Isolates ofSalmonella entericaEnteritidis PT4 with enhanced heat and acid tolerance are more virulent in mice and more invasive in chickens

Abstract

Summary: Two Enteritidis PT4 isolates which differed in inherent tolerance to heat, acid, H₂O₂and the ability to survive on surfaces were used to infect mice, day-old chicks or laying hens. The acid-, heat-, H₂O₂- and surface-tolerant isolate was more virulent in mice and more invasive in laying hens, particularly in reproductive tissue. However, no significant differences were observed in behaviour in chicks. Both PT4 isolates were able to infect chicks housed in the same room as infected birds, although the heat-tolerant isolate survived significantly better than the heat-sensitive one in aerosols.