Animals and birds, (people too!) are born with digestive tracts free of both pathogenic and beneficial bacteria. Colonization of the tract depends on the bacteria, the environment, diet and the animal. In the normal, healthy animal, a balance of microorganisms helps in the efficient digestion and absorption of nutrients and increases the body’s resistance to infectious diseases. During periods of stress, this balance can be altered. There is constant competition in the gut between disease causing bacteria and desirable bacteria. Unfortunately, E. coli, a disease causing bacteria, can double its population every fifteen minutes during ideal conditions while the desirable Lactobacillus requires twenty minutes.