Pigment changes in Reptiles | Vetlexicon
reptile - Articles

Pigment changes

Contributor(s) :


Introduction

  • Cause: normal age-related change in certain species, response to environmental stimuli, dysecdysis, trauma related changes, scarring, thermal burns, bacterial/fungal dermatitis, gray patch disease in turtles.
  • Signs: pigment changes may go unnoticed for a while – these may take place as a normal age-related change in certain species such as green tree pythons or be a result of illness/trauma/disease. They may start off anywhere on the body and become progressive, eg thermal burns in reptiles will progress within a few days of the initial injury.
  • Diagnosis: based on clinical signs and history. Cytology, culture and sensitivity, biopsy may be needed if a disease process is suspected.
  • Treatment: dependent on underlying cause. Most pigment changes are of cosmetic consequence only.
  • Prognosis: good to guarded depending on underlying cause.

Presenting signs

  • Dependent on underlying cause, pigment changes may either take place slowly and go unnoticed or occur rapidly in response to trauma.
  • If a disease process such as fungal disease is responsible for pigment changes, this may be accompanied by non-specific signs such as lethargy and anorexia.

Acute presentation

  • If pigment changes take place in response to trauma, bleeding, sloughing of skin and discharge.
  • Chronic pigment changes may be associated with dysecdysis.

Geographic incidence

  • Worldwide.

Breed/Species predisposition

  • Some pigment changes are normal in certain species such as green tree pythons (Morelia viridis) Green tree python:
    • Juveniles present in two color morphs: bright yellow and brick red and progress to vibrant green as they age.
    • This reflects the adaptive changes in response to a change in diet and habitat in their natural environment.

Public health considerations

  • Many species of reptiles are natural carriers of Salmonella which is of zoonotic potential to humans.

Cost considerations

  • Initial consultation.
  • Sedation/general anesthesia may be needed for swabbing of aggressive or venomous species/collection of cytology samples/biopsy.
  • Ongoing treatment if a disease process is responsible for the pigment changes.

Pathogenesis

Etiology

  • Pigment changes take place in certain species as a response to diet and habitual changes; this is because of altered pigment cell number or the amount of pigment within cells.
  • Skin color changes are a long-recognized phenomenon in chameleons (Family: Chamaeleonidae):
    • It occurs as a response to external stimuli such as temperature or stress and is thought to help with communication within individuals.
    • In response to these stimuli, the pigment-containing cells chromatophores will relax or contract shifting the distribution of contained pigment and altering the external appearance of the animal.

Predisposing factors

General

Specific

  • Environmental temperatures should be strictly controlled for poikiliotherms and checked daily .
  • Thermal injuries Burn injuries are frequently seen in snakes that wrap themselves around unprotected heat sources.

Timecourse

  • Thermal burns Burn injuries may not be evident for several days post-injury.

Diagnosis

Subscribe To View

This article is available to subscribers.

Try a free trial today or contact us for more information.

Treatment

Subscribe To View

This article is available to subscribers.

Try a free trial today or contact us for more information.

Prevention

Subscribe To View

This article is available to subscribers.

Try a free trial today or contact us for more information.

Outcomes

Subscribe To View

This article is available to subscribers.

Try a free trial today or contact us for more information.

Further Reading

Publications

Refereed Papers

  • Recent references from PubMed and VetMedResource.
  • Wilson D, Heinsohn R & Endler J (2007) The adaptive significance of ontogenetic colour change in a tropical python. Biol Lett 3 (1), 40-43 PubMed.

Other sources of information

  • Scheelings T (2019) Anatomy and Physiology. In: BSAVA Manual of Reptiles. BSAVA, UK. pp 1-26.