Waterfowl mortality caused by Cyathocotyle bushiensis Khan, 1962 (Trematoda: Cyathocotylidae), St. Lawrence River, Quebec

Abstract

In St. Lawrence River marshes, fatal sporadic and epizootic typhlitis in breeding populations of black ducks, Anas rubripes; blue-winged teal, A. discors; and migrant green-winged teal, A. carolinensis, is attributed to Cyathocotyle bushiensis Khan, 1962. This is the first report of C. bushiensis in natural definitive hosts, and the first record of the genus Cyathocotyle in North America. Pathogenicity of C. bushiensis was confirmed experimentally by using metacercariae from the most abundant local gastropod, Bythinia tentaculata, to produce cyathocotyliasis in Pekin ducklings.

Spatio-temporal variation in prevalence and intensity of trematodes responsible for waterfowl die-offs in faucet snail-infested waterbodies of Minnesota, USA

“…rediae and sporocysts in snails in our study was lower, for example, than that reported for Upper Mississippi River (12.3–15.8%; Herrmann and Sorensen, 2009) and Golden Hill Creek in NY (12.3%, Karatayev et al., 2012). Prevalence of C. bushiensis rediae and sporocyst was also lower than reported for the Upper Mississippi River (2.1–2.2%) and more similar to those reported in Québec (0.5%; Gibson et al., 1972; 0.05%; Ménard and Scott, 1987b). This low level of sporocyst and rediae infection might indicate that the supply of eggs from infected waterfowl limits the life cycle of these parasite stages in the waterbodies we studied.…”

“…The lowest prevalence and intensity has been found pretty consistently in summer (Ménard and Scott, 1987b, Herrmann and Sorensen, 2009), and that was the most common pattern we observed as well. We suggest that the addition of new snails to the population outpaced the addition of new trematode infections in our study, where infections with sporocysts were uncommon like in Québec (Gibson et al., 1972, Ménard and Scott, 1987b). We suggest that in the impoundment lake of the Upper Mississippi River, where sporocyst and rediae infections are more prevalent (Herrmann and Sorensen, 2009), high waterfowl use increases the availability of trematode stages relative to snail abundance.…”

“…The faucet snail is the only known first intermediate host of these trematodes in the Midwestern United States and also serves as the second host for both C. bushiensis and Sphaeridiotrema spp. (Khan, 1962, Gibson et al., 1972, Huffman and Fried, 1983, Ménard, 1986, Lepitzki et al., 1994). Although other snail species have been shown to be susceptible to infection of Sphaeridiotrema spp.…”

Molecular phylogeny of the Cyathocotylidae (Digenea, Diplostomoidea) necessitates systematic changes and reveals a history of host and environment switches

“…No Cyathocotyle species is restricted to North America or was originally described from the continent; however, the European species C. bushiensis was reported from the Midwestern United States. Often, these reports were associated with massive die‐offs of waterfowl (Gibson et al, ; Herrmann & Sorensen, ; Hoeve & Scott, ). Surprisingly, no DNA sequences of this rather infamous species were available until now.…”

“…Unlike most other diplostomoideans, cyathocotylids usually have an undivided body, a cirrus‐sac enclosing a cirrus and a seminal vesicle and, sometimes, a small caudal appendix (Niewiadomska, ). Some members of this family are of economic and conservation concern; for instance, Cyathocotyle bushiensis Khan, has been associated with massive die‐offs of aquatic birds in the Midwestern United States (Gibson, Broughton, & Choquette, ; Herrmann & Sorensen, ; Hoeve & Scott, ). Mühling () initially established the subfamily Cyathocotyleae Mühling, for his newly described genus Cyathocotyle Mühling, with Cyathocotyle prussica Mühling, as the type‐species.…”