Endoparasites infecting exotic captive amphibian pet and zoo animals (Anura, Caudata) in Germany

Alongside exotic reptiles, amphibians, such as toads, frogs, salamanders, and newts, are nowadays considered popular pets worldwide. As reported for other exotic pet animals, amphibians are known to harbor numerous gastrointestinal parasites. Nonetheless, very little data are available on captive amphibian parasitic diseases. In this study, we applied direct saline fecal smears (DSFS) to examine in total 161 stool samples from 41 different amphibian species belonging to the orders Anura and Caudata. In addition, carbolfuchsin-smear (CFS) staining (n = 74 samples) was used to detect amphibianCryptosporidiumoocysts. Also, complete dissections of deceased amphibians (n = 107) were performed to specify parasite infections and to address parasite-associated pathogenicity. Overall, examined amphibian fecal samples contained 12 different parasite taxa. The order Rhabditida with the speciesRhabdiasspp. andStrongyloidesspp. were the most prevalent nematode species (19.3%), followed by flagellated protozoans (8.7%),Amphibiocapillariaspp./Neocapillariaspp. (7.5%),Oswaldocruziaspp. (4.3%),Blastocystisspp. (3.1%),Cosmocercaspp. (3.1%), oxyurids (Pharyngonoidae) (3.1%), spirurids (1.2%), un-sporulated coccidian oocysts (0.6%),Tritrichomonasspp. (0.6%),Karotomorphaspp. (0.6%), andCryptosporidiumspp. (0.6%). One CFS-stained fecal sample (1.4%) was positive forCryptosporidiumoocysts. Within dissected amphibians, 31 (48.4%) of the anurans and 11 (26.2%) of the salamanders were infected with gastrointestinal parasites. One cutaneousPseudocapillaroides xenopiinfection was diagnosed in an adult African clawed frog (Xenopus laevis). Etiologically, 17 (15.9%) of them died due to severe parasitic and/or bacterial infections (e.g.,Chryseobacterium indologenes,Citrobacter freudii,Sphingobacterium multivorum,Klebsiella pneumoniae). High prevalence and pathological findings of several clinical amphibian parasitoses call for more detailed investigation on gastrointestinal parasite-derived molecular mechanisms associated with detrimental lesions or even death.