The transition from a lipid-rich in-ovo environment to a carbohydrate- and protein-rich diet is perhaps the biggest challenge that hatchlings must overcome during early life. Amniotic fluid supplementation of the late-term avian embryo (i.e. in-ovo feeding â IOF) stimulates enteric maturation of poultry and alleviates the stress of hatching. Because rapidly dividing cells (e.g. intestinal epithelial cells) require an exogenous supply of nucleotides, dietary nucleotide supplementation can improve the enteric maturation post-hatch. Our working hypothesis was that nutritional strategies influencing in-ovo nutrition and post-hatch dietary feed intake enhance the enteric development in perinatal turkey embryos and poults. Our study was among the first to characterize the ultra-structural changes in the small intestinal mucosa of the perinatal turkey embryo and poult (Chapter II). Moreover, electron microscopy revealed that microbial colonization in the avian digestive tract begins prior to hatch as early as 17E. Molecular profiling of these bacteria confirmed that some the species include Bacillus, Lactobacilli, Pseudomonas and several uncultured bacteria (Chapter III). We showed that IOF accelerates the ultra-structural maturation of the jejunum mucosa of turkey embryos and poults around the time of hatch, and these effects are associated with elevated plasma triiodothyronine (T3) levels, a potent stimulator of morphological development of the mucosa (Chapter IV). Finally, we showed that dietary nucleotide supplementation to IOF turkey poults enhances the enteric maturation after hatch and the positive effects of nucleotide supplementation appear to be associated with stimulation of feed intake post-hatch. Therefore, we concluded that: (1) profound ultra-structural adaptations of the intestinal mucosa coincide with the imbibition of the amniotic fluid by the embryo; (2) microflora colonization of the avian gut begins well before hatch, (3) IOF stimulates ultra-structural maturation of the small intestine at hatch and these effects involve up-regulation of genes mediating epithelial cell proliferation as well as higher T3 levels. (4) Dietary nucleotide supplementation of IOF turkey poults enhances enteric maturation post-hatch, which coincide with a consistent stimulation of poults appetite by dietary nucleotide supplementation.
| Identifer | oai:union.ndltd.org:NCSU/oai:NCSU:etd-12042009-080316 |
| Date | 11 January 2010 |
| Creators | Bohórquez, Diego V |
| Contributors | Peter R. Ferket |
| Publisher | NCSU |
| Source Sets | North Carolina State University |
| Language | English |
| Detected Language | English |
| Type | text |
| Format | application/pdf |
| Source | http://www.lib.ncsu.edu/theses/available/etd-12042009-080316/ |
| 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, dis sertation, 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 NC State University 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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