Susceptibility of avian hosts to experimental Gymnophalloides seoi infection

To determine whether avian species are susceptible to infection with Gymnop halloides seoi (a human-infecting intestinal trematode), we exposed 7 speci es of birds with metacercariae obtained from oysters. The birds were necrop sied at days 2, 4, and 6 postinfection (PI). The highest worm recovery at d ay 6 PI was obtained from the Kentish plover (Charadrius alexandrinus: (x) over bar = 56.0%). followed by the Mongolian plover (C. mongolus: 49.3%), a nd the grey plover (Pluvialis squatarola: 32.3%). In contrast, no mature wo rms were recovered from the great knot (Calidris tenuirostris). dunlin (C. alpina). black-tailed gull (Larus crassirostris). and mallard (Anas platyrh ynchos). Among the plovers, the worms attained the greatest size at day 6 P I (254.1 x 190.4 mum) in the Kentish plover. with a significantly higher nu mber of eggs in the uterus. The 3 species of plovers are highly susceptible to experimental G. seoi infection, suggesting that they could play a role as definitive hosts for these worms in nature.