Mice as carriers of Salmonella enteritidis on persistently infected poultry units

Abstract

Evidence of the possible role of wild mice in the epidemiology of Salmonella enteritidis infection on broiler breeder and layer breeder units was obtained by a bacteriological examination of local mice. Persistent S enteritidis infection in birds on these units had been a problem and a high proportion of the mice were found to carry salmonella. S enteritidis was isolated from the liver and the intestine of most of the mice, indicating a systemic infection. Three-week-old chicks were infected by contact with droppings from mice which had been infected experimentally with S enteritidis two and five months previously. Wild mice infected artificially or naturally excreted S enteritidis intermittently, with up to 10(4) organisms in some individual droppings. A naturally infected mouse which died after intermittently excreting small numbers of S enteritidis in its droppings for 19 weeks had 10(4) organisms/g of liver and 10(3)/g of macerated intestine and contents. S enteritidis was also found in fetal tissue in a naturally infected mouse suggesting the possibility that the organism might be transmitted vertically.

Salmonella enterica serovar Enteritidis: a Mini-review of Contamination Routes and Limitations to Effective Control

“…There is evidence that S. Enteritidis spreads rapidly from infected day old chicks to pen mates reared on litter 78,81 . Poultry may also get infected from feed 43,66 , water 36 , rodents 4,17,40 , or by contact with other poults or chicks. Infection by these routes in chicks reached 100% within seven days of contact 81 .…”

The Global Regulator ArcA Controls Resistance to Reactive Nitrogen and Oxygen Intermediates in Salmonella enterica Serovar Enteritidis

“…Most of the cases were associated with consumption of contaminated eggs laid by infected chickens (6,33,38). Chickens are probably infected on poultry farms by field mice, which serve as a reservoir for S. enterica serovar Enteritidis (10,23,25). Therefore, infection of mice is believed to be a link in the natural transmission cycle of S. enterica serovar Enteritidis.…”

Salmonella enterica Serovar Enteritidis (SE) Infection in Chickens and Its Public-Health-Risk Control Using an SE Vaccine in Layer Flocks

“…Mode of SE infection in chickens and chicken flocks) was referred to and investigated as a model in the SE vaccine development. However, a recent study and our survey results suggested that SE contamination/infection of chickens disseminates through mouse-mediated transmission between hen houses (Davies RH et al 1995, Henzler DJ et al 1992, and not by vertical infection as in PD infection model (Yamane Y et al 2000). Unlike SE infection of mice and humans (Guiney DG Bohez L et al 2007, and the infection is not systemic and manifests no symptoms in infected chickens.…”