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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
231

Evaluation of the effect of dietary forage and concentrate levels on the fatty acid profile of bison tissue

Turner, Tyler 04 January 2006
The effects of feeding strategy on subcutaneous, perirenal adipose tissue and ribeye (longissimus dorsi) muscle fatty acid profiles were evaluated from 60 bison (Bison bison) bulls from Western Canada. Treatments included Forage Fed (n=19); short term concentrate feeding, <90 Day (n=9); mixed forage and concentrate feeding, 50:50 Forage:Grain (n=20); and Feedlot Finishing (n=12), and were analyzed for interactions and main effects between treatment and tissue type. Saturated fatty acids were found in larger (P<0.05) proportions within perirenal tissue for all treatments. Polyunsaturated fatty acids were concentrated (P<0.05) in the intramuscular tissue. Polyunsaturated fatty acid content was greater (P<0.05) in Forage Fed and 50:50 Forage:Grain than in <90 Day or Feedlot Finishing treatments. The polyunsaturated to saturated fatty acid ratio was greatest (P<0.05) for Forage Fed followed by 50:50 Forage:Grain, with <90 Day and Feedlot Finishing treatments having the lowest ratio. Linoleic acid content within intramuscular tissue was greatest (P<0.05) in the 50:50 Forage:Grain followed by the <90 Day treatment, with the Forage Fed group being intermediate, and the Feedlot Finishing being the lowest (P<0.05). Subcutaneous tissue contained more (P<0.05) conjugated linoleic c-9, t-11 acid than did intramuscular tissue. The conjugated linoleic c-9, t-11 acid content of intramuscular tissue was greater (P<0.05) in the Forage Fed and <90 Day treatments than in the 50:50 Forage:Grain and Feedlot Finishing treatments. Alpha-linolenic acid content was greatest (P<0.05) in intramuscular tissue of Forage Fed bison than the other treatments. Total omega-3 fatty acid concentration was greater (P<0.05), in the intramuscular tissue of Forage Fed bison, followed by <90 Day and 50:50 Forage:Grain being similar (P>0.05) with Feedlot Finishing having the lowest (P<0.05) content. Eicosapentaenoic, docosapentaenoic, and docosahexaenoic acid were all found in the greatest (P<0.05) proportion in the Forage Fed, and least (P<0.05) in the Feedlot Finishing treatment. </p> <p>The total omega-6 and arachidonic fatty acid content of intramuscular tissue was greater (P<0.05) in the Forage Fed and 50:50 Forage:Grain than in the <90 Day or Feedlot Finishing treatments. The omega-6 to omega-3 fatty acid ratio was greatest (P<0.05) for the 50:50 Forage:Grain followed by <90 Day with Feedlot Finishing being intermediate, and Forage Fed bison having the lowest (P<0.05) ratio. </p><p>Feedlot bison were compared to beef (<i>Bos taurus</i>) steers (n=4) and sheep wethers (<i>Ovis aries</i>) (n=3). Sheep had lower (P<0.05) saturated fatty acid content than did bison or beef in intramuscular tissue. Polyunsaturated fatty acid content of intramuscular tissue was greater (P<0.05) in bison than in beef or sheep. The ratio of polyunsaturated to saturated fatty acids was greater (P<0.05) for bison than for beef or sheep. The omega-6 to omega-3 fatty acid ratio was lower (P<0.05) for the bison than the beef, while sheep were intermediate (P<0.05).</p><p>Forage Fed bison compared to forage fed sheep wethers (n=3) showed that the ratio of polyunsaturated to saturated fatty acids was greater (P<0.05) in bison than sheep. The ratio of omega-6 to omega-3 fatty acids was similar (P>0.05) for both species.</p><p>Forage Fed bison yielded the greatest proportion of beneficial fatty acids amongst the bison treatments. Comparison of species under feedlot and forage finishing systems indicated bison to have a more desirable fatty acid profile than did beef or sheep finished under their respective systems.
232

Fatty acid composition in diverse oat germplasm

Dhanda, Rohit Kumar 24 March 2011
Oat is an important crop for livestock feed and human food. Increased interest in the health promoting properties of oat has led to a need to explore diverse oat germplasm for improved nutritional quality. One target for improved nutritional quality could be an altered fatty acid composition. A study was conducted to explore the fatty acid profile of diverse accessions from the world oat collection preserved in the Canadian national seed genebank, Plant Gene Resources of Canada (PGRC), at the Agriculture and Agri-Food Canada (AAFC) Research Centre, Saskatoon, Saskatchewan, Canada and genotypes from the Crop Development Centre (CDC), University of Saskatchewan, Saskatoon and the Eastern Cereal and Oilseed Research Centre (ECORC), AAFC, Ottawa, Canada. Accessions included a wide range of Avena sativa L. and other selected species from the genus Avena (A. byzantina C. Koch, A. sterilis L., A. fatua L., A. sativa subsp. nudisativa (Husn.) Rod. et. Sold. and A. strigosa Schreb.). The fatty acid profiles of 917 oat accessions from these taxa were analyzed using gas chromatography, revealing significant variability for the three major fatty acids in oat oil. Oleic and linoleic acid demonstrated the greatest variation. A few A. sativa accessions had higher oleic and lower palmitic acid levels compared to the general average. Some hexaploid wild oat accessions (A. sterilis) showed relatively high oleic and below average levels of palmitic and linoleic acid compared to A. sativa. A. strigosa accessions had consistently higher levels of oleic acid than other Avena species. Based on initial results, 52 selected A. sativa accessions were grown in 2009 in replicated field trials and re-evaluated to gain insight into the influence of the growing environment on fatty acid composition. Fatty acid composition was affected by genotype, whereas location significantly affected palmitic and oleic acid content. Correlations were determined among the contents of the six fatty acids, oil content and protein content. Oleic acid content was positively correlated with oil content, which may be particularly important to plant breeders for nutritional quality improvement of future oat cultivars. The understanding gained from this research suggests the possibility of improving the fatty acid profile of future oat cultivars for food and feed.
233

Evaluation of the effect of dietary forage and concentrate levels on the fatty acid profile of bison tissue

Turner, Tyler 04 January 2006 (has links)
The effects of feeding strategy on subcutaneous, perirenal adipose tissue and ribeye (longissimus dorsi) muscle fatty acid profiles were evaluated from 60 bison (Bison bison) bulls from Western Canada. Treatments included Forage Fed (n=19); short term concentrate feeding, <90 Day (n=9); mixed forage and concentrate feeding, 50:50 Forage:Grain (n=20); and Feedlot Finishing (n=12), and were analyzed for interactions and main effects between treatment and tissue type. Saturated fatty acids were found in larger (P<0.05) proportions within perirenal tissue for all treatments. Polyunsaturated fatty acids were concentrated (P<0.05) in the intramuscular tissue. Polyunsaturated fatty acid content was greater (P<0.05) in Forage Fed and 50:50 Forage:Grain than in <90 Day or Feedlot Finishing treatments. The polyunsaturated to saturated fatty acid ratio was greatest (P<0.05) for Forage Fed followed by 50:50 Forage:Grain, with <90 Day and Feedlot Finishing treatments having the lowest ratio. Linoleic acid content within intramuscular tissue was greatest (P<0.05) in the 50:50 Forage:Grain followed by the <90 Day treatment, with the Forage Fed group being intermediate, and the Feedlot Finishing being the lowest (P<0.05). Subcutaneous tissue contained more (P<0.05) conjugated linoleic c-9, t-11 acid than did intramuscular tissue. The conjugated linoleic c-9, t-11 acid content of intramuscular tissue was greater (P<0.05) in the Forage Fed and <90 Day treatments than in the 50:50 Forage:Grain and Feedlot Finishing treatments. Alpha-linolenic acid content was greatest (P<0.05) in intramuscular tissue of Forage Fed bison than the other treatments. Total omega-3 fatty acid concentration was greater (P<0.05), in the intramuscular tissue of Forage Fed bison, followed by <90 Day and 50:50 Forage:Grain being similar (P>0.05) with Feedlot Finishing having the lowest (P<0.05) content. Eicosapentaenoic, docosapentaenoic, and docosahexaenoic acid were all found in the greatest (P<0.05) proportion in the Forage Fed, and least (P<0.05) in the Feedlot Finishing treatment. </p> <p>The total omega-6 and arachidonic fatty acid content of intramuscular tissue was greater (P<0.05) in the Forage Fed and 50:50 Forage:Grain than in the <90 Day or Feedlot Finishing treatments. The omega-6 to omega-3 fatty acid ratio was greatest (P<0.05) for the 50:50 Forage:Grain followed by <90 Day with Feedlot Finishing being intermediate, and Forage Fed bison having the lowest (P<0.05) ratio. </p><p>Feedlot bison were compared to beef (<i>Bos taurus</i>) steers (n=4) and sheep wethers (<i>Ovis aries</i>) (n=3). Sheep had lower (P<0.05) saturated fatty acid content than did bison or beef in intramuscular tissue. Polyunsaturated fatty acid content of intramuscular tissue was greater (P<0.05) in bison than in beef or sheep. The ratio of polyunsaturated to saturated fatty acids was greater (P<0.05) for bison than for beef or sheep. The omega-6 to omega-3 fatty acid ratio was lower (P<0.05) for the bison than the beef, while sheep were intermediate (P<0.05).</p><p>Forage Fed bison compared to forage fed sheep wethers (n=3) showed that the ratio of polyunsaturated to saturated fatty acids was greater (P<0.05) in bison than sheep. The ratio of omega-6 to omega-3 fatty acids was similar (P>0.05) for both species.</p><p>Forage Fed bison yielded the greatest proportion of beneficial fatty acids amongst the bison treatments. Comparison of species under feedlot and forage finishing systems indicated bison to have a more desirable fatty acid profile than did beef or sheep finished under their respective systems.
234

Fatty acid composition in diverse oat germplasm

Dhanda, Rohit Kumar 24 March 2011 (has links)
Oat is an important crop for livestock feed and human food. Increased interest in the health promoting properties of oat has led to a need to explore diverse oat germplasm for improved nutritional quality. One target for improved nutritional quality could be an altered fatty acid composition. A study was conducted to explore the fatty acid profile of diverse accessions from the world oat collection preserved in the Canadian national seed genebank, Plant Gene Resources of Canada (PGRC), at the Agriculture and Agri-Food Canada (AAFC) Research Centre, Saskatoon, Saskatchewan, Canada and genotypes from the Crop Development Centre (CDC), University of Saskatchewan, Saskatoon and the Eastern Cereal and Oilseed Research Centre (ECORC), AAFC, Ottawa, Canada. Accessions included a wide range of Avena sativa L. and other selected species from the genus Avena (A. byzantina C. Koch, A. sterilis L., A. fatua L., A. sativa subsp. nudisativa (Husn.) Rod. et. Sold. and A. strigosa Schreb.). The fatty acid profiles of 917 oat accessions from these taxa were analyzed using gas chromatography, revealing significant variability for the three major fatty acids in oat oil. Oleic and linoleic acid demonstrated the greatest variation. A few A. sativa accessions had higher oleic and lower palmitic acid levels compared to the general average. Some hexaploid wild oat accessions (A. sterilis) showed relatively high oleic and below average levels of palmitic and linoleic acid compared to A. sativa. A. strigosa accessions had consistently higher levels of oleic acid than other Avena species. Based on initial results, 52 selected A. sativa accessions were grown in 2009 in replicated field trials and re-evaluated to gain insight into the influence of the growing environment on fatty acid composition. Fatty acid composition was affected by genotype, whereas location significantly affected palmitic and oleic acid content. Correlations were determined among the contents of the six fatty acids, oil content and protein content. Oleic acid content was positively correlated with oil content, which may be particularly important to plant breeders for nutritional quality improvement of future oat cultivars. The understanding gained from this research suggests the possibility of improving the fatty acid profile of future oat cultivars for food and feed.
235

Molecular reorientation of some fatty acids when in contact with water.

Yiannos, Peter N. 01 January 1960 (has links)
No description available.
236

Cultivar and E-Beam irradiation effects on phytochemical content and antioxidant properties of pecan kernels

Villarreal Lozoya, Jose Emilio 15 May 2009 (has links)
Pecan kernels from six cultivars were analyzed for phenolic content and antioxidant properties. In addition, kernels from two cultivars were irradiated with 0, 1.5 and 3.0 kGy using E-Beam irradiation and stored in accelerated conditions (40 °C and 55% R.H.). Changes in phytochemical profile and antioxidant properties were monitored for 134 days. Cultivars differed greatly in their phytochemical content. Total extractable phenolic content (TP) ranged from 62 to 106 milligrams of chlorogenic acid equivalents per gram of defatted kernel. Antioxidant capacity (AC) measured by the DPPH free radical had a strong correlation with TP. Shells from each cultivar were 6, 4.5 and 18 times greater for TP, AC and condensed tannin content (CT). Gallic and ellagic acids, epicatechin and catechin were identified in hydrolyzed extracts of all cultivars. Prior to hydrolysis, no compounds were positively identified. Fatty acid profile of kernel oil had a strong inverse correlation between oleic and linoleic oil. Kernels from the same cultivar but different location differed in their fatty acid composition but had similar TP. Irradiation of â Kanzaâ and â Desirableâ kernels with 1.5 and 3.0 kGy had no detrimental effects on AC and TP by the end of experiments. Phenolic profile was similar for all treatments. Tocopherol content decreased with irradiation treatments, but no further degradation was observed throughout storage. Peroxide values increased slightly after 98 and 134 days of storage for â Desirableâ kernels, with slight differences between controls and irradiated samples. Color of kernels decreased in lightness and yellowness and increased in redness with no differences between irradiated samples and controls. For the first time the effect of pecan cultivar and E-Beam irradiation was assessed in phytochemical and antioxidant attributes of pecan kernels. Additionally, irradiation with E-Beam had no significant detrimental effects in phytochemical composition and only a slight increase in peroxide value, indicating potential as pecan kernel sanitization.
237

Dietary supplementation of omega-3 fatty acids and subsequent effects on fresh, cooled, and frozen seminal characteristics of stallions

Grady, Sicilia Tatiana 15 May 2009 (has links)
The use of cooled and frozen/thawed semen offers many advantages to breeders. However, many stallions produce spermatozoa that are unable to endure the stresses of cooling/storage and freezing/thawing. Improving the quality and viability of equine spermatozoa via appropriate dietary manipulation could make these stallions commercially viable for cooling or cryopreservation. To evaluate whether spermatozoa quality and viability can be improved by supplementation of omega-3 fatty acids, and if improvements can be made by altering the sources of these fats, nine miniature stallions were placed into 1 of 2 treatment groups and fed either a fish- or algae/flaxseed-based supplement which was added to the basal concentrate. Motion characteristics, membrane integrity and morphology of spermatozoa in fresh, cooled/stored (24 and 48 h), and frozen/thawed semen samples were analyzed. When comparing spermatozoa obtained from stallions in each treatment, no differences were found (P > 0.05) in motility, percentage of membrane intact spermatozoa, and percentage of morphologically normal spermatozoa of stallions. Overall, omega-3 supplementation did not appear to have a beneficial effect on offsetting the harmful effects of the cooling and freezing processes. However, when analyzing the data of one stallion that had < 40% progressive motility (PMOT) after 24 h of cooling and storage, a significant increase was observed in total motility, and progressive motility of fresh and 24 h cooled/stored spermatozoa was observed when supplemented with the fish-based supplement. Thus, omega-3 fatty acid supplementation may be most beneficial for stallions that produce lower quality ejaculates. However, further studies should be conducted, with a larger sample size, in order to substantiate these findings.
238

The isolation and characterisation of fatty acid desaturase genes in cotton

Liu, Qing, January 1998 (has links)
Thesis (Ph. D.)--Faculty of Agriculture, University of Sydney, 1998. / Bibliography: leaves 184-218. Also available in print form.
239

Omega-3 fatty acids website development for registered dietitian education and research

Valverde, Martha M. January 2009 (has links)
Thesis (Ph.D.)--University of Nebraska-Lincoln, 2009. / Title from title screen (site viewed October 15, 2009). PDF text: vii, 163 p. : ill. (some col.) ; 7 Mb. UMI publication number: AAT 3369413. Includes bibliographical references. Also available in microfilm and microfiche formats.
240

Omega-3 enrichment and oxidative stability of broiler chicken meat

Perez De La Ossa, Tulia Ines. January 2009 (has links)
Thesis (M. Sc.)--University of Alberta, 2009. / Title from pdf file main screen (viewed on Jan. 11, 2010). "A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Master of Science in Food Science and Technology, Department of Agricultural, Food and Nutritional Science, University of Alberta." Includes bibliographical references.

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