Salmonella enterica serovar Enteritidis is the leading cause of salmonellosis in people and modeling of infections in chickens is used to identify intervention strategies. Review of 80 manuscripts encompassing 119 experiments indicated that the mean dose of infection was 10exp8 CFU per bird. Experiments less than 10exp6 CFU were conducted mostly in immature birds. To address a lack of information on the impact of low dosages on the hen at lay, two experiments were conducted in triplicate. In Experiment A, hens were infected intramuscularly at 10exp3, 10exp5, and 10exp7 CFU. For Experiment B, hens were infected orally with 5 x 10exp3 CFU with 4 strains from different genomic clades. Samples cultured were liver, spleen, ovarian pedicle and paired ceca in both experiments. Eggshell microbiome taxa were assessed in Experiment B. Results indicated that dosages of 10exp3 CFU in both experiments produced enough positive samples to be used within models. The intramuscular route resulted in approximately twice as many positive samples as the oral route. The kinetics of infection appeared to differ between low and high dosages suggestive of a J-curve response. These results could impact risk assessments if the hen at lay has a non-linear response to infectious dose.

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