Reptile - Dysecdysis

What is dysecdysis?

Dysecdysis describes the failure to shed skin properly.

All reptiles grow by shedding their skins periodically. In the case of snakes the old skin is normally shed intact while in lizards and the scaled skin of chelonia it flakes off in pieces..

Chelonian (eg tortoise) shell is either shed into water or, in the case of terrestrial species, is retained on the shell producing growth rings..

The process by which skin is shed and replaced is complex – as new skin is produced so a fluid is produced between old and new layers (hence the milky appearance of snakes due to shed) before the old layers lift and are rubbed off.

As with any complex process, it can easily go wrong!

Failure to shed properly can be due to a number of problems:

Environmental

• Low temperature
• Inappropriate heating
• Low humidity
• Nowhere to rub against

Internal

• Dehydration
• Parasitism (internal or external)
• Underlying internal disease

Dysecdysis cases must, therefore, be thoroughly investigated as failure to understand the underlying problems will result in treatment failure.

While investigating these, the shedding problem itself can be relieved by bathing the reptile daily and by gently rubbing the affected areas with damp warm towel. Retained sheds should not be pulled off unless they are very loose and lift away with ease.

Special attention should always be paid to the eyes, feet, tail tip, edge of the mouth and sensory pits.

There are two particular problems associated with dysecdysis:

1. Retained spectacles in snakes. Snake eyes are covered in skin (clear 'spectacles') and so shed with the rest of the skin. Failure to shed these produces thickened wrinkled opaque coverings to the eye. The snake will often be bad tempered and have trouble feeding as it will have trouble seeing. On no account should the retained layers of skin be pulled off – this can lead to eye damage and permanent blindness. Instead, the spectacles should be gently bathed each day until they lift away. In some cases this will not be until the next shed. Underlying health and environmental problems must also be addressed.
2. Eye problems in Leopard Geckos. These do not have spectacles but do have skin on the inside of the eyelids. Dysecdysis will, therefore, cause eye problems with irritation generally resulting in conjunctival abscesses. This species is also prone to retained sheds constricting on the feet causing loss of digits. Why? They are a desert species and so are normally kept in hot dry vivaria – however, in the wild these geckos live under rocks where there is 100% humidity! Therefore they must be provided with a humidity chamber in order to shed properly. This should consist of a margarine tub with the lid on and a 'door' cut out of the side. The inside is filled with damp sphagnum moss that is changed regularly. It is also important that the vivarium is not heated by means of a heat mat under the substrate – this appears to increase the drying of the feet making dysecdysis more likely.