Reduction in Cetacean Pox (Tattoo) Lesions with Water Temperature Elevations
Cetacean tattoo lesions are circular to irregular gray skin lesions with black stippling that can occur anywhere on the body.1 Tattoo lesions are caused by cetacean poxviruses which are in the Chordopoxvirinae family and most closely related to the Orthopoxvirus genus.2 Tattoo lesions have been very commonly reported (most studies report > 60% affected) in both free ranging and zoologically maintained dolphin populations. Documented reports of tattoo lesions encompass multiple species of odontocetes and represent widespread global distribution.3,4,5 Signalment (especially age), environmental factors (including temperature and salinity), anthropogenic impacts (contaminant levels), and general health of the animal have all been suggested to influence prevalence and expression of tattoo lesions.1,3,4,5
This study documented significant decrease in expression and appearance of tattoo lesions in bottlenose dolphins in 5 different facilities/water systems following increase in water temperature from 21–24°C (70–75°F) to 25.5–26.5°C (78–80°F). Over 40 dolphins were closely monitored with behavioral observation, photodocumentation of skin, veterinary exam and routine blood analysis. Study animals included both males and females, including pregnant females, with ages ranging from 2 to > 40 years. Reduction in tattoo lesions could be noted as early as 2–3 weeks following temperature change. Marked reduction to complete resolution of tattoo lesions was seen 5–6 weeks post temperature increase. Dolphins started showing signs of satiation (playing with fish) between 5 and 6 weeks following temperature change requiring ∼10% reduction in food base. Routine blood parameters (CBC, serum chemistry panel, fibrinogen, ESR) remained static suggesting no changes in overall health of the animals. When water temperatures were dropped again, tattoo lesions began to recur within approximately 1 month.
Our results suggest that water temperature is the predominant factor in expression of tattoo lesions in bottlenose dolphins. Decisions regarding desired temperature range at dolphin facilities will have to factor in energy costs and capabilities for heating water as well as increased maintenance efforts to keep algae growth at bay.
The authors wish to thank the Animal Care, Animal Training, Water Quality, and Veterinary Services staff of The Mirage, SeaWorld Orlando, and Discovery Cove. Special thanks go out to David Blasko and Erin Wise at the Mirage; Victor Marsich, Jay Tacey, Kym Folkemer, Jesse Pottebaum, Kelly Flaherty Clark, Iulia Siemen, Jacob Vandenberg, Scott Gearhart, Michelle Davis, Stacy DiRocco, Carmen Peccie, Jayne Hutcheson, and Danielle Gaucher at SeaWorld and Discovery Cove.
* Presenting author
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