Salmonella enterica is one of the leading causes of foodborne illness in the United States. An increasing number of Salmonella infections are resistant to antibiotics and many of the genes responsible for those resistances are carried by mobile genetic elements. Although the relationship between antibiotic resistance genes and mobile genetic elements is well established, the association between specific genes and specific mobile elements and specific genes with other genes remains unexplored. In order to investigate the association of antibiotic resistance genes with mobile genetic elements in S. enterica, whole genome sequences of diverse isolates were investigated. Additionally, isolates of S. Infantis containing the pESI plasmid were also investigated. The majority of antibiotic resistance genes were found to be associated with plasmid sequences. Antibiotic resistance genes were also found to be arranged in antibiotic resistance cassettes (ARCs). It was determined that pESI plasmid of S. Infantis contains a set of 101 core genes and plasmids isolated from U.S. food animals were found to be similar to those plasmids collected from U.S. humans and internationally, but two lineages of the plasmid are circulating.