Detection of Salmonella enterica Serovar Rissen in Slaughter Pigs in Northern Ireland

Salmonella enterica serovar Rissen has been recognised as a common serovarin humans and pigs around the world. This study investigated S. Rissenprevalence in pigs slaughtered in Northern Ireland additionally looking at antibioticsusceptibility profiles, genetic profiles and plasmid profiles to provideinformation on an emerging non-typhoid Salmonella serotype with the potentialto cause disease in humans. S. Rissen were isolated on five separate samplingoccasions from both the boning hall and slaughter line of a randomlyselected single pig abattoir in Northern Ireland (NI). Following antibioticsusceptibility testing against 16 antibiotics, all S. Rissen isolates were identifiedas susceptible to 15 antibiotics but resistant to tetracycline (R-type: Te).Of the 29 S. Rissen, 27 were isolated from pigs originating in NI and two S.Rissen were isolated from pigs originating in the Republic of Ireland (RoI).The combined results of the PFGE and plasmid profiling analyses were capableof subdividing the S. Rissen isolates into three distinct groups. The datasuggests that S. Rissen is an emerging serovar in Northern Ireland and continuedsurveillance of this serovar is warranted as it has the potential to causedisease in humans.