Highlights • We model Salmonella transmission around varying structures of pig farm within the UK. • We formulate and analyse the basic reproduction number for this system. • Identify the shedding rate to be of particular importance in Salmonella spread. • Highlight differences in Salmonella dynamics between differing farm structures. A multi-group semi-stochastic model is formulated to describe Salmonella dynamics on a pig herd within the UK and assess whether farm structure has any effect on the dynamics. The models include both direct transmission and indirect (via free-living infectious units in the environment and airborne infection). The basic reproduction number R 0 is also investigated. The models estimate approximately 24.6% and 25.4% of pigs at slaughter weight will be infected with Salmonella within a slatted-floored and solid-floored unit respectively, which corresponds to values found in previous abattoir and farm studies, suggesting that the model has reasonable validity. Analysis of the models identified the shedding rate to be of particular importance in the control of Salmonella spread, a finding also evident in an increase in the R 0 value.
【저자키워드】 basic reproduction number, Salmonella, R0, Semi-stochastic model,