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The effects of supplementation of a Saccharomyces cerevisiae fermentation product and reducing dietary starch content after calving on the immune response and nutrient digestibility in transition dairy cows

  • Author / Creator
    Knoblock, Caroline
  • The transition period is a challenging time for dairy cows because they experience reduced immune system function, increased risk of sub-acute rumen acidosis, and inflammation. The combination of these can lead to increased susceptibility to disease and reduced productivity. Additionally, incidence of sub-acute rumen acidosis is associated with reduced nutrient digestibility. The objective of this thesis was to evaluate the effects of supplementation of a Saccharomyces cerevisiae fermentation product (SCFP) and decreasing dietary starch content on gene expression in rumen papillae, serum concentrations of acute phase proteins, indicators of oxidative stress in plasma, adaptive immune response, and nutrient digestibility in transition dairy cows. Holstein dairy cows (n = 38) were fed a Saccharomyces cerevisiae fermentation product (SCFP, NutriTek®, Diamond V, Cedar Rapids, IA) during the transition period. Four weeks before calving, cows were fed a common close up diet containing 13% starch with or without SCFP. For 3 weeks after calving, cows were fed high or low starch (HS vs. LS; 27 and 21%, respectively) diets with or without SCFP (CON). Animals were assigned to one of 4 treatments (CON+HS, CON+LS, SCFP+HS, SCFP+LS). After week 3, all animals received high starch diets with or without SCFP. Rumen papillae samples were collected at d -10 relative to expected calving date and d 21 ± 3 after calving and analyzed for mRNA abundance using qRT-PCR. Acute phase protein concentrations in serum and indicators of oxidative stress in plasma were measured on d -10 relative to expected calving date and on d 1, 7, 21, and 42 ± 3. An ovalbumin challenge to measure adaptive immune response was conducted on d 7 and 21 ± 3 after calving. Nutrient digestibility was measured on d 7 and 21 ± 3 after calving. There was no interaction between starch content and SCFP treatments on mRNA abundance, acute phase response, adaptive immunity, or nutrient digestibility. There was an interaction between dietary starch content and SCFP on indices of oxidative stress. Supplementation of SCFP tended to reduce plasma concentrations of total antioxidant capacity on d 1 and 7 after calving regardless of starch content of fresh diets, and d 21 after calving when low starch diets were fed. Similarly, regardless of starch content of fresh diets, SCFP supplementation increased plasma concentrations of malondialdehyde on d 21 after calving as compared to diets without SCFP, indicating that animals fed SCFP experienced greater oxidative stress. However, SCFP supplementation reduced serum concentrations of haptoglobin on d 7 after calving, indicating reduced systemic inflammation. Feeding a low starch diet after calving increased apparent total tract neutral detergent fibre digestibility on d 7 after calving and reduced mRNA abundance of interleukin receptor associated kinase-1in rumen tissue on d 21 after calving, suggesting reduced immune activation in rumen tissue. There was no effect of treatment on adaptive immunity. These results indicate that supplementing SCFP through the transition period and feeding a low starch diet after calving may reduce inflammation.

  • Subjects / Keywords
  • Graduation date
    Fall 2018
  • Type of Item
    Thesis
  • Degree
    Master of Science
  • DOI
    https://doi.org/10.7939/R35Q4S29X
  • License
    Permission is hereby granted to the University of Alberta Libraries to reproduce single copies of this thesis and to lend or sell such copies for private, scholarly or scientific research purposes only. Where the thesis is converted to, or otherwise made available in digital form, the University of Alberta will advise potential users of the thesis of these terms. The author reserves all other publication and other rights in association with the copyright in the thesis and, except as herein before provided, neither the thesis nor any substantial portion thereof may be printed or otherwise reproduced in any material form whatsoever without the author's prior written permission.