Feathers of infested birds are discolored by mite excrement and eggs, and the skin is scabby. Control of the northern fowl mite must be directed to the birds. Chicken mites and northern fowl mites suck blood, resulting in emaciation and lowered egg production. Continued heavy infestations can kill the birds. Scaly-leg mites burrow under the skin, especially on the lower legs and feet.
Legs become scaly, swollen, and exude lymph fluid.
Severely infested birds may be crippled or unable to walk. In addition to treating with insecticides, legs may be dipped in a mixture of two parts raw linseed oil and kerosene. Control mites by treating their hiding places. Treat roosts, walls, litter, and equipment by painting, spraying, or dusting. Treat all cracks, crevices, and rough spots.