PROBIOTICS, PREBIOTICS, AND SYNBIOTICS. WHAT ARE THEY AND WHEN SHOULD THEY BE IMPLEMENTED?

PROBIOTICS, PREBIOTICS, AND  SYNBIOTICS. WHAT ARE THEY AND WHEN SHOULD THEY BE IMPLEMENTED? 

Stanley L. Marks, BVSc, PhD, DACVIM (Internal Medicine, Oncology), DACVN University of California, 

Davis, School of Veterinary Medicine, Davis, CA, USA 

Professor of Small Animal Medicine 

The mammalian intestinal tract contains a complex, dynamic, and diverse population of non-pathogenic bacteria.  Researchers have estimated that the human body contains 10.000.000.000.000 cells, only 10% of which are not bacteria, and belong to the human body proper. 1. There has been a plethora of research focusing on the mechanisms by which pathogenic bacteria influence intestinal function and induce disease; however, recent attention has focused on the indigenous non-pathogenic microorganisms and the ways in which they may benefit the host.  Initial colonization of the sterile newborn intestine occurs with maternal vaginal and fecal bacterial flora.  The first colonizers have a high reduction potential and include species such as enterobacter, streptococcus, and staphylococcus. These bacteria metabolize oxygen, favouring the growth of anaerobic bacteria, including lactobacilli and bifdobacteria.  Colonization with these bacteria is significantly delayed in caesarean deliveries, 2. leading to delayed activation of the efferent limb of the mucosal immune response. 3.Additional beneficial effects of developing a normal bacterial flora is seen in germ free mice that have small intestines that weigh less than their healthy counterparts.  This effect occurs partly due to underdevelopment of lymphoid constituents, with a lack of plasma cells in the lamina propria and Peyer’s patches, and subsequent reduction in IgA production.  Exposure to bacteria results in a reversal of this phenomenon within 28 days of exposure.