Parenteral infections of coots, Fulica americana (Gm.), with Cyclocoelum mutabile (Zeder, 1800) and Cyclocoelum oculeum (Kossack, 1911) (Cyclocoelidae)

Abstract

Newly excysted Cyclocoelum mutabile and Cyclocoelum oculeum were injected into coots, Fulica americana. Six of the eight coots injected intraperitoneally with C. mutabile became infected. Two coots, necropsied 6 days postinfection (pi), had young C. mutabile in the liver. Four of the remaining six coots necropsied 45 days pi had adult C. mutabile in the air sacs, and all infected coots exhibited evidence of fluke migration in the liver. Five of 10 coots injected intraperitoneally with C. oculeum became infected. Two of four coots necropsied 6 days pi were infected and young C. oculeum were recovered from the body cavity. Three of the remaining six coots were found to be infected at necropsy 45 days pi and specimens of C. oculeum were recovered from the air sacs and nasal sinuses. Three of six coots receiving newly excysted C. oculeum injected directly into the interclavicular air sac harboured flukes in the air sac, trachea, and nasal sinuses at necropsy 45 days pi. In both experiments involving C. oculeum, specimens recovered from the nasal sinus were gravid, or nearly so, whereas those found in the air sacs and trachea were smaller and less mature. No evidence of liver migration in either experiment involving C. oculeum was observed.