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Nutrient Absorption in Gnotobiotic Animals

  • Géza G. Bruckner
  • Jozsef Szabó
Chapter
Part of the Advances in Nutritional Research book series (ASIB, volume 110)

Abstract

Animals, whatever the species, are constantly exposed to a fluctuating external population of microorganisms. These microorganisms constitute part of the host’s “external environment,” and if the delicate balance regulating their numbers is disrupted, or if they gain access to the host’s “internal environment,” they may be detrimental to the host’s homeostatic mechanisms. The interactions between the gastrointestinal (GI) microflora and the host animal were first recognized by Pasteur (1885) nearly a century ago. Pasteur postulated that the microflora were indispensable to the host and assumed that in the course of phylogenetic evolution, microbial associates developed that assisted in the “survival of the fittest” (Schottelius, 1902). Nencki (1886) and later Metchnikoff (1903) perceived the microflora as antagonistic to the host’s well-being. Some sixty years elapsed before definite proof of “reproducing germfree existence” was obtained by Gustafsson (1948) and Reyniers and co-workers (1946, 1949). With the establishment of the gnotobiotic (known flora) animal as a tool, it became possible to assess the total effect of the microflora on the host’s nutritional, physiological, biochemical, and morphological status, to study the relationship between individual species of microorganisms in mono-, di-, or polyassociation with the host, to study the homeostatic effects which microorganisms exert on each other directly or indirectly, and to determine the effect of the host on its microflora.

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Copyright information

© Springer Science+Business Media New York 1984

Authors and Affiliations

  • Géza G. Bruckner
    • 1
  • Jozsef Szabó
    • 2
  1. 1.Department of Clinical NutritionUniversity of Kentucky, Medical Center Annex TwoLexingtonUSA
  2. 2.Department of Animal HygieneUniversity of Veterinary ScienceBudapestHungary

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