Industrial farm animal production (IFAP) has become increasingly common throughout the world. Worldwide, industrial systems now account for approximately two-thirds of poultry meat production and half of egg and pig meat production, with developing countries already producing approximately half of the world’s industrial pork and poultry by 2006.
Inherent design and operational requirements of IFAP facilities can create biosecurity problems with both bioexclusion and biocontainment—efforts to prevent the respective influx and efflux of pathogens. These may help explain why large commercial flocks may be up to 10,000 times more likely to report outbreaks with pathogens such as highly pathogenic avian influenza H5N1 compared to small backyard flocks.
Humane Society International, "An HSI Fact Sheet: Biosecurity Challenges of Industrial Farm Animal Production" (2014). HSI Fact Sheets: Farm Animal Protection. Paper 3.