Sarcocystis infection in red deer (Cervus elaphus) with eosinophilic myositis/fasciitis in Switzerland and involvement of red foxes (Vulpes vulpes) and hunting dogs in the transmission

Abstract

Red deer ( Cervus elaphus ) carcasses showing grey-greenish discolouration have been increasingly observed in the canton of Grisons, Switzerland. We investigated whether Sarcocystis infections were associated with this pathology, and whether wild and domestic canids were involved in their transmission. Meat from affected red deer ( n = 26), faeces and intestines from red foxes ( Vulpes vulpes ) ( n = 126), and faeces from hunting dogs ( n = 12) from the region, were analysed. Eosinophilic myositis and/or fasciitis were diagnosed in 69% of the deer, and sarcocysts were observed in 89% of the animals. Molecular typing targeting a ~700bp variable region of the 18S rRNA gene revealed Sarcocystis hjorti in 73%, S. venatoria/S. iberica in 54%, S. linearis/S. taeniata in 12%, S. pilosa in 8% and S. ovalis in 4% of the deer samples. No inflammatory changes were observed in red deer carcasses with normal appearance ( n = 8); however, sarcocysts were observed in one sample, and S. hjorti , S. venatoria/S. iberica or S. silva DNA was detected in five samples. Sarcocystis oocysts/sporocysts were observed in 11/106 faecal and 6/20 intestinal fox samples, and in 2/12 canine samples. Sarcocystis tenella ( n = 8), S. hjorti ( n = 2), S. gracilis ( n = 2), and S. miescheriana ( n = 1) were identified in foxes, and S. gracilis ( n = 2), S. capreolicanis ( n = 1) and S. linearis/S. taeniata ( n = 1) in dogs. This study provides first molecular evidence of S. pilosa and S. silva infection in red deer and S. linearis/S. taeniata in dogs and represents the first record of S. ovalis transmitted by corvids in Central Europe. Although Sarcocystis species infecting red deer are not regarded as zoonotic, the affected carcasses can be declared as unfit for human consumption due to the extensive pathological changes.

The Role of Mustelids in the Transmission of Sarcocystis spp. Using Cattle as Intermediate Hosts

“…Usually, molecular analysis is performed when oocysts/sporocysts of Sarcocystis spp. are microscopically detected in intestine mucosal or faecal samples [ 2 , 29 , 30 , 31 ]. However, the results of the present study reveal that molecular methods should be applied in testing all examined samples rather than only microscopically positive ones.…”

“…Recently, molecular methods have been applied for the identification of Sarcocystis spp. from fecal or mucosal scraping samples of various wild predators or scavengers infected under natural conditions [ 2 , 29 , 30 , 31 ]. The present work is the first study of the molecular identification of Sarcocystis spp.…”

Dogs are final hosts of Sarcocystis morae (Apicomplexa: Sarcocystidae): First report of this species in Hungary and its region – Short communication

“…In particular, it has long been postulated that red foxes and hunting dogs may play the final host role in the life cycle of Sarcocystis species affecting cervids, but for several species the exact final hosts are still unknown or are only suspected (Basso et al, 2020). In this context, based on molecular results and less consistent (98.8-99.1%) sequence identities, it was suggested that domestic dogs may be the final hosts of Sarcocystis linearis and/or Sarcocystis taeniata (Basso et al, 2020).…”

“…In particular, it has long been postulated that red foxes and hunting dogs may play the final host role in the life cycle of Sarcocystis species affecting cervids, but for several species the exact final hosts are still unknown or are only suspected (Basso et al, 2020). In this context, based on molecular results and less consistent (98.8-99.1%) sequence identities, it was suggested that domestic dogs may be the final hosts of Sarcocystis linearis and/or Sarcocystis taeniata (Basso et al, 2020). Similarly, while tissue cysts of a Sarcocystis species with band-like protrusions were reported to be infective for the dog during experimental feeding (Poli et al, 1988), later the relevant species could not be identified with certainty (Gjerde et al, 2017b).…”

The Role of Birds of the Family Corvidae in Transmitting Sarcocystis Protozoan Parasites

“…Other authors have applied methods apart from species-specific PCR, such as cloning, and metabarcoding, to detect Sarcocystis spp. from samples containing oocysts or sporocysts [ 60 , 61 , 62 , 63 ]. However, previously conducted studies were also limited and revealed only a partial diversity of Sarcocystis spp.…”