Dj. Forrester et al., Blood parasites of the ring-necked duck (Aythya collaris) on its winteringrange in Florida, USA, COMP PARASI, 68(2), 2001, pp. 173-176
Five species of parasites were found in blood smears from 283 ring-necked d
ucks, Aythya collaris (Donovan, 1809) overwintering in Florida. These inclu
ded the following (with overall prevalences in parentheses): Haemoproteus n
ettionis (Johnson and Cleland, 1909) (5.3%), Leucocytozoon simondi Mathis a
nd Leger. 1910 (9.2%), Splendidofilaria fallisensis (Anderson, 1954) (39.2%
), and 2 unidentified species of filaroids, Species I (6.0%), and Species I
I (13.8%). Ninety-seven ducks were infected with 1 species only, 43 with 2
species, and 8 with 3 species. The most common combined infection was L. si
mondi and S. fallisensis, which occurred 15 times. Prevalences of H. nettio
nis were significantly higher in ducks from the state's panhandle (far nort
hwest) and north-central regions, whereas prevalences of L. simondi were hi
gher in the panhandle. Microfilariae of unidentified Species II were more p
revalent in the north-central and southern regions. Microfilariae of S. fal
lisensis and the 2 unidentified species were more prevalent in female ducks
than in mates. Leucocytozoon simondi was more prevalent in juvenile ducks
than in adults, whereas the prevalences of the microfilariae of both uniden
tified species were higher in adult ducks.