Non-Invasive Wildlife Disease Surveillance Using Real Time PCR Assays: The Case of the Endangered Galemys pyrenaicus Populations from the Central System Mountains (Extremadura, Spain)

SIMPLE SUMMARY: Until now, data on parasites or bacteria of the Iberian desman (Galemys pyrenaicus) was practically absent. We used non-invasive methods of sample collection and analysis to determine the health status of G. pyrenaicus. We detected four species of bacteria and three parasites using qPCR assays. Based on DNA sequence data, G. pyrenaicus in the study area harbors a likely new species of the previously monotypical genus Omphalometra. ABSTRACT: The Iberian desman (Galemys pyrenaicus) is a small semi-aquatic mammal that inhabits mountainous areas from the centre to the north of the Iberian Peninsula and the Pyrenees and is listed as endangered because it has suffered a serious decline. Since 1960, only three species of digeneans (Omphalometra flexuosa, Maritrema pyrenaica and Mathovius galemydis) and two nematodes (Aonchotheca galemydis and Paracuaria hispanica) have been reported from the desman, but no further information on health status and no data from Extremadura has been available. The aim of our study was to characterise the diversity and distribution of parasites and microbiomes of desmans in different areas of the Central System of Extremadura. Between 2019 and 2021 we collected 238 fecal samples and one tissue (intestine) sample that was obtained from a dead desman. DNA templates were processed by commercial or customised real-time PCR using TaqMan probes. Representative data were obtained for Cryptosporidium spp., Omphalometra spp., Eimeria spp., Salmonella spp., Staphylococcus spp. and Leptospira spp. Omphalometra spp. was studied using a newly developed PCR test. The screening of the dead desman allowed us to obtain, for the first time, a partial sequence of the 18SrDNA. This study is the most complete study of the desman, allowing us to identify parasites and the microbiome in populations of G. pyrenaicus using non-invasive sampling.