According to Professor Bohach, Bifidobacterium needs to be replaced first, since it sets the stage for other species. Cultured milk foods, such as yogurt and buttermilk, contain this beneficial bacteria, as do supplements called probiotics. Many helpful species are on food and other surfaces, so a person may get them without even realizing it. Most are good bacteria pathogenic ones are actually rare in comparison to all the good bacteria around us. She says that many bacteria live in close contact with our bodies on hair, teeth, skin, and in the gastrointestinal tract.
Bacteria ARE smaller, however.
Salmonella , another bacteria that can cause problems for people, is present in chickens. To block Salmonella growth, caged chicks are often given probiotics made from the fecal material of adult chickens. Caged chicks need probiotics because they don t come in contact with adult s feces as uncaged chicks do. Even young termites get their gut flora from anal secretions of other termites, which they need to help them digest wood fiber. Regardless of how we get them, however, we are much healthier because of these helpful intestinal bacteria.