Encounter the poultry red mite resistance to acaricides in Czechoslovak poultry-farming.

Poultry red mite susceptibility to permethrin, deltamethrin, tetramethrin, trichlorfon, fenitrothion, carbaryl and DDT, respectively, was screened within the territory of Bohemia by a method of diagnostic doses. The survey indicated widely spread resistance to DDT; in a few cases ineffectivity of permethrin, tetramethrin and trichlorfon, respectively, was also documented.