Introduction
Livestock farming, raising animals as a source of food for people, has undergone a substantial transformation over the past few decades. Production of cattle, hogs, and chickens has shifted from smaller, family-owned farms to large-scale industrial agricultural facilities often known as concentrated animal feeding operations (CAFOs). As part of that shift, cattle no longer graze on pastures, but instead eat grain. Their stomachs are not designed to handle such a diet and this has led to the emergence of E. coli O157:H7, a bacteria that has serious consequences for human health. Also of great importance to human health is the issue of antibiotic resistance. As cattle operations moved from smaller farms to CAFOs, animals became more crowded and more susceptible to disease. Therapeutic use of antibiotics led to the discovery that animals on constant low doses antibiotics grew larger faster. As farms continue to grow and antibiotic use increases, the emergence of resistant organisms must be addressed. A frequently unconsidered part of CAFOs is the enormous amount of waste produced. Management if the manure is a complex issue that has no easy answers and has the potential to contaminate the surrounding environment. Modern livestock production is hardly recognizable from what it was even 50 years ago and the issues and problems have grown along with it.
While modern agricultural methods may produce economical benefits for the supplier and consumer, the scale of foodborne transmission is an increasing public health concern, and new hazards are being recognized.
Learning Objectives
After successfully completing this module, students will be able to:
- Understand the biological consequences and threats to public health that result from livestock production in concentrated animal feeding operations (CAFOs).
- Learn the repercussions of feeding cattle grain instead of grass.
- Discuss the risk factors of large-scale use of antibiotics to speed cattle growth and production, and proposed regulations.
- Explain the processes by which bacteria become resistant to antibiotics.
- Discover how the density of cattle housing and disposal of manure can result in the contamination and spread of the most commonly recognized foodborne infections.
- Define Escherichia coli 0157:H7,, how is spread, and its public health impacts.
- Explain prevention methods that consumers can implement to protect themselves against foodborne illness.