Project Number: 6040-32420-003-006-S
Project Type: Non-Assistance Cooperative Agreement
Start Date: Sep 1, 2021
End Date: Aug 31, 2026
The rapid transition to cage-free laying hen housing has occurred ahead of the science to determine the best practices for rearing and managing laying hens for extensive housing systems. The overall objectives of the project are: 1. Determine the transmission and persistence of pathogens in pullets reared under various housing practices. 2. Ascertain the impact of laying hen flock management strategies on the vertical and horizontal transmission of pathogens.
Commercial genetic lines of laying hens will be reared under commercial pullet rearing programs in cage-free housing systems. The hens will then be challenged with Salmonella spp. in an animal Biosafety Level 2 cage-free production facility. Various studies will be conducted to determine the impact of cage-free rearing conditions on horizontal transmission within the flock, organ invasion, and vertical transmission of the challenge organism into eggs laid by the hens. The specific rearing criteria will include: stocking density, hen age at housing in the laying facility, rear-in-place, and potentially other cage-free pullet management strategies under consideration by the egg industry over the course of the agreement. Salmonella Enteritidis and other Salmonella species will be the challenge organisms but may be changed if other organisms becomes a concern in the U.S. egg supply over the course of the agreement.