Submitted to: Poultry Science Association Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: March 1, 2014
Publication Date: July 14, 2014
Citation: Gast, R.K., Guraya, R., Jones, D.R., Anderson, K.E. 2014. Horizontal transmission of Salmonella Enteritidis in experimentally infected laying hens housed in conventional or enriched cages. Poultry Science Association Meeting Abstract. 93(1):263. Technical Abstract: The majority of human illnesses caused by Salmonella Enteritidis are attributed to contaminated eggs, and the prevalence of this pathogen in commercial laying flocks has been identified as a leading epidemiologic risk factor. Flock housing and management systems can affect opportunities for the introduction, transmission, and persistence of food-borne pathogens in poultry. The animal welfare implications of different types of housing for laying hens have been widely discussed in recent years, but the food safety consequences of these production systems remain incompletely understood. The present study assessed the effects of two different housing systems (conventional cages and colony cages enriched with perching and nesting areas) on the horizontal transmission of S. Enteritidis among groups of experimentally infected laying hens. In each of two trials, 136 hens were distributed among cages of both housing systems and approximately 1/3 of the hens in each cage were orally inoculated with doses of 108 cfu of S. Enteritidis (phage type 13a in one trial and phage type 4 in the other). At regular intervals through 23 d post-inoculation, cloacal swabs were collected from all hens (inoculated and uninoculated) and cultured for S. Enteritidis. Horizontal contact transmission of infection was observed for both S. Enteritidis strains, reaching peak prevalence values of 27.1% of uninoculated hens in conventional cages and 22.7% in enriched cages. However, no significant differences (P > 0.05) in the overall frequencies of horizontal S. Enteritidis transmission were evident between the two types of housing. These results suggest that opportunities for S. Enteritidis infection to spread horizontally throughout laying flocks may be similar in conventional and enriched cage-based production systems.