A C Highfield
Tortoises which emerge from hibernation with health problems are in
serious - and immediate - danger. For a variety of biological
reasons, tortoises are at their most vulnerable at this time. In
particular, the white blood cell count is very low (thus reducing
their ability to fight infection), and the blood urea level is very
high due to metabolic toxins accumulated over the hibernation period.
This combination of low WBC and high blood urea, at a time when other
body functions are also not functioning at peak effectiveness does
mean that should anything go wrong, the time available to treat and
correct the problem is considerably less than normal.
There are several factors to consider in connection with hibernation. Each of these is critically important to the survival and well-being of the tortoise.
TEMPERATURE in hibernation.
Freezing is the biggest killer of hibernating tortoises by far. If the tortoises body temperature reaches freezing point at any time during the hibernation period, death or very serious injury will invariably occur. Do not make the mistake of believing that insulation alone will protect your tortoise - it won't. It merely slows up the rate of heat exchange. Prolonged spells of sub-zero temperatures will kill no matter how well insulated your tortoise is. The only way to offer complete protection is to use a reliable thermometer. If the temperature falls to dangerous levels, move the tortoise to a safe location at once. The ideal temperature for hibernation is circa 5oC.
DURATION of hibernation.
Tortoises in the wild typically hibernate for between 8-12 weeks. If you hibernate your tortoise for longer than this, then you are placing it as serious risk. The smaller the tortoise, the greater the risk (it's body fat reserves are less).
CONDITION of the tortoise.
Sick or underweight tortoises should never be hibernated. They will
not survive. Always perform a detailed pre-hibernation heath check to
ensure that the animal is a) up to a safe weight and b) is not
displaying any signs of disease. Sick or underweight tortoises will
need overwinter care indoors, with adequate light and heat to enable
them to function - and feed - normally.
The first thing tortoises really need to do on emerging from their
hibernation is to drink. Not only will they naturally be somewhat
dehydrated, but due to the accumulation of toxins during hibernation
the kidneys need a throughput of fluid in order to 'flush' these away.
The main waste is uric acid. This is a white, crystaline substance
which in a dehydrated animal looks a bit like thick emulsion paint or
even like powdery chalk. If a tortoise is allowed to become acutely
dehydrated, this substance can cause very serious damage to the
kidneys and the bladder. It is very important that it is flushed out
as quickly as possible. Drinking is therefore very much more important
at this stage than feeding.
a) A health problem,
b) A husbandry problem.
If your tortoise is not feeding by itself within one week of waking
up, do not delay - consult a veterinary surgeon who has particular
experience of reptile husbandry, physiology and treatment. Seek the
underlying cause of the problem,and do not be satisfied with
non-specific 'vitamin injection' therapy. There is always a logical
and very good reason for a tortoise persistently refusing to eat, and
generalised vitamin deficiencies are highly unlikely to be
responsible. Good diagnostic techniques, combined with an
understanding of reptile metabolism and function, will invariably
produce a satisfactory answer.
Most tortoises which are subjected to sub-zero conditions die as a result. Some, subject possibly to only peripheral freezing may survive however. These usually sustain at least some physical damage as a result.
The most commonly encountered problem is loss of vision due to the eyes freezing. The actual damage may involve the lenses or the retinas, and the consequences range from partial sight impairment to total blindness. A sight damaged tortoise behaves abnormally:-
TAKE THE TORTOISE TO YOUR VET IMMEDIATELY AND REQUEST AN OPTHALMIC TEST. USING AN OPTHALMASCOPE FROST DAMAGED EYES CAN USUALLY BE DIAGNOSED IMMEDIATELY.
The prognosis is very variable. Some cases recover completely reasonably quickly, other can take years. Some never recover. It very much depends upon the severity and extent of the damage sustained.
Emergency first aid
Dehydration is the most immediate danger. We use Hartmann's solution (an I.V drip compound sodium lactate) given orally at 5% of total bodyweight daily in cases of severe dehydration, reducing as urination begins and the electrolyte balance is restored. High doses of vitamin-A have definitely been shown to assist, particularly in cases of retinal damage and (to a lesser extent) in cases of cataracts on the lenses (ABIDEC is recommended).
Long-term care & maintenance
There are times when it may become necessary to resort to either force or hand feeding; particularly so in the case of sight damage or where a tortoise for some other reason is unable to feed itself. Fortunately tortoises do not find this as distressing as mammals, and from the owner's point of view the procedure is both safe and relatively simple. We classify force-feeding in three basic stages; hand-feeding, which is really no more than an encouragement to feed normally; syringe feeding, which is less time-consuming and where alternative foods can be employed; and finally, stomach-tube feeding, where semi-liquid food matter is introduced directly into the digestive system by means of a tube passed down the animal's throat.
Ideal in animals which are not in a serious condition, and where encouragement to take food into the mouth is all that is required. It is frequently highly successful with sight-damaged animals. Suitable foods: sliced apple, pears, cucumber and melon, lightly dusted with 'VIONATE' or 'ACE-HIGH'. Technique: simply open tortoises mouth, and place food within. To open a tortoise's mouth efficiently and safely, simply grasp animal firmly behind the ear-flaps and jaw with the thumb and second finger of one hand, and firmly force down the lower jaw with the thumb and first finger of the other hand.
Obtain a 5 ml or l0 ml syringe from your veterinary surgeon. Alternatively suitable syringes are often sold in pet stores as baby bird feeders. This method can be used in conjunction with the hand-feeding (above). Suitable foods: liquidised fruits - prepared baby foods are ideal. To these can be added 'VIONATE' or other vitamin supplements. Technique: open tortoise's mouth manually (as above), and simply syringe small quantities of food onto the tongue to be swallowed naturally.
This sounds more drastic and difficult than it actually is. However,
care must be taken a) not to cause physical damage, and b) not to
spread infection. To avoid the former proceed slowly and gently, to
avoid the second sterilise all implements thoroughly in 'MILTON' or
Obtain a 5 ml or l0 ml syringe, also a dog catheter. Cut to size and fix to end of syringe (length of tube = just over ® length of tortoise). Lubricate lightly with vegetable oil. Place tortoise in an almost vertical position, extend neck and head fully in a straight line. Gently and slowly pass tube down throat, carefully avoiding the trachea, which is located just behind the tongue. Gently and slowly empty the contents of the syringe into the tortoise.
The amount of food which should be introduced in this fashion has been the subject of some confusion. Our general recommendations are as follows. These figures have been extracted from our case records based upon several hundred animals and we believe them to be highly accurate. Sometimes figures are quoted which are many times in excess of these,but we believe that such over-feeding can prove extremely hazardous, especially to a sick or relatively inactive animal.
IMPORTANT: Note that dog and cat (meat-based) foods must under NO CIRCUMSTANCES be given to mediterranean tortoises which are natural herbivores. In the wild these animals eat herbs, grasses and 'weeds'; the protein and fat content of these is low. Tortoises kidneys are not able to deal with the very much higher blood urea levels produced by digesting high protein foods. The liver of tortoises is similarly unable to cope well with high fat diets.
The products 'VIONATE', 'ACE-HIGH' and 'NUTROBAL' are special mineral supplements which are available from some veterinary surgeons, or in cases of difficulty, by mail-order from the Tortoise Trust. The product 'ABIDEC' is a high potency vitamin-A supplement available from most High Street chemists.
© 1994 The Tortoise Trust