Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Phylogenic tree inferred from the S amino acid sequences of 110 LX4 genotype IBV strains and five reference strains. The trees were constructed using the neighbor-joining method and bootstrap values calculated from 1000 trees. The IBV strains used for comparison of amino acid similarities are in bold.
