Farm specific risk factors for Campylobacter colonisation in Danish and Norwegian broilers

Area of Science:

• Veterinary Epidemiology
• Food Safety
• Bacterial Zoonoses

Background:

• Campylobacteriosis is the primary bacterial zoonotic disease in the European Union, with broiler chickens identified as a major source of human infection.
• Understanding risk factors for Campylobacter colonization in broiler flocks is essential for developing targeted interventions to reduce human exposure.

Purpose of the Study:

• To identify and compare risk factors associated with Campylobacter colonization in Danish and Norwegian broiler flocks.
• To evaluate the benefits of a bi-national dataset for identifying significant risk factors.

Main Methods:

• A bi-national risk factor survey was conducted on over 5200 Danish and Norwegian indoor, conventional broiler flocks.
• Data from a standardized questionnaire with over 40 explanatory variables from 277 farms were analyzed using generalized linear models with stepwise selection.
• Models were explored using single-country datasets and combined bi-national data.

Main Results:

• Norwegian broiler flocks exhibited a lower risk of Campylobacter colonization compared to Danish flocks.
• Common risk factors included older broiler houses (>5 years), longer downtime between flocks, lack of a separate ante-room/barrier, and specific drinker nipple types.
• Country-specific risk factors were identified, such as farm size and water source in Norway, and boot dips and stocking density in Denmark.

Conclusions:

• Combining Danish and Norwegian data in a bi-national model enhanced statistical power and identified more risk factors than country-specific models.
• Farm management practices, housing characteristics, and water sources are significant determinants of Campylobacter colonization in broiler flocks.
• The findings provide a foundation for implementing effective, evidence-based biosecurity measures to control Campylobacter in poultry production.