What Occurs When The Right Bacteria

Are Not Present


When I ran the pathogen-free rodent colonies at the National Institutes Of Health, one of my assignments was to develop a germ-free guinea pig colony. That meant delivering all the g. pigs by cesarean section and maintaining them with absolutely no bacteria in sterile rooms. Guinea pigs that live in these conditions never are normal – but because there are no bad bacteria in their environment, they do survive.

The first thing that became apparent was that food did not move through these animals intestines in a normal manner. Somehow, the good bacteria were required for the stomach, intestines and cecum to have normal , rhythmic contractions. The second thing that became apparent was that the ridges projections (papilla) that normally line the intestines and cecum never developed to their full length. These papilla are involved in absorption of nutrients and contain the first-line defenders of the body’s immune system. Consequently, the level of antibodies in their blood stayed low. The third striking change was in the size and thickness of the cecum. In germ free guinea pigs – as in rabbits - the cecum became over 3 times it normal size. Many of these animals died suddenly of a condition called cecal volvulus. I tried to give you an idea of what happens in a drawing - which you might find gross.

We could minimize this problem by giving the guinea pigs an oral brew of bacteria. We called it the " schaedler cocktail " similar to one used in rodents and by feeding diets that were high in forage cellulose and ground more coarsely. A similar effect happens is seen in rabbits. and seems to be linked to the volatile fatty acids produced by these bacteria.