Location: Egg and Poultry Production Safety Research Unit
Project Number: 6040-32000-012-015-S
Project Type: Non-Assistance Cooperative Agreement
Start Date: Aug 13, 2025
End Date: Aug 12, 2029
Objective:
Research conducted as part of this increase will be coordinated with the Cooperator as part of the project “Reduction of Foodborne Pathogens and Antimicrobial Resistance in Poultry Production Environments”. Recently, increased demand for antibiotic-free, “natural” products has pushed consumers towards the organic food market. This has impacted the poultry industry, where broiler meat harvested from alternative poultry farming production facilities, such as organic, free range and pastured, have increased in demand. The microbial safety of conventionally-raised poultry and their products throughout the entire farm-to-fork continuum has been studied in the US, but organic/pastured production studies related to food safety issues are limited, especially when focusing on the pre-harvest environments. Organic poultry farms are characterized by farms that rear birds without the use of antibiotics and allow the birds access to the outside, while pastured poultry operations require moveable pens/housing that are moved daily to fresh pasture. In our previous project plan we forged relationships with several pastured poultry operations. They have allowed us frequent and consistent access to their farms and flocks upon request, and openly discuss their management practices and allow collation of a wide variety of information, such as the presence of mixed species on-farm, vaccination protocols, feeding and rearing practices, and other management factors. Initial findings for our large-scale (41 flocks from 11 farms) study demonstrated that farm environment significantly impacted poultry-related microbiomes and pathogens, as do farm management practices such as feed composition. Additionally, meteorological variables, such as minimum average temperature and maximum wind speed and farm management practices, such as feed composition during brood and chlorination of water sources, were predictive of the presence of Listeria within the pre-harvest environment. Based on these findings, the proposed work will rear broilers in outdoor pastured poultry coops to study the effects of specific environmental/management variables on pre-harvest foodborne pathogen (Salmonella, Campylobacter, E. coli, and Listeria) prevalence in comparison to broiler flocks reared within conventional-style indoor pens, as well as comparing the effects of these different rearing systems on animal welfare, performance, processing microbial quality/safety, and meat quality.
Approach:
All field studies will be performed under the Cooperator's IAUCU and will be reared using the American Pastured Poultry Producers Association (APPPA) guidelines (https://apppa.org/Pastured-Poultry-Management-Practices). Broiler chicks bred to for pastured systems will be purchased and brooded in brooding pens to 21 days of age where they will be provided with fresh wood shaving and given food and water ad libitum. Chicks will be divided into 8 separate brooders each with 125 chicks, representative of the 4 flocks to be reared outdoors and the 4 flocks to be reared indoors. After brood, the 4 outdoor flocks will be moved to the 4 pastured broiler coops with solar-powered feeding and watering systems, while the 4 indoor flocks will be moved to separate indoor pens. All flocks will be reared in their respective environments until 56 days of age. During growout (21-56 days of age), the outdoor coops will be moved every day to provide fresh pasture daily, and both the indoor and outdoor flocks will be provided food and water ad libitum. At the end of the rearing period, all flocks will be processed at the UGA processing facility under the direction of the cooperators.
THroughout the studies, broiler management, including but not limited to animal welfare, gut microbiology/food safety, management/performance, will be studied. To assess the effect of these environmental/management variables on poultry gut microbiomes and foodborne pathogen prevalence, fecal and gastrointestinal tract samples will be collected on a weekly basis starting on the first day of age and traditional cultural and molecular microbiological techniques will be used. On a weekly basis, farm managers will collect feed consumption data and the cooperators will determine mean body weight and approximate feed conversion rate (FCR). The assess the effect of environmental/management variables on broiler welfare and behavior, lameness assessment will be conducted along with recording of foot pad and feather damage as birds interact under both rearing systems. Birds will also be assessed for signs of aggression. Animal welfare parameters will be recorded using implantable telemetry loggers. At processing, post-processing whole carcass rinses from the flocks will analyzed, and meat quality and myopathy assessments will be performed.