Complete genome sequence of bovine herpesvirus type 1.1 (BoHV-1.1) Los Angeles (LA) strain and its genotypic relationship to BoHV-1.1 Cooper and more recently isolated wild-type field strains.

The Cooper and Los Angeles (LA) strains were the two original respiratory strains of bovine herpesvirus type 1.1 (BoHV-1.1) isolated in the 1950s from cattle with infectious bovine rhinotracheitis. We report the complete genome sequence for the BoHV-1.1 LA strain and compare it to the prototype Cooper strain and six wild-type BoHV-1.1 isolates. A nucleotide sequence divergence of 0.74% was noted across the two complete genomes, caused by 19 single-nucleotide polymorphisms (SNPs) involving 12 genes and insertions/deletions that primarily affected the number of repeats within reiterated repeat regions of the genome. Phylogenetic analysis revealed that Cooper and LA strains are genetically the most ancient strains from which all of the more-recently isolated field strains of BoHV-1.1 evolved.