We expect our animals to eat well, convert feed efficiently and grow or produce rapidly. In the past 20 years growth rates have increased dramatically and feed conversion rates have fallen sharply as animals have been genetically selected and bred for performance. However, we have failed to consider the most important aspect of production and that is the intestine. Fast growth and concentrated feeds put enormous stress on the intestine, and when this organ is stressed, it may result in the occurrence of diseases. The concerns over salmonella, escherichia and campylobacter are the result of expecting the intestinal development to match that of the genetic selection processes.
When disease problems were first identified they were treated with antibiotics, then antibiotics were used to keep the diseases away until eventually the bacteria became resistant to the antibiotics. The world responded by banning antibiotics in animal feed too late and now we need an alternative.
In Figure 1 we can see high levels of antibiotic resistance in pigs and significant resistance in poultry but low levels in feed. This confirms that feed is not the source of infection. There are more bacterial cells in the intestine of a healthy animal than there are cells in the animal. It therefore means that you need a microbiological solution to keep the animals healthy.