STRONGYLID NEMATODES SHARED BETWEEN DOMESTIC AND WILD RUMINANTS IN MAIELLA NATIONAL PARK (ABRUZZO REGION - CENTRAL ITALY) B PAOLETTI1, S ANGELUCCI2, S MORELLI1, C SMOGLICA1, A BARLAAM1, A DI CESARE1 1Faculty of Veterinary Medicine, University of Teramo, 64100 Italy; 2Maiella National Park, Via del Vivaio snc, 65023 Caramanico Terme, Italy Keywords - Strongyles, Ruminants, Maiella National Park, Central Italy INTRODUCTION. Strongylid nematodes (SN) are recognized as a major constraint to livestock production. The control of SN relies heavily on the use of chemotherapeutics; as a consequence, anthelminthic resistance (AR) is increasing (Barone et al., 2020). It is known that wild ruminants are competent hosts of a number of SN that typically infect livestock and it is assumed that they could also act as reservoirs in the translocation of anthelmintic resistance (Chintoan-Uta et al., 2014). This risk is heightened where the pasture of domestic and wild ruminants overlaps. The aim of the present study was to obtain novel information on the distribution of SN in sheep and wild ruminants (i.e., red deer, chamois) sharing the same pasture in the Maiella National Park. MATERIALS AND METHODS. In 2019, a total of 20 faecal pool samples were collected from sheep (n. 7) and wild ruminants (n. 13) (Figures 1, 2, 3) that shared the same pasture in the highlands of the Maiella National Park (Abruzzo region, central Italy). The samples were examined by a classic copromicroscopic technique (Euzeby, 1981). Gastrointestinal strongyle (GIS) positive pools were subjected to coprocolture (MAFF, 1986) (Figure 4). L3s were morphologically and molecularly identified (Gasser et al., 1993; van Wyk et al., 2013). Figure 1: Sheep flock in the Maiella National Park RESULTS AND CONCLUSIONS. Thirteen faecal pools were positive for GIS and 16 pools for bronchopulmonary strongyles (PBS) (Table 1). The results of this study confirm that domestic and wild ruminants studied in the Maiella National Park share most of the gastrointestinal and bronchopulmonary strongyle species. The helminthofauna of gastrointestinal strongyles was dominated by H. contortus, Tel. circumcincta and T. colubriformis (Figure 4) typical species of domestic ruminants that have been reported in cervids and wild bovids sharing pastures with cattle and sheep (Zaffaroni et al., 2000). Muellerius capillaris was the dominant lungworm species. Figure 2: Chamois in the Maiella National Park Further studies are required to investigate the pattern of transmission of strongyles between domestic and wild ruminants and the role of wildlife in the spread of anthelmintic-resistant nematodes. The study was carried out in the framework of the Project “Demetra” [Dipartimenti di Eccellenza 2018-2022, CUP_C46C18000530001], funded by the Italian Ministry for Education, University and Research Figure 3: Red deer in the Maiella National Park Parasite Sheep Wild ruminants Morph. Id. Molec. Id. Morph. Id. Molec. Id. Haemonchus contortus yes yes yes yes Teladorsagia circumcincta yes yes yes yes a Trichostrongylus colubriformis yes yes yes yes Oesophagostomum spp. yes yes yes no Oesophagostomum venulosum no yes no yes a a bb Chabertia ovina yes yes no no Ostertagia-type group no n.d. yes n.d. a Ostertagia leptospicularis no no no yes Muellerius capillaris yes n.d. yes n.d. c c d d ee Neostrongylus linearis no n.d. yes n.d. Figures 4: a) coprocolture; b) posterior end of a third stage larva of Haemonchus contortus; c) third stage Table 1: Results of larval identification of L3 (GIS) and L1 (PBS) found in at least one faecal pool. Morph. Id.: Morphologic Identification; Molec. Id.: Molecular larva of Trichostrongylus colubriformis; d-e) anterior and posterior ends of a third stage larva of Identification; n.d.: not determined. Teladorsagia circumcincta. REFERENCE. Barone et al., 2020. Vet Parasitol. 279: 109041; Chintoan-Uta et al., 2014. Proceedings of the Royal Society B: Biological Sciences 281 (1780):20132985; Euzeby, 1981. Livre 1, Informations Techniques des Services Vétérinaires, Paris, France, pp. 195-214; Gasser et al., 1993. Nucleic Acids Research 21 (10): 2525-2526; MAFF—Ministry of Agriculture, Fisheries and Food. 1986. 3rd ed. HMSO Books, London, U.K., p. 159; van Wyk et al., 2013. Onderstepoort J Vet Res. 80: 539; Wyrobish-Papiewska et al, 2021. Animals 11: 182; Zaffaroni et al. 1997. Parassitologia 39: 313–317; Zaffaroni et al., 2000. Veterinary Parasitology 90: 221–230..