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ARS Home » Southeast Area » Athens, Georgia » U.S. National Poultry Research Center » Egg and Poultry Production Safety Research Unit » Research » Publications at this Location » Publication #404440
Research Project: Reduction of Foodborne Pathogens and Antimicrobial Resistance in Poultry Production Environments

Location: Egg and Poultry Production Safety Research Unit

Title: Internal organ colonization by Salmonella Enteritidis in layer pullets infected at two different ages during rearing in cage-free housing

Author
item Gast, Richard
item Jones, Deana
item Guraya, Rupinder - Rupa
item Garcia, Javier
item KARCHER, DARRIN - Purdue University

Submitted to: Poultry Science Association Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 4/20/2023
Publication Date: 9/12/2023
Citation: Gast, R.K., Jones, D.R., Guraya, R., Garcia, J.S., Karcher, D.M. 2023. Internal organ colonization by Salmonella Enteritidis in layer pullets infected at two different ages during rearing in cage-free housing. Poultry Science Association Meeting Abstract. 102 (E.Suppl.1):135.

Interpretive Summary:

Technical Abstract: The poultry housing environment plays a significant role in the transmission and persistence of the egg-associated pathogen Salmonella Enteritidis in laying flocks. The commercial egg industry is in the midst of a transition toward cage-free housing, but the food safety ramifications of this shift are not yet certain. The present study assessed internal organ colonization by S. Enteritidis in layer pullets reared in cage-free housing and infected at two different ages. Groups of 280 pullets were transferred from the rearing facility (at 9 wk of age in one trial and 15 wk in another) to a containment facility with 4 isolation rooms simulating commercial cage-free barns with perches and nest boxes (70 birds/room). 24 pullets in each room were orally inoculated with S. Enteritidis immediately after placement in the containment facility. At 1-2 wk post-inoculation in each trial, samples of liver, spleen, and intestinal tract were collected from all birds in 2 rooms for bacteriologic culturing to detect S. Enteritidis. At 21-22 wk of age, samples of spleen, ovary, and intestinal tract were similarly collected and tested from all birds in the remaining 2 rooms. Among samples collected at 1-2 wk post-inoculation, S. Enteritidis was isolated significantly more often (P < 0.05 in Fisher’s Exact Test) from groups of pullets infected initially at 15 wk of age than from those infected at 9 wk (61% vs. 38% of livers, 59% vs. 31% of spleens, and 84% vs. 57% of intestines). Among samples collected at 21-22 wk of age, the frequency of recovery of S. Enteritidis was again significantly greater in birds infected at 15 wk of age than in those infected at 9 wk (16% vs. 6% of spleen, 9% vs. 1% of ovaries, and 26% vs. 10% of intestines). These data suggest that S. Enteritidis infections introduced into flocks during the later stages of pullet rearing have greater potential to persist into the early phase of egg production.