Diet affects gastrointestinal permeability in yearling Quarter Horses

Open Access
- Author:
- Norris, Kathryn Gilliam
- Graduate Program:
- Animal Science
- Degree:
- Master of Science
- Document Type:
- Master Thesis
- Date of Defense:
- July 03, 2013
- Committee Members:
- William Staniar, Thesis Advisor/Co-Advisor
Robert John Vansaun, Thesis Advisor/Co-Advisor
Ryan John Elias, Thesis Advisor/Co-Advisor
Dr Samantha A Brooks, Thesis Advisor/Co-Advisor - Keywords:
- sugar absorption tests
high starch
nutrition
horse
restricted forage - Abstract:
- Increased gastrointestinal permeability in mammalian species has been shown to induce a variety of health consequences, and the capability to quantify and detect changes in gastrointestinal permeability is critical in understanding complex gastrointestinal disorders. In the horse specifically, the involvement of epithelial cell and tight junctional deterioration are hypothesized in the etiologies of laminitis induction, colic, and ulceration throughout the gastrointestinal tract. In this work, two forms of bovine colostrum were hypothesized to mitigate the predicted increase in gastrointestinal permeability induced by high starch, low forage diets in long Quarter Horse yearlings. In order to address this hypothesis, the optimization and validation of sugar absorption tests (SAT) in the horse as a measure of gastrointestinal permeability were performed. Nine Quarter Horse yearlings were utilized in a repeated Latin square design, which consisted of three 28 d periods. Each period contained one 14 d low concentrate high forage (LCHF) washout interval and one 14 d high concentrate low forage (HCLF) treatment interval. During the HCLF treatment intervals, yearlings were placed in one of three supplemental groups: whole bovine colostrum (WBC), concentrated bovine colostrum (CBC), or no supplement (NC), with each yearling receiving each supplement once throughout the study. Weekly fecal pH measurements were taken along with bi-weekly meal response measurements for both packed cell volume (PCV) and total plasma protein (TPP). At the conclusion of each two-week period a SAT was performed on each animal. Intricacies involving useful sugar marker dose, appropriate feeding protocol, urine collection and preservation, alditol acetate preparation for analysis, and protocols for gas chromatography with flame ionization detection of urine sugar markers have been included as a part of validation of this technique in the horse. The SAT involved a sixteen-hour fast followed by administration of sugar markers via nasogastric tube to initiate a 24-hour total collection of urine. Fecal pH was lower on the HCLF (6.53 ± 0.04) diet in comparison to the LCHF diet (6.95 ± 0.04) (P < 0.0001). Irrespective of diet, fecal pH was lower on day 14 than on day 7 of each interval (P < 0.0001). Fecal pH from day 7 to day 14 while horses were fed the LCHF diet decreased from 7.08 ± 0.05 to 6.81 ± 0.05 (P = 0.0003). Fecal pH from day 7 to day 14 while horses were fed the HCLF diet decreased from 6.64 ± 0.05 to 6.43 ± 0.05. Packed cell volume decreased in response to concentrate meal to a greater extent on the HCLF diet (P < 0.0381), while meal response change of TPP was not affected by diet. Body temperature increased 0.304° F during the HCLF diet and 0.017° F during the LCHF diet when compared to an average measure during the LCHF intervals (P < 0.0001). The percent excretion of oral dose for sucrose, lactulose, mannitol, and sucralose was not different during the 24-hour urine collection for supplement treatments (P > 0.10). The data within the smaller 6-hour urine collections supports future investigation of CBC as a potential gastrointestinal health supplement. The percent excretion of oral dose of sucrose, lactulose, and mannitol when fed the HCLF diet indicate an increase in gastrointestinal permeability in comparison to intervals when fed the LCHF diet (P < 0.05). This study provides a preliminary evaluation of changes in equine gastrointestinal permeability due to diet and supports numerous studies that hypothesize high starch, low forage diets influence gastrointestinal health.