Sarcocystis in the birds family Corvidae with description of Sarcocystis cornixi sp. nov. from the hooded crow (Corvus cornix)

Abstract

Having studied 67 birds of six species of the family Corvidae, Sarcocystis cysts were found in 16 (23.9%) individuals belonging to three species. The highest prevalence of infection (35.9%) was determined in the hooded crow (Corvus cornix). Two types of sarcocysts, which were temporarily called cysts type I and type V, were determined in the corvids examined. By light microscope, type I cyst wall seemed to be thin (< 1.0 microm) and smooth. Banana shaped cystozoites measured 6.0-8.0 microm in length. By light microscope, type V cyst wall seemed striated and reached up to 2.5 microm. Banana shaped cystozoites measured 6.1-7.9 x 1.4-1.8 microm. Ultrastructurally, the cyst wall amounted to 2.1 microm and had stump-like protrusions that differed greatly in size and shape. The parasitophorous vacuolar membrane had indentations and clearly visible (up to 0.2 microm in length) microprojections, which also differed considerably in size and shape. The ultrastructure of type V cyst wall differed from all those Sarcocystis spp. described thus far. On the basis of this-Sarcocystis cornixi sp. nov.-is proposed for this type of sarcocysts. Partial sequences of 18S rRNA and 28S rRNA genes were determined for this species and a phylogenetic analysis of the Sarcocystidae family was performed. In the phylogenetic tree, S. cornixi is grouped together with Frenkelia microti, F. glareoli, S. muris, S. neurona and the unnamed Sarcocystis species whose intermediate hosts are birds. S. cornixi is the most closely related to Sarcocystis sp. (cyst type I) from the white-fronted geese.

Sarcocystis calchasi sp. nov. of the domestic pigeon (Columba livia f. domestica) and the Northern goshawk (Accipiter gentilis): light and electron microscopical characteristics

“…Interestingly, cysts found in the whitefronted goose also exhibited a thin and smooth cell wall but conversely had banana-shaped cystozoites (Table 1; Butkauskas et al 2007). Aside from this, the cyst wall of the Sarcocystis species found in the hooded crow exhibited stump-like protrusions (Kutkiene et al 2008). Finally, the sporocysts of the Sarcocystis species derived from the intestine of a Cooper's Hawk as well as sporocysts from six other Cooper's Hawks described in the same study differed considerably in their size when compared with the species reported in the present study (Yabsley et al 2009).…”

“…Only 51% ITS 1 nucleotide sequence similarity with S. falcatula was determined. Instead, a phylogenetic comparison revealed close sequence homologies with Sarcocystis cysts found in the striated muscle tissue of a white-fronted goose (Anser albifrons), a hooded crow (Corvus cornix) and Sarcocystis sporocysts found in the intestine of a Cooper's hawk (Accipiter cooperi; Butkauskas et al 2007;Kutkiene et al 2008;Yabsley et al 2009). …”

Corvid birds (Corvidae) act as definitive hosts for Sarcocystis ovalis in moose (Alces alces)

“…Previously, such birds have only been known as intermediate hosts for members of this genus (Černá 1984;Kutkienė et al 2009). Erber et al (1978) fed two rooks (Corvus frugilegus) muscle tissues of roe deer containing sarcocysts but observed no sporocyst shedding.…”

The mallard duck (Anas platyrhynchos) as intermediate host for Sarcocystis wobeseri sp. nov. from the barnacle goose (Branta leucopsis)

“…In this study, reliable evolutionary relationships were revealed using entire 18S rRNA gene and partial 28S rRNA gene sequences. The concatenated 18S rRNA and 28S rRNA genes analysis have been successfully used in several studies within Sarcocystidae (Šlapeta et al 2003;Kutkienė et al 2009). The ITS-1 region is useful for closely related Sarcocystis species (Marsh et al 1999;Dubey et al 2006).…”

“…In recent years, DNA markers, mainly rRNA genes, have appeared to be able to overcome such complexity. Besides, the DNA analysis combined with the morphological one was successfully used to describe the new Sarcocystis species Dahlgren and Gjerde 2008a;Dahlgren and Gjerde 2008b;Kutkienė et al 2009). …”