Abstract
Extract
Infectious bovine rhinotracheitis (IBR) was first recognized as a clinical entity in the U.S.A. in 1950 (Miller, Citation1955) and by 1954 had reached a high incidence in dairyherds and feedlot cattle (CitationSchroeder and Moys, 1954; CitationMcKercher et al., 1954, Citation1956). Subsequently CitationMadin et al. (1956) isolated the causal virus from nasal scrapings of clinically affected cattle, and this isolate was later identified by CitationArmstroag et al. (1961) as being of the herpesvirus group.