Figure 4.

Phylogenetic trees for NA gene. Phylogenetic trees were constructed by using the Bayesian, Markov Chain Monto Carlo approach as implemented in Mr Bayes. Coding region of all genes was used for analysis. The lengths of the horizontal lines are proportional to the number of nucleotide differences per site. Scale bar indicates number of nucleotide substitutions per site. Gs/Guangdong/1/96 was used as out group sequence. Abbreviations: BHGs – Bar headed goose, Ck – Chicken, Dk – Duck, Gs – Goose, Ws – Whooper swan, Md – Mallard, Tk – Turkey, Co – Cygnus olor, Gf – Guinea fowl, Pg – Peregrine, PgFc – Peregrine falcon,