Ornithonyssus spp remain on chickens permanently. Dermanyssus mites parasitize chickens nocturnally. Heavy mite infestation is characterized by anemia and the appearance of black mite exoskeleton casts and excreta in the vicinity of the vent. Argasid ticks are nocturnal feeders and favor the soft unfeathered skin beneath the wings. Parasitized birds show multiple hematomas associated with feeding sites.
Ticks transmit spirochetosis.
Only approved insecticides should be applied to poultry or used in the vicinity of housing to avoid contamination of the food chain. Insecticides should be used in accordance with manufacturers' label instructions. The condition occurs infrequently in commercial flocks but may be diagnosed in backyard and village birds. The fungus is spread by direct contact or by contaminated cages or transport coops. 34.4 Clinical Signs Grey to white scaly lesions appear on the comb and wattles, spreading progressively, especially in young birds.