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bioRxiv · 10.1101/2025.07.27.667008

Changes in housing and diet combined increase fecal Oxyurid load in captive tokay geckos

Gliga, D. S.·Szabo, B.
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Abstract

Reptiles are increasingly popular as exotic pets and suffer high mortality especially in the first year in captivity, yet research into their welfare remains limited. Reptiles are often infected by parasites. One common taxon is Oxyuroidea superfamily, which has a direct life cycle that promotes easy transmission in enclosed environments. Due to limited ecological knowledge, inappropriate husbandry practices are common in reptiles causing stress and increased parasite loads leading to severe health issues. Therefore, it is crucial to understand how routine captive procedures may influence parasite infections. In this study, we exposed captive bred tokay geckos (Gekko gecko) to two stressors common in the reptile trade, cohabitation with a novel conspecific and a change in diet. We tested their effect on fecal oxyurid output compared to a control group as well as their combined effect. We found that a single stressor had no effect on fecal parasite load while both combined did significantly increase parasite load. However, we did not find a detectable change in the lizards general condition. Our study shows that seemingly minor changes in housing and husbandry can exert stress and increase parasite load in tokay geckos. Further studies are needed to determine which other procedures (e.g. confinement, transport, novel environments) affect health and when combined could lead to more severe changes in health in reptiles. SummaryMany reptiles are infected with parasites that can lead to health issues. Routine husbandry procedures such as new conspecifics and diet are stressful and lead to a higher parasite load in geckos.

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Gliga, D. S., Szabo, B.. 2025-07-31. Changes in housing and diet combined increase fecal Oxyurid load in captive tokay geckos. https://doi.org/10.1101/2025.07.27.667008

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