Cell-mediated immune response in cattle to bovine respiratory syncytial virus

Cattle inoculated with bovine respiratory syncytial virus (BRSV) were evaluated for the development of a cell-mediated immune response. Results of the leukocyte migration-inhibition test under agarose and the delayed hypersensitivity test indicated that a cell-mediated immune response was elicited after intranasal inoculation of calves with BRSV. Migration inhibition in the leukocyte migration-inhibition test was detected by postinoculation day (PID) 5 and reached maximum inhibition on PID 21. Inhibition of leukocyte migration was still evident by PID 42 when values were still appreciably greater than preinoculation values. All of the calves inoculated with BRSV developed a delayed hypersensitivity skin response when challenge exposed intradermally with BRSV antigen.