Natural exposure to ultraviolet‐B radiation in two species of chameleons from Madagascar

Managing the Health of Captive Groups of Reptiles and Amphibians

Managing the health of reptile and amphibian collections is centered on providing appropriate environmental parameters, husbandry conditions, and nutrition as well as maintaining good welfare and careful collection planning. Disease transmission is reduced through quarantine, appropriate diagnostic testing, and annual veterinary health assessment."

Is the natural UV zone important for successful captive propagation of the Panther Chameleon (Furcifer pardalis); are different UVB irradiance exposures that generate a similar dose equally successful?

While we generally understand the optimal ultraviolet B (UVB) environment for the growth and reproduction of female Panther Chameleons Furcifer pardalis, we do not know the relative importance of UVB irradiance and dose for optimal husbandry outcomes. Accordingly, we experimented with Panther Chameleon females to test the hypothesis that UVB dose (irradiance × exposure duration) determines the outcome, regardless of the combination of UVB irradiance and exposure duration generating the dose. We varied UVB irradiance and exposure duration across treatment groups while keeping dose similar and within a range previously documented to result in reproductive success. The growth rate, age of maturity, and measurable vitamin D status were not significantly different among the treatment groups. Individuals in all groups produced viable eggs that successfully hatched. Thus, we found some support for the hypothesis that the UVB dose determines the outcome regardless of UVB irradiance. However, mean egg vitamin D₃ concentration and percent hatching were higher in the highest UVB irradiance group, despite similar doses among the three groups. Preliminary field data reveal that this species occupies UV irradiance Zone 4 in Madagascar, the highest zone for reptiles recorded. Only the irradiance of the high UVB irradiance group in our experiment approached this zone and resulted in the best reproductive success. Biosynthesis of vitamin D₃ and provisioning to eggs is more efficient when exposure to UVB irradiance is similar to that in their natural environment. Establishing an optimal UVB environment, based on knowledge of the natural UVB environment, is important for the propagation of Panther Chameleons in captivity.

Cheilitis Associated with a Novel Herpesvirus in Two Panther Chameleons (Furcifer pardalis)

Intracellular epidermal inclusions were detected within histological sections of skin biopsies from two panther chameleons (Furcifer pardalis) with chronic cheilitis. Transmission electron microscopy (TEM) confirmed the abundant presence of icosahedral intracytoplasmic and intranuclear viral particles in infected keratinocytes, with an average diameter of 120-125 nm, consistent with herpesviruses (HVs). TEM also revealed the presence of virions in intercellular spaces and keratinocyte nuclei and features suggestive of capsid assembly, nuclear egress with primary envelopment and anterograde transport leading to virion assembly and release. Polymerase chain reaction (PCR) primers targeting a conserved region of herpesvirus DNA-dependent DNA polymerase were used to amplify and sequence a product from a nested HV PCR performed on skin biopsies of both chameleons. Comparative sequence analysis indicates that the virus detected in both chameleons was a novel member of the Alphaherpesvirinae, which we refer to as chamaeleonid herpesvirus 1 (chamHV 1). Based on the identical findings in both chameleons, we consider chamHV 1 to be a candidate aetiological agent of cheilitis in panther chameleons. This is the first report of skin lesions in a chameleon species associated with HV infection.