Abstract

In zoos, free-ranging animals may go beyond barriers segregating captive breeding stock thereby increasing the risk of transmission of infectious agents. In order to assess the role of free-roaming geckoes (Gecko monarchus, Gehyra mutilata), in the epidemiology of infectious diseases in the Reptile House of Jersey Zoo, a bacteriologic, parasitologic, and virologic screening of 32 free-roaming geckoes was conducted. The animals were caught from exhibit and non-exhibit rooms where they had free access to by open doors and the ventilation system. Blood samples by cardiocentesis were taken under anaesthesia (isoflurane 5%) and pooled of two to four animals to obtain enough serum to be tested for ophidian paramyxovirus (OPMV-1, OPMV-7) by haemagglutination inhibition. After euthanasia by pithing, a complete postmortem examination was conducted. Bacterial cultures of intestines, liver, and any organs showing abnormalities were done. Parasitologic examinations of intestinal content were conducted by microscopy of direct smears, sporulation of coccidia in potassium dichromate 2.5%, and Ziehl-Neelsen staining. Apart from physiologically occurring enterobacteria and protozoa, cryptosporidia could be identified. In addition, 70% of pooled blood samples tested positive for ophidian paramyxovirus (OPMV-1, OPMV-7). More detailed investigations would be necessary to prove the definite vector role of the geckoes in specific diseases. They can, however, increase prevalence of opportunistic agents and exposure of the captive breeding stock to diseases and should be taken into account when dealing with infectious disease problems in captive reptile collections.

Acknowledgments

The author would like to thank A. Allchurch, BVSc, MRCVS, and A. Thomasson for the generous support to realize this paper as a product of a work placement student project at the Durrell Wildlife Conservation Trust.