Gastrointestinal parasites of black grouse Lyrurus tetrix: A long-term study (1986-2019) in the French Alps.

This study investigates the gastroenteric parasites community of 336 black grouse Lyrurus tetrix, covering a wide part of the totality of the species range in the French Alps and characterized by a long-term sampling (1986-2019). Parasite community was described using common epidemiological descriptors. Additionally, for the most prevalent parasite, a species distribution model (SDM) was built to understand the main factors influencing parasite occurrence. Ascaridia compar, Capillaria caudinflata, cestodes (Raillietina urogalli, R.cesticillus, and Hymenolepis microps), Eimeria sp. (E. lyruri and E.nadsoni), Corrigia corrigia and Acanthocephalus sp. The most prevalent species was C.caudinflata (P: 33%,CI95%: 28-38), whereas the lowest prevalence was recorded for Acantocephalus sp. (P:0.3%,CI95%:-0.3-0.9).The selected SDM for C.caudinflata includes only 3 variables: BIO11 (Mean Temperature of Coldest Quarter), the latitude of sampled animals and the distance from ski tour way. The distribution of C.caudinflata in the French Alps presents sharply defined areas where there are optimal environmental conditions for maintaining the life cycle of this parasite. These are the colder areas, characterized by higher latitude values and close to the ski tour ways. This study provides a valuable contribution to the scarce literature on wild Galliformes, describing the composition of the gastrointestinal parasite community of the black grouse.

Gastrointestinal parasitic infestation in the Rock ptarmigan Lagopus muta in the French Alps and French Pyrenees based on long-term sampling (1987-2018).

Data presented in this work represents the first record of parasites from the Alpine and Pyrenean Lagopus muta subspecies, providing valuable information to consider for conservation management. From 1987 to 2018, 207 Rock ptarmigans were collected in the framework of a long-term sanitary monitoring in France. Eight parasites were found in the Alpine Rock ptarmigan, and one in the Pyrenean subspecies. Only two parasites occurred with high prevalence in the Alpine Rock ptarmigan: Capillaria caudinflata (38.9%) and Eimeria sp. (34.7%). Prevalence of the other parasites (Ascaridia compar, Cestodes, Amphimerus sp. and Trichostrongylus tenuis) was lower than 20%. Dispharynx nasuta was found with a prevalence of 52.9% in the Pyrenean Rock ptarmigan. Overall, we found a spatially aggregated distribution of parasites in the northern French Alps, probably due to both favourable climatic conditions for parasite cycle and high host density. Statistical analyses indicated a positive effect of altitude and latitude on C. caudinflata occurrence whereas risk factors for Eimeria sp. were the distance from urban areas and land cover. In addition, the majority of the infested birds came from areas close to ski-pistes, where human disturbance increases the susceptibility to diseases, causing stress to wildlife.

Pestiviruses infections at the wild and domestic ruminants interface in the French Southern Alps.

In alpine pasture, interspecies transmission has recently been incriminated in the epidemiology of pestivirus infection. The aim of this study was to investigate pestivirus infections in wild and domestic ruminants sharing pastures in the French Southern Alps. Animal sera were screened for pestivirus antibodies against the pestivirus NS3 protein by a commercial blocking enzyme linked immunosorbent assay (ELISA). All 38 domestic herds tested were positive for pestivirus-specific antibodies. Individual sero-prevalence reached 76.5% (95% confidence interval [95% CI]: [74.2-78.8%]) of the 1383 sheep tested. For wild ruminants, 38.7% (95% CI: [33.8-43.9%]) of the 369 chamois tested, 28.7% (95% CI: [17.4-38.1%]) of the 72 roe deer, and 22.2% (95% CI: [6.5-37.9%]) of the 27 mouflons were seropositive. Virus screening was carried out on spleen samples from hunted wild animals (n=160) and from 15 domestic ruminants (clinically suspected to be persistently infected animals), by a conventional reverse transcription-polymerase chain reaction (RT-PCR). Three pestivirus strains were isolated from the sheep samples positive by RT-PCR. The viruses were classified in the BDV-3, BDV-Tunisian and BDV-6 genotypes. For the first time, one strain (RUPI-05 strain) was isolated from an alpine chamois and clustered in the BDV-6 genotype, showing in the 5'-UTR region 92% of identity with the ovine isolate from the same area. Thus, an active circulation of pestiviruses was demonstrated in both wild and domestic ungulates from the French Southern Alps. The results suggest that interspecies transmission between sheep and chamois probably occur.