INVASION OF CHICKEN REPRODUCTIVE TISSUES AND FORMING EGGS IS NOT UNIQUE TO SALMONELLA-ENTERITIDIS

Experiments were conducted in which Salmonella enteritidis Phage Type 8, Phage Type 2, and RDNC (reaction does not conform) or three isolate s of Salmonella typhimurium of diverse origin were fed to adult laying hens to determine if S. enteritidis has a selective advantage over S. typhimurium, which is now rarely isolated from chicken eggs, in its c apacity to invade reproductive tissues. The results revealed that S. e nteritidis and S. typhimurium may be equal in their potential to colon ize the tissues of the reproductive tract and eggs that are forming in the oviduct prior to oviposition. S. enteritidis, but not S. typhimur ium, was isolated from egg contents after oviposition. The degree to w hich intestinal, hepatic, splenic, or reproductive tissues were coloni zed by either serotype was not seen to affect the rate of colonization of eggs forming in the oviduct or the contamination of eggs after ovi position. Virulence factors related to the difference in the associati on of S. enteritidis and S. typhimurium with egg-borne salmonellosis r emain to be defined.