Figure 2

Phylogenetic tree of Salmonella Enteritidis using single nucleotide polymorphic loci. A total of 1,360 SNPs was used to assess the genetic distances among eleven Canadian field isolates of Salmonella Enteritidis and were compared to the reference P125109 strain. The reference strain obtained in the United Kingdom (reference [18]) and an isolate from a clam obtained as part of Canada’s Shellfish sanitation program (SE 9) were the most divergent of all genomes studied. SE 2 and 3 were obtained from the same poultry hatchery on the same day and showed genetic closeness based on SNPs and PFGE data although the phage types were different (Table 3). SE 7, 10 and 11 were obtained from the same premises and also showed close genetic distances by SNPs, PFGE and phage typing. SE 4, 5 and 6 showed genetic closeness and had similar PFGE results but SE 6 had a distinct phage result from the other two isolates. All three isolates were from the same province in Canada but SE 6 was obtained from a poultry premise different from where SE 4 and 5 originated.