Beneficial Bacteria Boost Intestinal Health

The studies were led by microbiologist Gloria Solano-Aguilar with the ARS Nutrient Requirements and Functions Laboratory, one of seven research units at the Beltsville (Md.) Human Nutrition Research Center. Solano-Aguilar received funding from Nestlé Nutrition of Glendale, Calif.

Healthy animals and humans benefit every day from trillions of natural intestinal bacteria. These friendly bacteria help keep "bad" bacteria from gaining a foothold that could lead to illness or disease. In the first study, the common probiotic strain Bb 12 was fed to three pregnant sows, while a placebo treatment was fed to three pregnant control sows. The scientists then fed the same Bb 12 treatment to half of each sow's litters, resulting in four experimental groups.

Solano-Aguilar studied gene expression patterns in tissue taken from each animal's lymph nodes, liver, spleen and intestine. She also studied the animals' intestinal contents. The team then compared the gene expression patterns in the pigs from all four groups. The probiotic was found to induce innate immune activity in the colon where the probiotic was in highest concentration.

In a separate study, half of a group of test pigs were treated with the Bb 12 probiotic before all of the test pigs were exposed to a worm infection. The researchers then compared the response to infection of the group of pigs that received the probiotic treatment with the response of those that did not receive the treatment. Preliminary results show better response to the infection--and improved nutrient absorption--in the group of pigs that were supplemented with the probiotic treatment prior to the infection.

ARS is the U.S. Department of Agriculture's chief scientific research agency.