O aproveitamento de proteína de pescado como coprodutos do processo de industrialização, constitui-se em uma alternativa para a elaboração de produtos com elevada qualidade nutricional. A carne mecanicamente separada (CMS), produzida a partir de carcaças do descarte do processamento de tilápia híbrida vermelha (CMSV), Oreochromis niloticus var. Red Stirling e de tilápia preta (CMSP), Oreochromis niloticus, foram caracterizadas física, química, microbiológica e sensorialmente. Em um primeiro estudo avaliou-se a eficiência de dois tipos de equipamentos de extração mecânica da CMS, rosca- sem-fim e cinta-tambor. Posteriormente, avaliou-se a qualidade da CMS congelada durante 90 dias de armazenamento. Em seguida avaliou-se os atributos sensoriais de cor, odor e aparência da CMSV e CMSP congelada. Para a avaliação do sabor da CMS, foi adicionado ao molho de tomate com CMSV armazenada por 15 e 90 dias e a aceitação avaliada por consumidores. Foi realizado um estudo para avaliação das características de funcionalidade da CMS reestruturada da tilápia híbrida vermelha. O separador tipo rosca-sem-fim apresentou melhor rendimento de extração e controle da temperatura do processo, quando comparado ao separador do tipo cinta-tambor, embora ambos os processos tenham permitido a obtenção de CMS com teores de umidade, proteína e lipídeo adequados para o processamento de coprodutos. A avaliação da vida útil indicou que coprodutos da tilápia híbrida vermelha (CMSV) e tilápia preta (CMSP) apresentaram padrões microbiológicos, valores de pH e oxidação lipídica aceitáveis ao longo do estudo, mesmo apresentado uma descoloração ao longo do armazenamento. A avaliação sensorial para o estabelecimento da vida útil (teste de diferença do controle com provador treinado) foi realizada em períodos até 90 dias. Aos 15 dias de armazenamento, os provadores detectaram diferença significativa, porém o limite sensorial estabelecido pelos provadores (moderadamente diferente do controle) foi atingido aos 60 dias para a CMS da tilápia preta e aos 90 dias para a CMS de tilápia vermelha. A aceitação teve boa resposta, porém a intenção de compra apresentou queda de 19% para o molho adicionado de CMS estocada durante 90 dias. A CMSV é uma matéria prima, com elevado teor proteico (12%) e elevado teor lipídico (15%) e pode ser utilizada para elaboração de diferentes coprodutos. Foi possível obter produto reestruturado com boa funcionalidade tecnológica com adição de 100% de CMS de tilápia híbrida vermelha, o que demonstra a viabilidade de sua utilização, onde apresentaram respostas satisfatórias de rendimento, capacidade de retenção de água e força de penetração no reestruturado. Conclui-se que a CMS das variedades de tilápia estudadas representam um coproduto de qualidade a ser aproveitado pela indústria. Além de contribuir para para fornecer dados, junto a outros trabalhos, para se criar um padrão de identidade e qualidade da CMS de pescado, o que é de suma importância para o controle de qualidade da indústria processadora do coproduto. / The use of fish protein resulting from the industrial process constitutes an alternative to the development of co-products with nutritional quality. Mechanically recovered meat (MRM), produced from carcasses of Red hybrid tilapia, Oreochromis niloticus var. Red Stirling and black tilapia Oreochromis niloticus were characterized in terms of physical, chemical, microbiological and sensory aspects. The first study evaluated the efficiency of two mechanical extraction devices of MRM, the screw type and the belt and drum type. Later assessed the quality of frozen MRM for 90 days of storage. Then it was evaluated the sensory attributes of color, odor and appearance of defrozen MRM. The resulting MRM was used in the development of a tomato sauce and its acceptance with consumers was analyzed. A performance study of MRM restructured of red hybrid tilapia was conducted. The worm screw-type separator presented better extraction yield when compared to belt-drum type separator, but both processes allowed obtaining MRM with levels of moisture, protein and lipids suitable for processing co-products. Both MRM presented microbiological and oxidative stability after 90 days of storage. The sensory analysis of control difference for up to 90 days showed significant difference to that at 15 days of storage. The team of tasters set the value 4 (appearance, color and odor moderately different from the control) as limiting MRM shelf life to 60 days for MRM of the Nile tilapia and 90 days for MRM of the red tilapia. The tomato sauce with the addition of tilapia formulated with MRM of the red tilapia stored for 15 and 90 days was well accepted by consumers, but purchase intent dropped 19% for the product obtained from MRM with 90 days of storage. The MRM from the red hybrid tilapia is a raw material with high protein content, average 12%, and high lipid content, average 15%, and can be used to prepare different co-products of tilapia. It was possible to obtain restructured product with addition of 100% of MRM from the red hybrid tilapia with good processing characteristics, which shows viability of production with satisfactory responses of performance, water retention capacity and penetration force of restructured fish meat. We conclude that the CMS of the studied tilapia varieties represent a quality co-product to be used by the industry. Besides contributing to to provide data , along with other works , to create a standard of identity and quality of fish CMS , which is of paramount importance for the quality control of the co-product processing industry.

The objectives of the research were to examine the effects of high dietary levels of fibrous feeds, and of supplementation with Roxazyme® G2 (RX), on the digestive metabolic and physiological responses of growing pigs fed maize-soybean diets. The nutrient and dietary fibre (DF) composition, the swelling and water-binding capacities of maize (MM), its hominy chop (HC) and cobs (MC), dehulled soybean (dSBM) and the hulls (SH), brewer’s grains (BG), lucerne hay (LH) and wheat bran (WB) were evaluated using standard procedures. Feed fibre fractions were isolated by simulating upper tract digestion in an Ankom® DaisyII Incubator, whereby each feed was digested in pepsin (porcine, 200 FIP-U/g, Merck No, 7190), followed by pancreatin (porcine, grade IV, Sigma No P-1750), with recovery of the fibrous residues. In a third step to complete the simulated pig gastro-intestinal digestion, the pepsin-pancreatin fibre extracts were digested by RX or Viscozyme L ® V2010 (VZ). Enzyme activity was measured as the coefficients of partial degradability (solubilisation) of the washed fibre extracts. The kinetics and products of fermentation of the DF were evaluated in an AnkomRF gas production system, using buffered faecal inoculum. Among the feed ingredients, dissimilar, fibre source-dependent activities between RX (0.02 to 0.12) and VZ (0.04-0.33) were observed. The lowest RX activities were observed on the maize and soybean derived fibres, with similarly low VZ activity on MC fibre. Variation in the activity of faecal microbial enzymes was similarly indicated by the variable production of fermentation gas (51.8-299.4 mL g-1 DM) and short chain fatty acids (SCFA) (2.3-6.0 mMol g-1 DM). Soy hull, dSBH, MM and HC fibres were highly fermentable, with low fermentability of BG, MC and WB fibres. The fibres differed in the composition of fermentation SCFA, whereby SH, LH and MC shifted fermentation to Ace, and BG, dSBM, WB, MM, HC favoured Pro, while MM and HC favoured But production. The same nutritional properties were similarly evaluated in complete diets which were formulated from the ingredients for growth, and metabolic trials. For the growth trial, a standard (STD) (control), 141 g total dietary fibre (TDF) kg-1 dry matter (DM) maize-soybean growing pig diet, and five iso-nutritive, 246 g TDF kg-1 DM nutritionally balanced diets were formulated. The high DF was achieved by partial replacement of the MM and dSBM in the STD diet with MC, SH, BG, LH or WB. The differences in RX and VZ activities and in the fermentation characteristics which were observed on the fibre extracts from the high fibre ingredients were reflected in the DF from the respective complete diets in which they were included. However, the fibre from the basal dietary ingredients reduced the absolute values and the variation in the activities of RX (0.03-0.06) and VZ (0.16-0.22), and similarly reduced the variation in gas (126.6-187.6 mL g-1 DM) and SCFA (4.1-5.4 mMol g-1 DM) production of the DF from the fibrous diets. Enzyme activities on the STD DF were low for RX (0.03) and high for VZ (0.25). The STD DF produced 205.3 mL gas g-1 DM, which was similar to SH DF, and higher than all the other diets. The STD DF produced 5.0-mMol SCFA g-1 DM, which was quantitatively, and not statistically higher than the other fibres. The composition of SCFA was similar across all diets, except for the high percent Ace, with low Pro by the SH DF. Compared to the STD, the high DF diets increased percent Ace, with reduced Pro and But. The STD, MC, SH, BG, LH and WB diets were each prepared in duplicate mixes, one of which was fortified with 200 mg RX kg-1 feed (as fed). Seventy-two intact Large White X Landrace, male, 32.0 ± 5.6 kg live weight (LW) pigs were allocated to the diets in two completely randomised weight blocks in a 2 (fibre source) X 2 (enzyme) factorial arrangement. The pigs were fed ad libitum for 10 weeks. Cumulative LW gain and feed intake were measured at different stages of growth, and at slaughter. Apparent total tract digestibility (ATTD) of nutrients was estimated at 65-70 kg LW, using 0.2% (as fed) chromium oxide as the indigestible marker. Ileal tissue was sampled 50 cm above the ileo-caecal valve, on which villi height and area, and crypt depth were evaluated by computerised image analysis. Blood was sampled at slaughter from the severed vena jugularis, 16 hours after feeding. Serum urea, creatinine, triglycerides, glucose, and total cholesterol were analysed chemically. The serum metabolome was further explored using Proton Nuclear Magnetic Resonance Spectroscopy (1H -NMRS). There was fibre X RX interaction for villi height, whereby the enzyme reduced the villi height in pigs on the SH, STD and WB diets, with an opposite effect on pigs on the MC, BG, LH diets. The soluble fibre content was negatively correlated with crypt depth. Chemical analysis did not detect differences in metabolite concentration between the STD and the high fibre diets. However, more serum cholesterol was observed in pigs fed the WB compared to the LH and MC diets. 1H-NMRS indicated that feeding pigs the WB diet increased serum Cys and His, while supplementation of RX increased serum formate, glucose, and urea. There was diet X enzyme interaction for fructose, glucose, Arg, Cys, Ser, and Trp, whereby RX increased the levels in pigs on MC and WB, with an opposite effect in pigs on the other diets. There was large DF source-dependent variation among diets in ATTD of DM (0.80-0.85), organic matter (OM) (0.81-0.87), gross energy (GE) (079-0.85) and CP (0.81-0.85), whereby, relative to the STD diet, high DF reduced the ATTD of DM (all diets except SH), organic matter (OM) and energy and CP (all diets except the MC). Positive correlation was observed between fermentability and the ATTD digestibility of DM, OM, energy, ADF, NDF, and fat. Negative correlation was observed between the swelling capacity and the ATTD of DM, OM, energy and protein, between DF solubility and DM, OM, protein, ADF and NDF, and between water binding capacity and ATTD of DM and OM, energy and NDF. At slaughter, there was similarly large, and DF source-dependent variation among the high fibre diets in feed intake (2.31-2.71 kg as fed day-1), live weight gain (0.75-0.86 kg day-1), and feed: gain ratio (2.73-3.00). Corresponding values for the STD diet were 2.44 kg day-1, 0.83 kg day-1and 2.86 kg day-1, respectively. Relative to the STD, LH reduced feed intake and live weight gain, and MC increased the feed: gain ratio. Predictions based on the in vitro fermentability of DF and feed intake suggested that due to poor fermentability, and or restriction of feed intake, relative to a standard fibre diet, high dietary levels of MC, WB and BG may reduce fermentation in the lower gut, while similar dietary levels of SH and LH may result in substantial increases in fermentation. At 50 kg LW, the fermentability of DF was positively correlated with feed intake and with weight gain, while water binding capacity and solubility of DF were negatively correlated with feed intake. At slaughter, the solubility of DF was negatively correlated with feed intake and feed: gain ratio. Large variation among the high fibre diets was also observed in the slaughter weight (89.2-96.8 kg), dressing % (68.6-76.4), meat colour (80.4-82.3), lean % (69.5-71.2), and fat % (10.1-12.6). In comparison, pigs on the STD diet scored 94.7 kg slaughter weight, 75.1% dressing, 81.6 cm carcass length, 82.5 meat colour, 68.4% lean, and 15.0% fat. Relative to the STD, LH reduced dressing and fat %. Lucerne hay and WB increased the lean%. For the metabolic trial, two iso-nutritive, mixed high fibre (319 g TDF kg-1 DM), nutritionally balanced diets were formulated to contain DF of high (HF) versus low (LF) fermentability. The diets had similar content of soluble DF and similar swelling and water binding capacities. Viscozyme was more active than RX on both the HF (0.20 versus 0.04) and the LF (0.17 versus 0.07) DF. The combination of RX and VZ statistically increased the enzyme activity on the HF (0.25) and quantitatively increased enzyme activity on the LF (0.18) DF, suggesting additive or synergistic effects. More gas was produced by the HF (159.5 mL g-1 DM) compared to the LF DF (96.6 mL g-1 DM). More SCFA were produced by HF (5.0 mMol g-1 DM), compared to the LF DF (3.6 mMol g-1 DM). Compared to the STD, HF DF increased percent Ace, with reduced Pro and But. The LF DF increased percent Ace, with quantitative, and not statistical reduction of Pro and But. In a metabolic trial, the HF and LF diets, and their duplicates containing 0.270 g RX kg-1 DM of feed (as fed) were fed ad libitum to eight ileum T-cannulised, intact Large White X Landrace male pigs weighing 65.0 ± 5.1 kg. The diets were allocated to the pigs in a duplicate 4 x 4 Latin Square design, in a 2 (enzyme) x 2 (fermentability) factorial arrangement. Each period consisted of two weeks of adaptation followed by five days of sampling. The ileal digesta was collected in each period and was similarly subjected to the fermentation test. Apparent ileal digestibility (AID) and ATTD were determined using 0.2% (as fed) chromium oxide as the indigestible marker. N excretion in faeces and urine were measured, and N retention was calculated. Blood was sampled by vena jugularis puncture on the last day of each period. Two blood samples were collected, the first 15 hours after removal from feed (15-hour serum), and the second 3 hours after re-introduction to feed (3-hour serum). Serum metabolites were evaluated by both chemical analyses and by 1H-NMRS, as described for the growth trial. Roxazyme did not affect the fermentation characteristics of the ileal digesta. In similar proportion to the fermentability of the PP digesta, the HF ileal digesta was more fermentable (65.4 mL gas g-1 DM and 6.1 mMol SCFA g-1 DM) than the LF ileal digesta (46.7 mL gas g-1 DM and 4.4 mMol SCFA g-1 DM SCFA). Prediction based on the in vitro fermentability of DF and feed intake suggested the HF diet could support one half times more fermentation in the lower gut compared to the LF diet. The HF diet had higher AID of DM (62.5 vs. 58.6), OM (65.6 vs. 62.1), energy (64.4 vs. 61.0), fat (85.8 vs. 81.7) and ash (41.8 vs. 32.7). The AID of HO-Pro, Met and Val were higher for the LF diet. There was diet X enzyme interaction on the AID of Met, whereby the RX reduced the AID of met in the LF diet, and not that of the HF diet. The ATTD was higher for the HF diet for DM (74.2 vs. 68.4), NDF (64.7 vs. 57.4), and ADF (35.1 vs. 21.0). There was positive correlation between the fermentability of DF and the AID DM, OM, ash, ash, fat and energy. The solubility of DF was negatively correlated with the AID of DM, OM, ash, fat, ADF and energy, and with the ATTD of DM, OM, ash, fat, energy, NDF, and ADF. Negative correlation was also observed between the swelling capacity of DF and the AID of protein, Trp and Lys. The solubility of DF was positively correlated with Ser, Ala, Val, Iso-Leu and His. There was diet X enzyme interaction for urea in the 15- hour serum, whereby RX tended to reduce the urea in the LF diet, while it increased that of the HF diet. Fermentability negatively correlated with urea in the 15- hour serum, and positively correlated with serum glucose in the 3-hour serum. In the 3-hour sample, 1H-NMRS indicated higher fucose, Pro and cholesterol in the LF diet. 1H-NMRS also indicated fermentability x RX interaction for Ser, Tyr, Lys, creatine, and possibly, glucose or fructose, glycerol or Gly and His or Arg, whereby RX increased the levels in the LF diets, with opposite effect in the HF diet. In conclusion, enzyme activities and fermentability were higly variable among different DF sources, and the effects were evident in the fibrous complete diets. The results of the in vitro studies supported the application of the methods to formulate fermentable insoluble fibre-rich, maize-soybean-mixed co-product diets. Correlation analyses suggested that DF fermentability, and solubility, swelling and water binding capacities explained significant proportions of the variances of the metabolic and physiological responses of the pigs to different feeds. Predictions based on the in vitro fermentability of DF and feed intake suggested that a strategy whereby pig diets are enriched in DF after the feedstuffs are screened on DF fermentability could substantially increase fermentation in the lower gut. Overall, the results suggested that productivity can be maintained in growing pigs fed diets containing up to twice the standard levels of DF, provided producers target co-product feeds that contain highly fermentable DF. The use of RX to improve nutrient digestion and to stimulate gut fermentation was not justified. / Environmental Sciences / Ph.D. (Environmental Sciences)

The objectives of the research were to examine the effects of high dietary levels of fibrous feeds, and of supplementation with Roxazyme® G2 (RX), on the digestive metabolic and physiological responses of growing pigs fed maize-soybean diets. The nutrient and dietary fibre (DF) composition, the swelling and water-binding capacities of maize (MM), its hominy chop (HC) and cobs (MC), dehulled soybean (dSBM) and the hulls (SH), brewer’s grains (BG), lucerne hay (LH) and wheat bran (WB) were evaluated using standard procedures. Feed fibre fractions were isolated by simulating upper tract digestion in an Ankom® DaisyII Incubator, whereby each feed was digested in pepsin (porcine, 200 FIP-U/g, Merck No, 7190), followed by pancreatin (porcine, grade IV, Sigma No P-1750), with recovery of the fibrous residues. In a third step to complete the simulated pig gastro-intestinal digestion, the pepsin-pancreatin fibre extracts were digested by RX or Viscozyme L ® V2010 (VZ). Enzyme activity was measured as the coefficients of partial degradability (solubilisation) of the washed fibre extracts. The kinetics and products of fermentation of the DF were evaluated in an AnkomRF gas production system, using buffered faecal inoculum. Among the feed ingredients, dissimilar, fibre source-dependent activities between RX (0.02 to 0.12) and VZ (0.04-0.33) were observed. The lowest RX activities were observed on the maize and soybean derived fibres, with similarly low VZ activity on MC fibre. Variation in the activity of faecal microbial enzymes was similarly indicated by the variable production of fermentation gas (51.8-299.4 mL g-1 DM) and short chain fatty acids (SCFA) (2.3-6.0 mMol g-1 DM). Soy hull, dSBH, MM and HC fibres were highly fermentable, with low fermentability of BG, MC and WB fibres. The fibres differed in the composition of fermentation SCFA, whereby SH, LH and MC shifted fermentation to Ace, and BG, dSBM, WB, MM, HC favoured Pro, while MM and HC favoured But production. The same nutritional properties were similarly evaluated in complete diets which were formulated from the ingredients for growth, and metabolic trials. For the growth trial, a standard (STD) (control), 141 g total dietary fibre (TDF) kg-1 dry matter (DM) maize-soybean growing pig diet, and five iso-nutritive, 246 g TDF kg-1 DM nutritionally balanced diets were formulated. The high DF was achieved by partial replacement of the MM and dSBM in the STD diet with MC, SH, BG, LH or WB. The differences in RX and VZ activities and in the fermentation characteristics which were observed on the fibre extracts from the high fibre ingredients were reflected in the DF from the respective complete diets in which they were included. However, the fibre from the basal dietary ingredients reduced the absolute values and the variation in the activities of RX (0.03-0.06) and VZ (0.16-0.22), and similarly reduced the variation in gas (126.6-187.6 mL g-1 DM) and SCFA (4.1-5.4 mMol g-1 DM) production of the DF from the fibrous diets. Enzyme activities on the STD DF were low for RX (0.03) and high for VZ (0.25). The STD DF produced 205.3 mL gas g-1 DM, which was similar to SH DF, and higher than all the other diets. The STD DF produced 5.0-mMol SCFA g-1 DM, which was quantitatively, and not statistically higher than the other fibres. The composition of SCFA was similar across all diets, except for the high percent Ace, with low Pro by the SH DF. Compared to the STD, the high DF diets increased percent Ace, with reduced Pro and But. The STD, MC, SH, BG, LH and WB diets were each prepared in duplicate mixes, one of which was fortified with 200 mg RX kg-1 feed (as fed). Seventy-two intact Large White X Landrace, male, 32.0 ± 5.6 kg live weight (LW) pigs were allocated to the diets in two completely randomised weight blocks in a 2 (fibre source) X 2 (enzyme) factorial arrangement. The pigs were fed ad libitum for 10 weeks. Cumulative LW gain and feed intake were measured at different stages of growth, and at slaughter. Apparent total tract digestibility (ATTD) of nutrients was estimated at 65-70 kg LW, using 0.2% (as fed) chromium oxide as the indigestible marker. Ileal tissue was sampled 50 cm above the ileo-caecal valve, on which villi height and area, and crypt depth were evaluated by computerised image analysis. Blood was sampled at slaughter from the severed vena jugularis, 16 hours after feeding. Serum urea, creatinine, triglycerides, glucose, and total cholesterol were analysed chemically. The serum metabolome was further explored using Proton Nuclear Magnetic Resonance Spectroscopy (1H -NMRS). There was fibre X RX interaction for villi height, whereby the enzyme reduced the villi height in pigs on the SH, STD and WB diets, with an opposite effect on pigs on the MC, BG, LH diets. The soluble fibre content was negatively correlated with crypt depth. Chemical analysis did not detect differences in metabolite concentration between the STD and the high fibre diets. However, more serum cholesterol was observed in pigs fed the WB compared to the LH and MC diets. 1H-NMRS indicated that feeding pigs the WB diet increased serum Cys and His, while supplementation of RX increased serum formate, glucose, and urea. There was diet X enzyme interaction for fructose, glucose, Arg, Cys, Ser, and Trp, whereby RX increased the levels in pigs on MC and WB, with an opposite effect in pigs on the other diets. There was large DF source-dependent variation among diets in ATTD of DM (0.80-0.85), organic matter (OM) (0.81-0.87), gross energy (GE) (079-0.85) and CP (0.81-0.85), whereby, relative to the STD diet, high DF reduced the ATTD of DM (all diets except SH), organic matter (OM) and energy and CP (all diets except the MC). Positive correlation was observed between fermentability and the ATTD digestibility of DM, OM, energy, ADF, NDF, and fat. Negative correlation was observed between the swelling capacity and the ATTD of DM, OM, energy and protein, between DF solubility and DM, OM, protein, ADF and NDF, and between water binding capacity and ATTD of DM and OM, energy and NDF. At slaughter, there was similarly large, and DF source-dependent variation among the high fibre diets in feed intake (2.31-2.71 kg as fed day-1), live weight gain (0.75-0.86 kg day-1), and feed: gain ratio (2.73-3.00). Corresponding values for the STD diet were 2.44 kg day-1, 0.83 kg day-1and 2.86 kg day-1, respectively. Relative to the STD, LH reduced feed intake and live weight gain, and MC increased the feed: gain ratio. Predictions based on the in vitro fermentability of DF and feed intake suggested that due to poor fermentability, and or restriction of feed intake, relative to a standard fibre diet, high dietary levels of MC, WB and BG may reduce fermentation in the lower gut, while similar dietary levels of SH and LH may result in substantial increases in fermentation. At 50 kg LW, the fermentability of DF was positively correlated with feed intake and with weight gain, while water binding capacity and solubility of DF were negatively correlated with feed intake. At slaughter, the solubility of DF was negatively correlated with feed intake and feed: gain ratio. Large variation among the high fibre diets was also observed in the slaughter weight (89.2-96.8 kg), dressing % (68.6-76.4), meat colour (80.4-82.3), lean % (69.5-71.2), and fat % (10.1-12.6). In comparison, pigs on the STD diet scored 94.7 kg slaughter weight, 75.1% dressing, 81.6 cm carcass length, 82.5 meat colour, 68.4% lean, and 15.0% fat. Relative to the STD, LH reduced dressing and fat %. Lucerne hay and WB increased the lean%. For the metabolic trial, two iso-nutritive, mixed high fibre (319 g TDF kg-1 DM), nutritionally balanced diets were formulated to contain DF of high (HF) versus low (LF) fermentability. The diets had similar content of soluble DF and similar swelling and water binding capacities. Viscozyme was more active than RX on both the HF (0.20 versus 0.04) and the LF (0.17 versus 0.07) DF. The combination of RX and VZ statistically increased the enzyme activity on the HF (0.25) and quantitatively increased enzyme activity on the LF (0.18) DF, suggesting additive or synergistic effects. More gas was produced by the HF (159.5 mL g-1 DM) compared to the LF DF (96.6 mL g-1 DM). More SCFA were produced by HF (5.0 mMol g-1 DM), compared to the LF DF (3.6 mMol g-1 DM). Compared to the STD, HF DF increased percent Ace, with reduced Pro and But. The LF DF increased percent Ace, with quantitative, and not statistical reduction of Pro and But. In a metabolic trial, the HF and LF diets, and their duplicates containing 0.270 g RX kg-1 DM of feed (as fed) were fed ad libitum to eight ileum T-cannulised, intact Large White X Landrace male pigs weighing 65.0 ± 5.1 kg. The diets were allocated to the pigs in a duplicate 4 x 4 Latin Square design, in a 2 (enzyme) x 2 (fermentability) factorial arrangement. Each period consisted of two weeks of adaptation followed by five days of sampling. The ileal digesta was collected in each period and was similarly subjected to the fermentation test. Apparent ileal digestibility (AID) and ATTD were determined using 0.2% (as fed) chromium oxide as the indigestible marker. N excretion in faeces and urine were measured, and N retention was calculated. Blood was sampled by vena jugularis puncture on the last day of each period. Two blood samples were collected, the first 15 hours after removal from feed (15-hour serum), and the second 3 hours after re-introduction to feed (3-hour serum). Serum metabolites were evaluated by both chemical analyses and by 1H-NMRS, as described for the growth trial. Roxazyme did not affect the fermentation characteristics of the ileal digesta. In similar proportion to the fermentability of the PP digesta, the HF ileal digesta was more fermentable (65.4 mL gas g-1 DM and 6.1 mMol SCFA g-1 DM) than the LF ileal digesta (46.7 mL gas g-1 DM and 4.4 mMol SCFA g-1 DM SCFA). Prediction based on the in vitro fermentability of DF and feed intake suggested the HF diet could support one half times more fermentation in the lower gut compared to the LF diet. The HF diet had higher AID of DM (62.5 vs. 58.6), OM (65.6 vs. 62.1), energy (64.4 vs. 61.0), fat (85.8 vs. 81.7) and ash (41.8 vs. 32.7). The AID of HO-Pro, Met and Val were higher for the LF diet. There was diet X enzyme interaction on the AID of Met, whereby the RX reduced the AID of met in the LF diet, and not that of the HF diet. The ATTD was higher for the HF diet for DM (74.2 vs. 68.4), NDF (64.7 vs. 57.4), and ADF (35.1 vs. 21.0). There was positive correlation between the fermentability of DF and the AID DM, OM, ash, ash, fat and energy. The solubility of DF was negatively correlated with the AID of DM, OM, ash, fat, ADF and energy, and with the ATTD of DM, OM, ash, fat, energy, NDF, and ADF. Negative correlation was also observed between the swelling capacity of DF and the AID of protein, Trp and Lys. The solubility of DF was positively correlated with Ser, Ala, Val, Iso-Leu and His. There was diet X enzyme interaction for urea in the 15- hour serum, whereby RX tended to reduce the urea in the LF diet, while it increased that of the HF diet. Fermentability negatively correlated with urea in the 15- hour serum, and positively correlated with serum glucose in the 3-hour serum. In the 3-hour sample, 1H-NMRS indicated higher fucose, Pro and cholesterol in the LF diet. 1H-NMRS also indicated fermentability x RX interaction for Ser, Tyr, Lys, creatine, and possibly, glucose or fructose, glycerol or Gly and His or Arg, whereby RX increased the levels in the LF diets, with opposite effect in the HF diet. In conclusion, enzyme activities and fermentability were higly variable among different DF sources, and the effects were evident in the fibrous complete diets. The results of the in vitro studies supported the application of the methods to formulate fermentable insoluble fibre-rich, maize-soybean-mixed co-product diets. Correlation analyses suggested that DF fermentability, and solubility, swelling and water binding capacities explained significant proportions of the variances of the metabolic and physiological responses of the pigs to different feeds. Predictions based on the in vitro fermentability of DF and feed intake suggested that a strategy whereby pig diets are enriched in DF after the feedstuffs are screened on DF fermentability could substantially increase fermentation in the lower gut. Overall, the results suggested that productivity can be maintained in growing pigs fed diets containing up to twice the standard levels of DF, provided producers target co-product feeds that contain highly fermentable DF. The use of RX to improve nutrient digestion and to stimulate gut fermentation was not justified. / Environmental Sciences / Ph.D. (Environmental Sciences)

Submitted by LILIAN FACHIN LEONARDO BETIOL null (lilianfacleo@hotmail.com) on 2016-12-04T18:12:23Z No. of bitstreams: 1 Tese - Formatada (1) Corrigida.pdf: 1975637 bytes, checksum: a2ca74a2f726452b217e860e0c11c866 (MD5) / Approved for entry into archive by Felipe Augusto Arakaki (arakaki@reitoria.unesp.br) on 2016-12-06T13:52:01Z (GMT) No. of bitstreams: 1 betiol_lfl_me_sjrp.pdf: 1975637 bytes, checksum: a2ca74a2f726452b217e860e0c11c866 (MD5) / Made available in DSpace on 2016-12-06T13:52:01Z (GMT). No. of bitstreams: 1 betiol_lfl_me_sjrp.pdf: 1975637 bytes, checksum: a2ca74a2f726452b217e860e0c11c866 (MD5) Previous issue date: 2016-11-21 / As isotermas de sorção tornaram-se importantes para prever o comportamento da cinética de secagem e as condições de armazenamento de resíduos da indústria alimentícia. O conhecimento de tal propriedade é útil para projetar equipamentos ou operações para fins de armazenamento ou processamento. O bagaço quando é apenas descartado, representa um desperdício de matéria prima, de compostos orgânicos com categoria bioquímica definida (proteínas, açúcares, ceras, graxas, resinas), que poderia ser aproveitada. Dentro deste contexto, a presente pesquisa teve como objetivo caracterizar quimicamente o bagaço de mandioca e fazer a determinação experimental das isotermas de sorção destes resíduos da indústria de fécula, além de calcular a entalpia e entropia, temperatura media harmônica e calor isostérico de adsorção. Para isso, o teor de umidade de equilíbrio nas isotermas de sorção, de bagaço de mandioca, foi determinado utilizando o método gravimétrico estático nas temperaturas de 20 a 80 °C. Modelos teóricos e empíricos foram usados para representar os valores experimentais das isotermas de sorção, sendo que o modelo de GAB foi o que apresentou os melhores ajustes. Utilizando o modelo de GAB foi possível determinar o calor isostérico de adsorção como função do teor de umidade. A teoria da compensação foi confirmada pela relação linear entre entalpia e entropia. Maiores valores de temperatura isocinética do que a temperatura harmônica reforçam a teoria da compensação e sugeriram que a adsorção de água pelo bagaço de mandioca é considerado um processo conduzido pela entalpia. / The sorption isotherms become important to predict the drying kinetics behavior and waste storage conditions of the food industry. The knowledge of such property is useful for designing equipment or operations for storage or processing. The bagasse is only when discarded, is a waste of raw materials, organic compounds with defined biochemical category (proteins, sugars, waxes, greases, resins), which could be harnessed. Within this context, this study aimed to chemically characterize the Cassava Bagasse and make the experimental determination of the sorption isotherms of these starch industry waste and calculates the enthalpy and entropy, harmonic average temperature and isosteric heat of adsorption. For this, the equilibrium moisture content in the sorption isotherms of cassava bagasse was determined using the gravimetric static method in temperatures 20-80 ° C. Theoretical and empirical models were used to represent the experimental values of sorption isotherms, and the GAB model was the one that presented the best fit. Using the GAB model was possible to determine the isosteric heat of adsorption and moisture content of the function. The theory of compensation was confirmed by the linear relationship between enthalpy and entropy. Isokinetic higher temperature values than the harmonic temperature reinforce the theory of compensation and suggested that the adsorption of water by mancioca bagasse and considered one of enthalpy driven process.

Submitted by Jaqueline Silva (jtas29@gmail.com) on 2014-12-12T19:44:10Z No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Tese-Pedro Leonardo de Paula Rezende-2013.pdf: 1990022 bytes, checksum: 4763bbae50ef3499c69013720dde8eb1 (MD5) / Approved for entry into archive by Jaqueline Silva (jtas29@gmail.com) on 2014-12-16T09:26:17Z (GMT) No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Tese-Pedro Leonardo de Paula Rezende-2013.pdf: 1990022 bytes, checksum: 4763bbae50ef3499c69013720dde8eb1 (MD5) / Made available in DSpace on 2014-12-16T09:26:17Z (GMT). No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Tese-Pedro Leonardo de Paula Rezende-2013.pdf: 1990022 bytes, checksum: 4763bbae50ef3499c69013720dde8eb1 (MD5) Previous issue date: 2013-12-16 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / We studied the effect of substitution of 0, 33, 66 and 100% of ground corn (GC) by soybean hulls (SH) in diet’s concentrate portion of 144 Nellore heifers of 24 to 30 months of age and 263.40 + 13.90 kg of body weight in beginning of feedlot and slaughtered at different weights (<340, 340-370, 370-400 and >400 kg). There was no significant interaction between levels of substitution of GC by SH and slaughter weight classes being these effects studied separately. Diets were composed of 90 % concentrate and 10 % corn silage. The experimental period was 112 days, including the period of adaptation. The dry matter intake was not altered by substitution of GC by SH with mean values of 2.51 % of body weight. The substitution level of GC by SH resulted in a linear increase in NDF intake (1.08, 2.03, 2.92 and 3.78 kg/day) and reduced consumption of NDT (5.78, 5 16, 5.03 and 5.12 kg/day) with the addition of 0, 33, 66 and 100 % of GC by SH substitution, respectively. The average daily weight gain decreased linearly (1.24, 1.11, 1.02 and 0.89 kg / day), while feed conversion increased (6.20, 7.08, 7.77 and 8.67 kg DM intake/kg ADG) for the levels of 0, 33, 66 and 100% SH in the diet, respectively. The body condition score was not influenced by levels of substitution of GC by SH presenting mean values of 3.51 points. The body measurements were not affected by treatments, both on the back as the withers, with mean values of 138.5 and 133.25 cm, respectively. Measures of thorax perimeter and body length decreased linearly with the inclusion of SH levels. The slaughter weight decreased linearly with values of 383.52, 374.71, 363.25 and 366.27 kg for levels of 0, 33, 66 and 100 % replacement of GC for SH, respectively, however the hot carcass weight or cold were not affected by the replacement of GC by SH and showed average values of 203.52 and 199.25 kg, respectively. There was no effect of dietary treatment on hot carcass yield showing mean values of 54.92 %. The conformation of the carcasses was not affected by the replacement of GC by SH, with average values of 9.16 points. The subcutaneous fat thickness and loin eye area were not affected by dietary treatments and showed mean values of 5.3 mm and 53.08 cm2, respectively. The yields of primary carcass cut (front, special needle and side cut) were not affected by SH inclusion levels and showed average values of 36.52, 51.72 and 11.55%, respectively. The objective measurements of carcass were not affected by replacement levels of GC by SH. It was found linear effect of treatments on the compactness of carcasses showing average values of 1.56, 1.57, 1.51 and 1.45 cm/kg of cold carcass, to replacing levels of 0, 33, 66 and 100% of SH, respectively. The color and texture of meat were not influenced by dietary treatments and showed average values of 3.30 and 3.19 points, respectively. The marbling of the meat was not influenced by the substitution of GC by SH presenting mean values 8.56 points, with amplitude values between 2 and 17 points. The elevation of slaughter weight resulted in increased weights of hot and cold carcass. Animals slaughtered with weight >400kg had hot carcass yield of 52.76 %, lower than the group of 370-400 kg (56.55 %). The subcutaneous fat thickness was not affected by slaughter weight in any of the expression forms of this variable, with mean values of 5.26 mm and 2.67% of the cold carcass weight. The loin eye area increased with the increase of slaughter weight, and the correlation between these variables was 0.62 (P=0.001), however, when this variable was expressed to 100 kg cold carcass this difference disappeared, with average scores of 26,72 cm2 for each 100 kg of cold carcass. The animals slaughtered with weight >400kg showed better conformation (9.79 points) compared to the other weight classes did not differ among themselves. There was a significant effect of slaughter weight on the carcasses length, arm perimeter and cushion thickness which increased 5.9, 2.3 and 3.12 cm, respectively, amounted to slaughter weight of <340 to >400 kg. Animals slaughtered with weight >400kg had higher carcass compactness compared to the other treatments (1.65 cm long/ kg of cold carcass weight). The absolute weights of primary cuts of the carcass increased with the slaughter weight, however to adjust the weights of the front and rear to 100 kg of cold carcass, this difference disappeared, with values of 36.59 and 51.99%, respectively. The color and texture of the meat were not influenced by slaughter weights showing average values of 3.28 and 3.19 points, respectively. The marbling of the meat was lower in the group of animals slaughtered weighing less than 340 kg compared to the other weight classes did not differ among themselves. It was concluded which although not influence the main carcass characteristics, the replace of ground corn by soybean hulls in high concentrate diets is not efficient because has depressing effect on the productive performance, notably weight gain and feed conversion. Feedlot Nellore heifers must not be slaughtered weighing less than 340 kg because they have lower carcass weight and less marbling of the meat. / Foram estudados os efeitos da substituição de 0, 33, 66 e 100% do milho moído (MM) por casca do grão de soja (CS), na porção concentrada da dieta, de 144 novilhas de descarte da raça Nelore com 24 a 30 meses de idade e 263,40 + 13,90 kg de peso vivo médio inicial, terminadas em confinamento e abatidas com diferentes pesos (<340; 340-370; 370-400 e >400 kg). Não foi constatada interação significativa entre os níveis de substituição do MM pela CS e classes de peso ao abate sendo estes efeitos estudados separadamente. As dietas foram constituídas de 90% de concentrado e 10% de silagem de milho. O período experimental foi de 112 dias, incluindo o período de adaptação. O consumo de matéria seca não foi alterado pelos níveis de CS na dieta com valores médios de 2,51% do peso corporal. A elevação do nível de CS em substituição ao MM resultou em aumento linear do consumo de FDN (1,08; 2,03; 2,92 e 3,78 kg/dia) e redução do consumo de NDT (5,78; 5,16; 5,03 e 5,12 kg/dia) com a inclusão de 0, 33, 66 e 100% de CS em substituição ao MM, respectivamente. O ganho de peso médio diário reduziu linearmente (1,24; 1,11; 1,02 e 0,89 kg/dia), enquanto a conversão alimentar aumentou (6,20; 7,08; 7,77 e 8,67 kg de MS ingerida/kg de GMD) para os níveis de 0, 33, 66 e 100% de CS na dieta, respectivamente. O escore de condição corporal não foi alterado pelos níveis de substituição do MM por CS apresentando valores médios de 3,51 pontos. As medidas corporais de altura não foram influenciadas pelos tratamentos, tanto na garupa quanto na cernelha, apresentando valores médios de 138,5 e 133,25 cm, respectivamente. As medidas de perímetro torácico e comprimento corporal reduziram linearmente, conforme aumentou a inclusão de CS. O peso de abate (PAB) reduziu linearmente apresentando valores de 383,52; 374,71; 363,25 e 366,27 kg para os níveis de 0, 33, 66 e 100% de substituição do MM por CS, respectivamente, entretanto os pesos de carcaça quente (PCQ) ou fria (PCF) não foram alterados pela substituição do MM por CS e apresentaram valores médios de 203,52 e 199,25 kg, respectivamente. Não foi constatado efeito dos tratamentos alimentares sobre o rendimento de carcaça quente que apresentou valores médios de 54,92%. A conformação das carcaças não foi influenciada pela substituição do MM por CS, apresentando valores médios de 9,16 pontos. A espessura de gordura subcutânea (EGS) e a área de olho de lombo (AOL) não foram influenciadas pelos tratamentos alimentares e apresentaram valores médios de 5,3 mm e 53,08 cm2, respectivamente. O rendimento dos cortes primários da carcaça dianteiro, traseiro especial e ponta de agulha não foram alterados pela inclusão de CS e apresentaram valores médios de 36,52; 51,72 e 11,55% da carcaça fria, respectivamente. As medidas objetivas da carcaça não foram influenciadas pelos níveis de substituição do MM por CS. Constatou-se efeito linear decrescente dos tratamentos sobre a compacidade das carcaças apresentando valores médios de 1,56; 1,57; 1,51e 1,45 cm/kg de carcaça fria, para os níveis de 0, 33, 66 e 100% de substituição do MM por CS, respectivamente. A cor e a textura da carne não foram influenciadas pelos tratamentos alimentares e apresentaram valores médios de 3,30 e 3,19 pontos, respectivamente. O marmoreio da carne não foi alterado pela substituição do MM por CS apresentando valores médios 8,56 pontos, com valores de amplitude entre 2 e 17 pontos. A elevação dos pesos de abate resultou em aumento dos pesos da carcaça quente e fria. Animais abatidos com peso superior à 400 kg apresentaram rendimento de carcaça quente de 52,76%, inferior ao grupo de 370-400 kg (56,55%). A EGS não foi influenciada pelos pesos de abate em nenhuma das formas de expressão desta variável, apresentando valores médios de 5,26 mm e 2,67% em relação ao peso da carcaça fria. A AOL aumentou com a elevação dos pesos de abate, sendo a correlação entre estas variáveis de 0,62 (P=0,001) entretanto quando esta variável foi ajustada para 100 kg de carcaça fria esta diferença deixou de existir, apresentando resultados médios de 26,72 cm2 para cada 100 kg de carcaça fria. Os animais abatidos com peso superior a 400 kg apresentaram melhor conformação (9,79 pontos) que os demais grupos experimentais que não diferiram entre si. Verificou-se efeito significativo dos pesos de abate sobre o comprimento das carcaças, perímetro de braço e espessura de coxão que aumentaram 5,9; 2,3 e 3,12 cm, respectivamente, quando elevou-se o peso de abate de <340 à >400 kg. Animais abatidos com peso superior à 400 kg apresentaram maior compacidade das carcaças em relação aos demais tratamentos (1,65 cm de comprimento/kg de carcaça fria). Os pesos absolutos dos cortes primários da carcaça aumentaram conforme elevou-se o peso de abate, entretanto ao ajustar os pesos do dianteiro e do traseiro em relação à 100 kg de carcaça fria, esta diferença deixou de existir, apresentando valores de 36,59 e 51,99%, respectivamente. A cor e textura da carne não foram influenciadas pelos pesos de abate apresentando valores médios de 3,28 e 3,19 pontos, respectivamente. O marmoreio da carne, foi menor no grupo de animais abatidos com peso inferior à 340 kg em comparação ás demais classes de peso que não diferiram entre si. Concluiu-se que apesar de não influenciar as principais características da carcaça, a casca de soja não é eficiente para substituir o milho moído em dietas de alta inclusão de concentrado para novilhas confinadas, pois tem efeito depressivo sobre as principais variáveis de desempenho produtivo, notadamente o ganho em peso e a conversão alimentar. Novilhas de descarte da raça Nelore terminadas em confinamento não devem ser abatidas com peso inferior à 340 kg pois apresentam menor peso de carcaça e menor grau de marmoreio da carne.