Vitamin A is one of the fat soluble vitamins and is a vital building block for healthy tissues. If a reptile does not have enough vitamin A, it cannot repair and maintain its eyes, skin, mucous membranes (for example the inside of the mouth) and ducts (for example tear ducts but more importantly endocrine ducts and the tubules in the kidneys). This can be catastrophic for the animal and if left untreated, the lizard will certainly die.
Early Signs of Hypovitaminosis A
Mainly because of the problems which the animal will be having with tear ducts and the mucous membranes lining the eyelids, one of the first signs that a lizard has hypovitaminosis A will be a swelling of the eyelids. This is sometimes so pronounced that the animal will be unable to open its eyes. Although this is one of the main conditions causing eye problems, it is nonetheless imperative that the lizard is seen by a vet. It is important not to try and medicate the animal yourself. As this is just the first sign of a progressive condition, the next stage could be problems with pancreas, liver and kidneys and once the stage of the involvement of these vital organs is reached, recovery is unlikely.
Causes of Vitamin A Deficiency in Lizards
Lizards which are being fed an all meat diet or a poor quality commercial feed are at grave risk of developing vitamin A deficiency, as meat is very low in naturally occurring vitamin A. It is vital to also provide your lizard with a supplement to bring the levels of this important antioxidant up to acceptable levels. Vitamin A levels have a narrow window of optimum dose. Too little results in the symptoms and outcome above; too much is toxic and can kill the animal very quickly, so following the dosage is very important.
Correcting the Imbalance
The species of lizard will clearly have a huge bearing on balancing its vitamin A, because it will have different needs depending on its natural food source, whether it is carnivore, vegetarian or omnivore. Your vet will give you guidance on what the dose should be. If the levels are dangerously low, but no internal damage has yet resulted, the vet will probably put the lizard on a carefully balanced diet, with supplements, but with a kick start of an injection.
If this has been given it is very important not to give Ďa drop for luckí of the vitamin as toxicity is a very small step away from cure. A diet rich in dark green vegetables (not iceberg lettuce, as it has virtually no vitamin A at all), meat protein and a good quality commercial food in appropriate quantities will prevent recurrence.
Other Problems that may occur with Hypovitaminosis A
Alongside vitamin A deficiency, your lizard may present with other secondary problems. These are likely to include skin and mouth infections and depending on their nature and their severity, the vet will prescribe a general antibiotic or fungicide, to control them while the nutrition is improved. When any animal is inadequately nourished, their immune defences are at a very low ebb and it is all too easy for opportunistic bacteria to gain a hold. Where vitamin A deficiency has resulted in eye problems the dry eyes and gummy secretions from the tear ducts are good breeding grounds for staphylococcus which would otherwise be harmlessly present on the skin.
General care until Nutrition is Improved
While waiting for the vitamin A to be reabsorbed by the lizardís tissues and start repairing mucous membrane and duct damage, it is vital to take extra special care of the animal. Alongside the fungicidal and antibiotic creams and oral dosing, the environment of the animal must be given extra thought and care. If the animal in question is the only lizard in a group to be affected Ė perhaps brought in more recently or off its food for physical reasons - it is a good idea to isolate it from the rest, especially if it has broken skin or very bad eye problems. This way, it can be dosed more precisely and also a check can be made regularly for any worsening of its general wellbeing or any skin lesions.
General Nutrition and the Prevention of Vitamin A Deficiency
It is likely that the lizard deficient in vitamin A will also be lacking other vitamins, most commonly vitamin E and trace elements such as zinc. Vitamins A, E and some trace elements are very labile (they break down easily with age) and so if the commercial food being fed is not totally fresh, the advertised levels of these are not any longer accurate. This might mean that although to all intents and purposes the right nutrition is being given, it is not actually so.
A Healthy Diet for your Lizard
Your vet will ask searching questions regarding your lizardís nutrition and it is helpful if a food diary can be provided, along with batch numbers and expiry dates of any commercial food. Fresh vegetables also lose their vitamin content quickly and if they are wilted or discoloured, much of their goodness is gone. It is possible to buy quite cheaply vegetable bags to use in the fridge, which keeps leafy vegetables fresh for longer. If your lizard is the only creature in the house that will eat his spinach, you might like to invest in some of these bags, so that a portion bought from the supermarket is not totally de-vitamin and mineralised by the time it is fed to your lizard.
With modern irradiation of many foods, they still look quite wholesome for long after their natural shelf life and so it is easy to be misled into thinking that the diet you are providing is balanced when it is not.