Delayed type hypersensitivity theilerin test in cattle vaccinated against Theileria annulata infection.

Theilerin was prepared and its total nitrogen was determined at level of 1 mg/ml. Seventy-two Holstein Friesian cattle recovered from acute theileriosis or vaccinated received 0.1 ml of theilerin intradermally at normal concentration of total nitrogen or other dilutions (1 / 10 and 1 / 100). Some 60(% of calves and 66.67% of milking cows receiving normal theilerin showed more than 1 mm increase in skin thickness at the site of inoculation (mean value of 1.86 mm for calves and 3.46 mm for milking cows). The pathological examination of the inoculation site showed infiltration of lymphocytes. No changes of general condition were observed in animals under study. The result indicated that the test is positive and could be used for checking Immunity in vaccinated animals.