Browsing by Subject "microbiota"

Now showing 1 - 3 of 3
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    Effects of dietary fiber on swine intestinal epithelial and immune response
    (2017-05) Ferrandis Vila, Marta
    In order to reduce feed costs, the use of high-fiber ingredients such as corn dried distiller’s grains with solubles and wheat middlings has become a common practice among swine farmers. However, caloric efficiency and growth of pigs fed high-fiber feed ingredients is usually less than pigs fed corn-soybean meal diets. Supplementation of pigs fed high-fiber diets with fiber-degrading enzymes is an approach to increase energy and amino acid digestibility that may result in a more cost-effective production method. Different components of fiber will modify the intestinal microbiome and epithelial parameters such as mucin expression, likely leading to changes in the intestinal immune response. Therefore, the focus of this thesis is to identify the cytokine profile in the swine intestine caused by fiber sources and fiber-degrading enzymes, and to define whether fiber actions on the intestinal epithelium are mediated through the activation of a localized immune response.
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    Gut microbiome westernization in Hmong and Karen refugees and immigrants in the United States
    (2018-08) VANGAY, PAJAU
    Many United States immigrant populations develop metabolic diseases post-immigration, but the causes are not well understood. Although the microbiome plays a role in metabolic disease, there have been no studies measuring the effects of U.S. immigration on the gut microbiome. We collected stool, dietary recalls, and anthropometrics from 514 Hmong and Karen individuals living in Thailand and the U.S., including first- and second-generation immigrants and 19 Karen individuals sampled before and after immigration, as well as from 36 U.S.-born Caucasian individuals. Using 16S and deep shotgun metagenomic DNA sequencing, we found that migration from a non-Western country to the U.S. is associated with immediate loss of gut microbiome diversity and function, with U.S.-associated strains and functions displacing native strains and functions. These effects increase with duration of U.S. residence, and are compounded by obesity and across generations.
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    How Prenatal Maternal Stress Predisposes Offspring Toward Development of Gastrointestinal Disorders
    (2023-04-20) Boehmer, Abigail
    Prenatal maternal stress is highly prevalent in different circumstances, whether it’s depression, anxiety, an adverse major life event, or a difficult living situation. The stress experienced during pregnancy triggers a biological response in the mother which can transfer stress to the fetus through hormones like cortisol and adrenaline, serotonin, cytokines, reactive oxygen species, or the gut microbiota. This transfer of stress can induce alterations in fetal development, predisposing offspring of stressed mothers to developing gastrointestinal (GI) disorders such as colitis or Irritable Bowel Syndrome (IBS), specifically through gut dysbiosis. Ongoing research is necessary to determine the biological mechanisms of stress transfer, and how probiotic treatments may be used to correct dysbiosis and prevent or treat GI disorders.