injected directly into the body cavity. The advantage of administering
fluids in this way is that they are more quickly absorbed and more fluid
can be administered at one time than when giving fluids by mouth or subcutaneous
injection. The problem with this route of administration is that you need
to be shown how to do it, where to place the needle, and watch the slant
of the needle. If done incorrectly, you could puncture an organ or the
intestine. This is not something to attempt do to on your own without
first being shown how and without someone, initially at least, to restrain
the reptile for you so that you can concentrate on the injection itself.
A mark can be made on most reptiles, using povidone-iodine or even nail
polish (formaldehyde and tuolene free), around the injection site to help
you remember. Insert the needle between two scales, not through a scale.
the right side
of the lower abdomen to avoid the urinary bladder
the loose skin
cranial to the rear legs.
the lower third
of the body due to the need to avoid the lung(s).
means under the skin. The needle, held at a slant, is inserted between
the scales deep enough to get through the skin. The fluid is then expressed
slowly out of the syringe. If more fluid than can be injected at one site
must be administered, remove the needle and insert in another site. Preferred
sites for subcutaneous injections are:
in the loose
skin in the shoulder areas
the muscle groups along either side of the spine on the back and
the lateral midline of the body
Injections made in the
shoulder area need to avoid the neck (cervical) to avoid any damage that
could lead to neurological complications.
are most often injected Intramuscularly (in the muscle). Locations for
IM injections are:
in the muscle
groups in the front legs or in the muscles along the back and neck
in the muscle
groups in the front legs or in the muscles in the shoulder area
the muscle groups along either side of the spine on the back and
the lateral midline of the body
Choosing The Route
As can be
seen, different types of injections have different requirements: loose
skin, muscles, cavities. Not all reptiles are designed in the same way,
making one type of injection or another difficult or impossible. For example,
chameleons have very thin, poorly muscled legs, making it difficult to
give medications IM. Chameleons, anoles and day geckos tend to get very
highly stressed when handled, especially when handling is combined with
the pain of an injection. The injection itself can cause pain and discoloration,
and the psychological stress may lead to a worsening of the condition,
or at least a delay in recovery. On the other hand, it may be easier to
secure a venomous snakes head and administer an injection in the body,
than try to insert a pill or oral syringe into its mouth. When it comes
to a 15 foot crocodile with a serious attitude, it is easier to hide the
medication in a morsel of food and toss it to him.
Hiding oral medication
in food is certainly an option, but it should be the least amount of food
necessary to mask the medication. Food will interfere with the uptake
of the medication, so use this method only if absolutely necessary, and
don't top dress the reptile's usual meal with it. A small piece of fruit
or leafy green works for herbivores and omnivore. For omnivores and carnivores,
insert a pill into the mouth of a prekilled mouse, or inject the fluid
medication into the prekilled mouse's abdomen or mouth. Again, the prey
should not be meal-sized, just big enough for the predator to grab and
swallow. For insect and fish eaters, you will have to use a pill-pusher
or syringe with a feeding or dosing tube attached to give oral mediations.
The circulatory system in lizards and snakes is a bit different from
those in mammals. Fluids injected caudally (into the lower, or back, half
of the body, as from the abdomen down the tail) circulate first through
the kidneys then up to the upper part of the body. When medications are
injected caudally, they hit the kidneys in a less dilute form than if
they are injected cranially (in the upper, or forward, half of the body,
as from the ribs to the neck). Since many drugs, including antibiotics
(the most common drug administered to reptiles) are already known to be
nephrotoxic (harmful to the kidneys), it is important to reduce the impact
on the kidneys as much as possible. This can be done in two ways:
- inject drugs cranially
- inject extra fluids
(saline, Lactated Ringers), using subcutaneous or intracoelomic injections
When your veterinarian
prescribes injections, especially of antibiotics, discuss the need for
additional fluids and get from him the type you need and syringe and needles
for the injections.
In addition, all reptiles
under stress and undergoing any type of drug therapy should be kept well
hydrated, by administering oral fluids, ensuring fluids are available
for drinking and soaking (if there are no bandaging or casts that must
not get wet), and keeping the environment humidified for species native
to humid habitats in the wild.
To Mitigate Tissue Necrosis/Inflammation
can cause inflammation or necrosis of the tissue surrounding the injection
site. Signs include swelling of skin around site, blood or serous fluid
oozing from from the skin between the scales, pus forming at site, discoloration
of the skin, etc. This side effect can be mitigated by drawing some saline,
saline-dextrose, or lactated ringers up into the syringe. Discuss this
first with your vet. Many vets may be unaware of the side effect, especially
if their clients have not presented affected animals to them in the past.
Two drugs commonly associated with this effect are piperacillin (Piperacil)
and enrofloxacin (Baytril).
based on published
reports of veterinarians who have tried various doses in the course
of their own clinical practice
the minimum required
to sustain the basic functions of brain activity, heart and lung
the opening to
the trachea, found at the back of the tongue just above the esophagus;
it opens and closes as the reptile breathes (for drawing of glottis
in mouth, see Iguana
in the abdominal
in the abdominal
in the bone
conducted by veterinarian, researcher or drug company on the efficacy
of specific drugs and species
(per os) by mouth
SQ, subQ, SC
(under the skin)
in the body;
circulating in the body
Klingenberg, RJ. 1988. Anorexia in reptiles. Proceedings of the 12th
International Symposium on Captive Propagation and Husbandry. New York-New
Jersey Metropolitan Area, pp 621-634.
Mader, DM. 1991. Antibiotic therapy. In Frye, FL (ed.) Biomedical and
Surgical Aspects of Captive Reptile Husbandry, 2nd ed., Vol.
II. Krieger Publishing, Melbourne FL.
Jarchow, J. 1988. Hospital care of the reptile patient. In Jacobson E,
Kollias G Jr. (eds.) Exotic Animals. Churchill Livingstone, New York,
Frye, FL. 1991. Infectious disease. In Frye, FL (ed.) Biomedical and Surgical
Aspects of Captive Reptile Husbandry, 2nd ed., Vol. I. Krieger
Publishing, Melbourne FL.
Barnard, SM. 1996. Reptile Keeper's Handbook. Krieger Publishing, Melbourne
FL.. p. 191
fluids for reptiles. Veterinary Emergency Medicine PEARLS, Colorado
to administer fluid therapy in reptiles. Veterinary Emergency Medicine
PEARLS, Colorado State University
Barnard, Susan M. 1996.
Reptile Keeper's Handbook. Krieger Publishing Company, Malabar FL. 252
J. 1996. Therapeutics. In Mader, Douglas M. (ed.) Reptile Medicine and
Surgery, WB Saunders, Philadelphia PA, PP 301-302.
J. 1994. Basic principles of therapeutics used in reptile medicine. Proceedings
Association of Reptilian and Amphibian Veterinarians, Pittsburgh PA, October
Emergency Medicine PEARLS, Colorado State University.
in Reptiles - Guidelines for Offering Fluids FAQ,
by Tricia Power