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Samples are preserved in the CBGP—Small mammal collection (https://doi.org/10.15454/WWNUPO) and referenced in the associated Small Mammal Database. Molecular data necessary for helminth identification were generated at the molecular biology platform of the CBGP.; International audience; Previous field-based studies have evidenced patterns in gastrointestinal helminth (GIH) assemblages of rodent communities that are consistent with “enemy release” and “spill-back” hypotheses, suggesting a role of parasites in the ongoing invasion success of the exotic house mouse (Mus musculus domesticus) in Senegal (West Africa). However, these findings came from a single invasion route, thus preventing to ascertain that they did not result from stochastic and/or selective processes that could differ across invasion pathways. In the present study, we investigated the distribution of rodent communities and their GIH assemblages in three distinct zones of Northern Senegal, which corresponded to independent house mouse invasion fronts. Our findings first showed an unexpectedly rapid spread of the house mouse, which reached even remote areas where native species would have been expected to dominate the rodent communities. They also strengthened previous insights suggesting a role of helminths in the invasion success of the house mouse, such as: (i) low infestation rates of invading mice by the exotic nematode Aspiculuris tetraptera at invasion fronts—except in a single zone where the establishment of the house mouse could be older than initially thought, which was consistent with the “enemy release” hypothesis; and (ii) higher infection rates by the local cestode Mathevotaenia symmetrica in native rodents with long co-existence history with invasive mice, bringing support to the “spill-back” hypothesis. Therefore, “enemy release” and “spill-back” mechanisms should be seriously considered when explaining the invasion success of the house mouse—provided further experimental works demonstrate that involved GIHs affect rodent fitness or exert selective pressures. Next steps should also include evolutionary, immunological, and behavioral perspectives to fully capture the complexity, causes and consequences of GIH variations along these invasion routes.

A survey of the presence of yeasts in frogs and toads in Thailand was conducted using standard mycological examination techniques. The results, which were confirmed with molecular techniques, revealed the presence of five yeast species – Cryptococcus liquefaciens, C. heveanensis, Pseudozyma hubeiensis, Rhodotorula mucilaginosa and R. minuta – in the bile of these amphibians. Although previous works have isolated yeasts from amphibian gastrointestinal tracts and skin, it is questionable whether these yeasts were acquired by ingestion or were commensals on adult individuals. Frog farms, an urban area and protected natural areas were surveyed and all tested positive for yeasts, which shows their ubiquity in both wild and farm-reared frogs. Additionally, the finding of yeasts in five different species of frogs and toads shows that there is a wide spectrum of hosts in this vertebrate group. Our results thus suggest that yeasts are likely to be widespread among amphibians in different habitat types and in a wide range of host species., Acta Herpetologica, Vol 11 No 1 (2016)

Pancreatitis associated with the helminth Serpinema microcephalus was found in three of 19 free-ranging red-eared slider turtles (Trachemys scripta elegans) captured between March 2003 and September 2004 in southern Spain. Microscopic changes were associated with parasite migrations and were characterized by central areas of necrosis surrounded by leukocytes and resulted in destruction of exocrine tissue. The blood profile of one of the three female turtles revealed eosinophilia and hyperglycemia, common in helminth infections and pancreatic disorders respectively. These are the first reported cases of pancreatitis caused by the nematode S. microcephalus in the exotic and newly colonized host T. s. elegans. © Wildlife Disease Association 2011.