A series of experiments were conducted to examine the effect of chemical composition of the diet on intestinal <i>Clostridium perfringens</i> populations and necrotic enteritis (NE) in broiler chickens. In the first experiment, birds were fed high concentrations of dietary protein (fish meal or soy protein concentrate) and soluble fiber (guar gum). Clinical NE was not observed, however, there was a high level of <i>C. perfringen</i> colonization especially in guar gum fed birds. The next set of experiments examined the effect of various levels of DL-Met or MHA-FA on <i>C. perfringen</i> and other intestinal microbes. These experiments demonstrated a significant reduction (P < 0.05) in <i>C. perfringen</i> growth with methionine supplementation in ileum and cecum. The results suggest that both DL-Met and MHA-FA may reduce intestinal populations of <i>C. perfringen</i> in broiler chickens when used in high concentrations. The next three experiments were conducted to examine the effect of dietary glycine levels on gut <i>C. perfringen</i> populations, α-toxin production and NE lesion scores. Majority of birds showed clinical signs of disease with 4.16-8.33% mortality. There was a direct correlation between intestinal <i>C. perfringen</i> populations, NE lesions scores and mortality with dietary glycine level. However, due to the use of gelatin as the dietary source of glycine in these experiments, the diets also contained high proline levels which confounded our results. The last study was conducted to establish a direct causative relationship between dietary glycine concentration and <i>C. perfringen</i> growth and/or NE in broiler chickens using encapsulated amino acids. Birds fed diets containing high levels of encapsulated glycine had higher NE lesion scores than those fed encapsulated proline or no encapsulated amino acids, thus demonstrating a direct effect of glycine on intestinal <i>C. perfringen</i> growth. It is concluded that amino acid composition of dietary protein is an important determinant of intestinal microbial growth, particularly <i>C. perfringen</i>, and could affect incidence of NE in broiler chickens.
Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:SSU.etd-05102007-194124 |
Date | 14 May 2007 |
Creators | Dahiya, Jaipal |
Contributors | Van Kessel, Andrew G., Olkowski, Andrew A., Gomis, Susantha, Drew, Murray D., Classen, Henry L. (Hank), Buchanan, Fiona C. |
Publisher | University of Saskatchewan |
Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
Language | English |
Detected Language | English |
Type | text |
Format | application/pdf |
Source | http://library.usask.ca/theses/available/etd-05102007-194124/ |
Rights | unrestricted, I hereby certify that, if appropriate, I have obtained and attached hereto a written permission statement from the owner(s) of each third party copyrighted matter to be included in my thesis, dissertation, or project report, allowing distribution as specified below. I certify that the version I submitted is the same as that approved by my advisory committee. I hereby grant to University of Saskatchewan or its agents the non-exclusive license to archive and make accessible, under the conditions specified below, my thesis, dissertation, or project report in whole or in part in all forms of media, now or hereafter known. I retain all other ownership rights to the copyright of the thesis, dissertation or project report. I also retain the right to use in future works (such as articles or books) all or part of this thesis, dissertation, or project report. |
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