Serological response of cattle to Brucella allergen after repeated intradermal applications of this allergen

The use of skin delayed‐type hypersensitivity as an adjunct test to diagnose brucellosis in cattle: A review

“…Likewise, naive cattle did not have an increase in skinfold thickness >2 mm after repeated injection of 0.1 ml brucellin. Furthermore, naive cattle that were tested with the SDTH test three, four, or five times every three weeks all tested seronegative for brucellosis (71), even though some cattle serologically reacted now and then either with the SAT or CFT. Such a response has no effect on the sero-diagnosis of brucellosis, as the results are not indicative of brucellosis and last less than a week.…”

“…It seems that an increase in skinfold thickness >2 mm at the injection site of brucellin may be used as guideline to indicate brucellosis in infected cattle (71). When this cut-off value was applied to naive cattle, none showed a skin reaction 22 mm following several brucellin injections (20).…”