This report is on infestation with Chorioptes bovis of Holstein cattle on a dairy farm included 900 cows
in Tabriz. Ten heifers and 25 milking cows under the age of 5 years were infested. Clinical signs consisted of
alopecia, crusts, ulcerations and superficial skin fissures. Pruritus and itching were severe in all cases.
Lesions were present around the base of the tail, on the neck and below the knee. Skin scrapings were
examined and eggs, larvae, nymphs and adult mites were recovered. The infested animals were separated
from others and treated three times at weekly intervals with 0.05% solution of sebacil. Signs of improvement
were observed after the final treatment.