The objectives of this study were to investigate the effects of autoclave heating on the rumen protein degradation characteristics of flaxseed (<i>Linum usitatissimum</i>, cv. Vimy), and to compare them to differences in diffuse reflectance infrared Fourier transform (DRIFT) and Synchrotron based Fourier transform infrared microspectroscopy (S-FTIR) measurements of the protein alpha-helix to beta-sheet ratios. Hierarchical cluster analysis (CLA) and principal components analysis (PCA) were also conducted to identify differences in the DRIFT spectra. Flaxseed samples were kept raw for control or autoclaved in batches at 120°C for 20, 40 or 60 min for treatments 1, 2 and 3, respectively. The rumen degradation kinetics of protein were measured along with the protein sub-fractions of the Cornell net carbohydrate and protein system (CNCPS), and chemical composition. Intestinal digestibility was determined using the three-step procedure outlined by Calsamiglia and Stern (1995). Protein supply to the small intestine was determined using the NRC (2001) and DVE/OEB models. The results showed that heating increased dry matter (DM) and ether extract (EE) content, while reducing neutral detergent fibre (NDF) and acid detergent fibre (ADF), with little numerical difference between the three treatments. Soluble crude protein (SCP) also decreased upon autoclaving with concomitant increases in non-protein nitrogen (NPN), neutral detergent insoluble nitrogen (NDIN) and acid detergent insoluble nitrogen (ADIN). The CNCPS protein sub-fractions with the greatest changes were the buffer-soluble true protein fraction (PB1) and the fraction representing buffer-insoluble true protein which is not bound to NDF (PB2) showing dramatic increases, indicating a decrease in the overall protein degradability. <i>In situ</i>experiments showed a reduction in effective degradable dry matter (EDDM) as well as a reduction in effective degradable crude protein (EDCP) without significant differences between the treatments. Intestinal digestibility of protein as estimated by the three-step procedure showed no changes upon autoclaving. Modeling results, with flaxseed as the only feed source, for absorbable ruminally-undegraded feed protein in the intestines using both the NRC (2001) and DVE/OEB systems showed increases as a consequence of the autoclave treatments but again there were no differences between the treatments. The degraded protein balance results showed for both the NRC (2001) and DVE/OEB models that both were decreased upon autoclave treatment. However, the values for the NRC (2001) model suggested a potential nitrogen (N) deficiency and, therefore potentially impaired microbial crude protein (MCP) production, whereas the values for the DVE/OEB system showed potential N excess and, therefore, possible loss from the rumen. DRIFT analysis of protein secondary structure ratios showed a decrease in the alpha-helix to beta-sheet ratio for the whole seed, whereas results from S-FTIR spot data for cotyledon tissue showed autoclaving had the opposite effect on the ratio. CLA and PCA were successfully used to make distinctions between the different treatment spectra and showed enhanced sensitivity upon selection of a smaller spectral window to include only the amide I and II portion of the IR spectrum. The results failed to demonstrate any differences between the autoclave treatments used in this study, and showed that autoclaving generally decreased effectively ruminal degradability of flaxseed protein. The results further indicated that autoclaving had a significant enough effect on the flaxseed to permit identification of the altered alpha-helix to beta-sheet ratio with the mid-IR spectrum, as well as differentiation between the treatments using PCA and CLA. PCA and CLA results suggest that mid-IR spectral methods are more sensitive than traditional methods when used to identify differences between the heat treatments.

Four lactating Holstein cows fitted with ruminal and duodenal cannulae were used in a 4 x 4 Latin square design to determine the effects of feeding raw and heat-treated flaxseed on ruminal fermentation parameters, ruminal fatty acid biohydrogenation (BH), nutrient utilization in various segments of the gastrointestinal tract, and plasma and milk composition of lactating dairy cows. Four diets were formulated: a control diet with no flaxseed (C); a raw flaxseed (RF); a micronized flaxseed (MF); and an extruded flaxseed (EF) diet. Ruminal pH, NH3N and total volatile fatty acids were not affected by dietary treatments. However, feeding flaxseed decreased ( P < 0.01) molar proportion of acetate and increased ( P < 0.01) that of propionate. Ruminal fiber digestion was lower (P < 0.04) for cows fed the flaxseed diets relative to those fed C. Feeding flaxseed had no effect on milk yield, milk fat and protein content, and milk fat yield, but decreased (P = 0.02) milk protein yield. (Abstract shortened by UMI.)

Experiments were conducted to assess the effect of feeding diets containing ground flaxseed (FS); as a source of α-linolenic acid (18:3n-3), on whole body retention efficiency (RE) and disappearance (indirect measure of oxidation) of 18:3n-3, and apparent conversion (AC) of 18:3n-3 to n-3 highly unsaturated fatty acids (HUFA) in growing female pigs, using the mass balance approach (serial slaughter). Oxidation of 18:3n-3 was determined directly based on feeding U-13C-18:3n-3 and appearance of 13C in expired breath. Growth performance, composition of growth, body composition, and carcass and loin meat characteristics were not affected by feeding FS containing diets (P > 0.10). In selective pork cuts and the whole body, feeding FS increased (P < 0.10) the contents of 18:3n-3, eicosatrienoic acid (20:3n-3), eicosapentaenoic acid (20:5n-3), and docosapentaenoic acid (22:5n-3) but not docosahexaenoic acid (22:6n-3; P > 0.10). Expressed as a proportion of intake, RE of 18:3n-3 declined with duration of feeding FS (d 0 to 15 vs. d 15 to 30; P = 0.098; 68.4 vs. 52.8%). Similarly, the AC of 18:3n-3 to 20:3n-3 (8.87 vs. 5.53%) and 22:6n-3 (1.27 vs. 0.54%) was reduced over time (P < 0.05), whereas disappearance of 18:3n-3 increased over time (P = 0.074; 2.12 vs. 23.7%). At similar cumulative intake of 18:3n-3, stage of growth (25 to 50 vs. 85 to 110 kg BW) did not impact (P > 0.10) RE of 18:3n-3 and the sum of all n-3 polyunsaturated (PUFA; 95 vs. 110%), AC of 18:3n-3 to n-3 HUFA (19 vs. 22%), and oxidation of 18:3n-3 (7.0 vs. 5.6%); these parameters were influenced by dietary 18:3n-3 level. Pigs fed low dietary 18:3n-3 (0.8 g/kg) yielded both higher RE and AC of 18:3n-3 to n-3 HUFA than pigs on high dietary 18:3n-3 intake (15 g/kg). Oxidation of 18:3n-3 tended to increase with dietary 18:3n-3 level (P = 0.077; 7.97 vs. 4.67% for pigs on high and low dietary 18:3n-3, respectively) and was not affected by previous 18:3n-3 intake (P > 0.10). Feeding modest amounts of FS leads to a substantial and predictable enrichment of n-3 PUFA in pork without compromising carcass and meat quality. The content of n-3 PUFA appears to be independent of timing of feeding n-3 PUFA, providing flexibility as to when n-3 PUFA can be fed for generating n-3 PUFA enriched, value added pork. / Ontario Pork, Ontario Ministry of Agriculture, Food and Rural Affairs, Agricultural and Agri-Food Canada, and Natural Sciences and Engineering Research Council of Canada.

A series of experiments were carved out to study the effect of dietary enzyme inclusion or flaxseed processing on feeding value of flaxseed for broilers. The feed enzymes tested containing xylanase activities failed to produce any positive performance response when used in a 10% flaxseed diet with manufacturer recommended dosage for broilers (D 1 to 21). / Autoclaving of flaxseed at 16.5 kg/cm2 and 120°C for 15 min slightly improved the performance of young broilers fed a 10% flaxseed diet. This improvement was not observed at lower temperature and shorter period of autoclaving, but was magnified at higher flaxseed level. Autoclaving, microwave roasting, pelleting significantly (P < 0.05) reduced HCN content in flaxseed. The greatest HCN reduction was observed with repeated pelleting (54.9%) and microwave roasting (83.2%), from its 377 mg/kg of raw flaxseed. / When tested with roosters, flaxseed processing effectively increased ME values, dry matter, and ether extract utilization. The raw flaxseed TME and TMEn of 3343 and 3225 kcal/kg, respectively, was significantly (P < 0.01) increased by repeated pelleting (44%) and microwave roasting (32%). It was the result of significant improvement (P < 0.05) of EE utilization by the relevant processing. These improvements had a similar effect on total FA and linolenic acid utilization. / The processing method and flaxseed level had a very significant effect on deposition of total T-3 FAs in breast and thigh meat (P < 0.001) of 40 days old broilers. The highest level of T-3 FAs in muscle lipids of 23.04% and 26.46% for breast and thigh, respectively, was achieved with the highest flaxseed level (14% in days 1 to 21 days, and 17% in days 22--40) and pellet-then-mash processing, which lead to low T-6/T-3 ratios of 0.81 and 0.80 in breast and thigh muscle lipid, respectively. The proper flaxseed processing allowed more flaxseed (up to 12%) to be included in broiler diets without obvious growth depression, while achieving the higher desired T-3 FAs deposition in meat.

A study was conducted to examine the response to feeding flaxseed (FS) and probiotics on plasma and egg yolk cholesterol and plasma fatty acid profile in laying hens. A total of 576 Single Comb White Leghorn hens (SCWL) at 26 weeks of age were fed diets containing 15% FS and a corn-soybean meal diet (C) supplemented with and without ferlac 25 (F25) or Lactobacillus acidophilus (LA). Feed consumption was significantly (p < 0.05) increased by FS supplemented with both F25 and LA. Dietary treatments had no significant (p > 0.05) effect on feed conversion. Egg production was significantly (p < 0.05) higher among the FS probiotic supplemented diets and significantly (p < 0.05) lower for dietary FS supplemented with LA. However, egg yolk weight did not respond to dietary treatments (p > 0.05). Body weight was significantly low for all FS fed groups. Shell thickness was not statistically significant (p > 0.05) among experimental treatments, while haugh units were significantly (p < 0.05) higher for FS group supplemented with LA. Probiotic supplementation significantly (p < 0.05) reduced plasma cholesterol (CHL) from 161mg/dL in C diet to 117mg/dL in probiotic supplemented groups. Plasma triglycerides (TG) were significantly (p < 0.05) reduced from 2.8g/dL in FS to 1.9g/dL in probiotic supplemented groups while egg yolk CHL was significantly (p < 0.05) reduced by probiotic supplementation on FS treatments from 14.04mg/g in FS fed group to 10.16mg/g in LA supplemented FS group. Fatty acids profile in the egg yolk responded significantly (p < 0.05) to dietary treatments. FS treatments with and without probiotic supplementation significantly reduced C18:1 o-9 by 12%; while the PUFA families (o-3 and o-6) were significantly (p < 0.05) increased in FS fed group by 93% and 18%, respectively. C20:4, o-6 was significantly reduced from 6.6mg/g in the C group to 3.96mg/g in Fs groups. (Abstract shortened by UMI.)

A study was conducted to investigate the effect of supplemental fat from flaxseed (FL) on fatty acid (FA) profile, chemical composition, energy value of colostrum and milk, and litter performance. On day 107 of gestation a total of 59 large white sows were selected, blocked by parity and randomly allotted to one of three diets, 15% flaxseed (FL), 10% fullfat soybean (SB) or a control commercial (CO) diet containing corn and soybean meal. Diets were isocaloric and isonitrogenous but differed in fat content and FA composition. Colostrum and milk were collected soon after farrowing and on day 7, respectively, for fatty acid and chemical analysis. Dietary treatments did not affect sow feed consumption, weight loss, number of live pig born and weaned per litter. Similarly, pig birth weights, and day 7, 14, and 21 weights did not differ among treatment groups. FL significantly (p < 0.05) increased linolenic (LNA C18:3co3) and decreased palmitic (C16:0) and oleic (C18:1) acids in colostrum. FL also significantly (p < 0.001) increased LNA and arachidonic acid (C20:4) in milk, while it decreased myristic (C14:0), palmitic and palmitoleic (C16:1) acids. Chemical analysis showed no significant differences in total solids (TS) and energy value of colostrum while a significant (p < 0.05) increase in TS, fat concentration and energy value was observed in milk from FL. A total of 335 piglets were used in the plasma study of lipid metabolites. Triglyceride (TG), cholesterol, HDL cholesterol and glucose were not affected by dietary treatment (p > 0.05). Feeding FL to sows during late gestation and lactation enriches sow milk and piglets with LNA.

Thesis (M.S.)--University of Missouri-Columbia, 2004. / Typescript. Includes bibliographical references (leaves 203-218). Also available on the Internet.

Thesis (M.S.)--University of Missouri-Columbia, 2004. / Typescript. Includes bibliographical references (leaves 203-218). Also available on the Internet.

Thesis (doctoral)--Helsinki University of Technology, 2005. / Includes bibliographical references. Also available on the World Wide Web. Myös verkkojulkaisuna.

Epithelial ovarian cancer is the most lethal gynecologic malignancy, with a 5-year survival rate of less than 40%. This is due in part to a lack of early detection markers and lack of specific symptoms during early disease. The laying hen is the only accessible animal model which develops epithelial ovarian cancer spontaneously, with features closely resembling the human disease. It has been estimated that approximately 30% of all cancers can be prevented with diet, exercise, and maintenance of an optimal weight, and the chronic low-grade inflammation that accompanies obesity is implicated as a causal factor in the development of cancer. Flaxseed, a rich plant source of anti-inflammatory omega-3 fatty acids and lignans which act as phytoestrogens and antioxidants, exhibits chemosuppressive effects against the development and progression of ovarian cancer. We have shown that a diet of 10% flaxseed reduces the incidence and severity of ovarian cancer when fed to laying hens over 4 years, due in part to the ability of flaxseed to suppress the production of proinflammatory PGE2 in the ovary by decreasing expression of COX enzymes. To investigate other potential specific mechanisms by which flaxseed acts to suppress ovarian cancer, we examined expression and activity of pathways known to be involved in the etiology and progression of human epithelial ovarian cancer in ovarian cancer in the laying hen, and determined whether flaxseed affected these pathways during cancer development. We investigated the effect of flaxseed and its individual components upon oxidative stress in the normal ovary and in ovarian cancer by analyzing expression of target genes of the NRF2 transcription factor. The NRF2 pathway is a "master switch" that regulates expression of ROS-responsive detoxification genes. Results revealed that expression of four genes was significantly downregulated in then ovaries of hens on the defatted flaxmeal (DFM) and whole flaxseed (WF) diets compared to hens on diets that are high in pro-inflammatory omega-6 fatty acids, suggesting that flaxseed decreases oxidative stress in the ovary. Conversely, one target gene was upregulated in ovarian cancer compared to normal ovaries, and this observation was not affected by flaxseed. Additionally, nuclear accumulation Nrf2 protein was not observed in tumor cells, suggesting that flaxseed does not exert chemosuppressive effects by modulating NRF2 signaling in ovarian cancer. To further investigate pathways potentially regulated by flaxseed, we performed a microarray with 44k features and found that a set of genes involved in branching morphogenesis was upregulated in ovarian cancer and significantly decreased by flaxseed, including E-cadherin and miR-200, suggesting that flaxseed impedes the activity of an aberrantly activated developmental program that controls gland formation during ovarian cancer progression. Lack of nuclear accumulation of ZEB1 protein in tumor cells suggests that this decrease in expression is likely not due to EMT. Finally, due to its known roles in controlling developmental programs such as EMT as well as regulating cell growth and proliferation, we performed a set of experiments to examine activity of the TGF-beta pathway. PCR array analysis revealed that SMAD target genes, ligands, receptors, and co-regulatory proteins were upregulated in ovarian tumors from hens on both diet groups, suggesting TGF-beta signaling is enhanced in ovarian cancer. However, expression of SMAD6 and SMAD7 was upregulated in tumors from hens on the flaxseed diet but not control diet, with SMAD7 protein being expressed in both epithelial tumor cells and intratumoral stromal cells. Additionally, immunohistochemical staining for pSMAD2/3 was decreased in epithelial tumor cells and absent from intratumoral stromal cells in tumors from hens on the flaxseed diet compared to tumors from hens on the control diet, and these data together suggest that flaxseed may inhibit pro-oncogenic TGF-beta signaling in ovarian cancer. Finally, flaxseed prevents the downregulation of expression of p15 and the upregulation of CCNA and CCNE in ovarian tumors, suggesting that flaxseed may slow cell cycle progression. Data from these studies provides preliminary evidence that flaxseed exerts pleiotropic effects upon gene expression to negatively regulate pathways driving the progression of ovarian cancer, including aberrant TGF-beta signaling and glandular development. These studies provide groundwork for in vitro studies to test the specific effects of flaxseed upon proteins involved in TGF-beta signaling and upon the expansion of tumor epithelia.