Currently, feed enzyme supplementation into commercial broiler diets is a routine practice due to hydrolysis of antinutrients, such as non-starch polysaccharides (NSP) and phytate (IP6); ultimately leading to optimized broiler production. As a result, the market has grown rapidly, and a multitude of feed enzymesare commercially available. Complete removal of antinutrients has not been achieved and research has primarily focused on the use of singular enzyme inclusion. Due to biochemical differences among enzyme characteristics, there may be potential for synergistic action to remove antinutrients and further maximize broiler performance. Therefore, the overall objective of this dissertation was to investigate enzyme strategies to determine optimal inclusion for broilers. Chapter 2 investigated the interactive effects of phytase dose (PD; 250 to 1500 FTU/kg) and carbohydrase enzyme (CE) of xylanase (XAN), β-mannanase (MAN), or their combination (XM). These data demonstrated an interaction between CE and PD for d 0-14 FCR, but this significance was lost during the remainder of the study. Overall benefits for performance and processing were demonstrated with feeding a PD of 1500 FTU/kg and XAN. Chapter 3 took a preliminary approach (0-14 d) to investigate the potential synergy among 3 phytase enzymes of varying biochemical properties when fed alone or in combination with low PD (120 or 240 FTU/kg). These data demonstrated potential synergy with the supplementation of 2 phytases combined at a higher PD (240 FTU/kg), as identified from ileal IP (inositol phosphate) lower ester concentration and tibia ash. Chapter 4 built upon the previous chapter, choosing 2 phytases (A or B) and addressing previous limitations by including a broader/more practical range of phytase activity (250 or 1500 FTU/kg); providing 3 diets varying in calcium (Ca) and non-phytate phosphorus (nPP); and using an entire grow-out. Feeding diets lowest in Ca and nPP along with 1500 FTU/kg of A, B, or A+B resulted in improved broiler performance. Additionally, the use of A+B at 250 FTU/kg within diets of medium Ca and nPP levels demonstrated synergism through improved broiler performance and tibia ash. Overall, data suggest that the strategic utilization of enzyme combinations may provide additional benefits towards broiler production.

Distillers dried grains with solubles (DDGS) is a byproduct of distillation. Its increased availability has led to research into overcoming the nutritional limitations of its high non-starch polysaccharide (NSP) content for use in monogastric animal feed. The purpose of this study was to examine the effects of two factors (the inclusion of DDGS and/or inclusion of a carbohydrase mixture) on the richness and abundance of swine gastrointestinal bacteria. The carbohydrase mixture was expected to aid digestion, leading to increased nutritional availability for the host while simultaneously shifting dominant communities within the gut microbiome. Ileal cannulated pigs (n = 8, BW = 64.3 +/-0.5 kg) were allotted to 4 dietary treatments in a replicated 4 x 4 Latin square design. Treatments resulted in changes to bacterial richness, and diets containing DDGS increased the 16S rDNA abundance of members of Bacteroides (P < 0.0001), Ruminococcus (P < 0.0001), the Clostridium coccoides group (P <0.0001), and the Clostridium leptum subgroup (P = 0.005). Significant interactions between diet and carbohydrases were determined for total bacteria in the ileal digesta (P = 0.01) and feces (P = 0.02), Bacteroides (P = 0.003), and the Clostrdium leptum subgroup (P = 0.03). The DDGS diet with the inclusion of the carbohydrases was able to maintain, or increase the abundance of fiber degrading bacteria while theoretically increasing nutrition for the host. / Master of Science in Life Sciences

The nutritional value of an amino acid (AA) is determined by its bioavailability, however concept of digestibility is mostly used in practical situations. Four studies were conducted to test 2 exogenous factors that were hypothesized to affect the AA digestibility in non-ruminant animals. In study 1, broiler chicks were randomly allotted to 4 dietary treatments of control and distillers dried grains with solubles (DDGS, 20%) diets supplemented or not with a novel mixture of carbohydrases. Results indicated the ability of carbohydrase mixture to increase energy utilization of the DDGS diet, with significant improvements in AA digestibility, consequently improving growth performance of broilers. Study 2 examined effect of the carbohydrase mixture in pigs fed a high DDGS diet. Ileal cannulated growing pigs (n = 8, 64.3 ± 0.5 kg) were allotted to 4 dietary treatments in a replicated 4 Ã 4 Latin Square design. Control and DDGS (40%) diets were supplemented or not with a mixture of carbohydrases. Numeric increases for AA digestibility, along with a decreased tendency of urinary energy output suggested a possibility for improved nutrient utilization in pigs when carbohydrases were supplemented to 40% corn DDGS diet. Collectively, carbohydrase seems less effective for swine applications due to greater water content and consequently a lower viscosity in pig digesta. Next, study 3 showed changes in AA digestibility and endogenous AA losses (EAAL) when pigs were challenged orally with Salmonella enterica serovar Typhimurium. Nursery pigs (n = 48, 17.9 ± 0.5 kg) were randomly assigned to a 2 Ã 2 factorial arrangement consisting of two diets (control or N-free) and inoculation (sterile broth or 9.8 Ã 10^9 CFU of Salmonella). Measurements at 24 and 72 h post-inoculation indicated that AA digestibility of pigs is impaired through the initial phase of Salmonella infection and gradually restored, but not fully by 72 h. Finally, study 4 determined the dynamic fluctuations of EAAL and subsequent AA digestibility in response to Salmonella Typhimurium measured at multiple time points. Ileal cannulated pigs (n = 8, 76.0 ± 1.4 kg) were randomly assigned to either a control or a N-free diet and challenged orally with 1.3 Ã 10^10 CFU of Salmonella. Inflammatory diarrhea was associated with reduced AA digestibility and increased EAAL showing respective peak values at 8-16 h post-inoculation. Alterations in AA digestibility and EAAL were gradually recovered to near pre-inoculation values by 56-64 h post-inoculation, but showed impaired digestibility at 72-80 h post-inoculation. / Ph. D.

Parmi les bactéries pathogènes, les entérobactéries occupent une place particulière du fait de leur facilité d’étude génétique et de leur grande diversité d’hôtes. Dickeya dadantii est une bactérie pathogène des plantes, responsable de pourriture sur de nombreux végétaux en culture ou lors de leur stockage. Sa virulence est principalement due à la sécrétion d’enzymes dégradant la paroi végétale. Ce travail de thèse a porté sur la caractérisation génétique et biochimique de glycosidases de D. dadantii afin de comprendre leur importance dans la dégradation des tissus végétaux. Dans ce travail, nous avons montré que D. dadantii est capable d'utiliser le saccharose, le raffinose, ou le mélibiose comme seule source de carbone pour sa croissance grâce aux deux clusters de gènes scrKYABR et rafRBA, incluant les glycosidases RafA (α-galactosidase, famille GH36) et ScrB (sucrose hydrolase, famille GH32). Le cluster raf permet le catabolisme du mélibiose. Le catabolisme du raffinose nécessite deux étapes supplémentaires fournies par les gènes scrY et scrB. En outre, nous avons caractérisé et analysé deux autres gènes. D’une part, le gène bgxA code une β-D-glucosidase/β-xylosidase (famille GH3). Ce gène est induit en présence de sucres et acides phénoliques. D’autre part, le gène xydA code une enzyme à activité α-L-arabinopyranosidase (famille GH43). Ce gène est induit en présence de xylose. Les résultats obtenus suggèrent que BgxA et XydA sont impliquées dans la dégradation de composés végétaux. La mise en évidence de nouvelles enzymes impliqués dans la pathogénie des bactéries envers leurs hôtes ouvrirait la voie à la recherche de stratégies de lutte contre les phytopathogènes. / Enterobacteriaceae are of particular interest among pathogenic bacteria, because of their suitability for genetic studies and their wide range of hosts. Dickeya dadantii is a plant pathogenic bacterium , causing soft rot diseases in a wide range of plant species in culture or during storage. Its virulence is mainly due to the secretion of plant cell wall degrading enzymes. This thesis has focused on genetic and biochemical characterization of D. dadantii glycosidases to understand their importance in the degradation of plant tissues. In this work, we showed that D. dadantii is able to utilize sucrose, raffinose, or melibiose as sole carbon sources for growth. This ability is due of the presence of two gene clusters, scrKYABR and rafRBA, including the glycosidases RafA (α-galactosidase, GH36) and ScrB (sucrose hydrolase, family GH32). The cluster raf allows catabolism of melibiose. Raffinose catabolism requires two additional steps provided by the genes scrY and scrB. In addition, two other genes were analyzed and characterized. On one hand, bgxA encodes a β-D glucosidase/β-xylosidase of the family GH3. This gene is induced in the presence of phenolic sugars and acids On the other hand, XydA encodes an α-L-arabinopyranosidase of the family GH43. This gene is induced in the presence of xylose. The results suggest that BgxA and XydA are involved in the degradation of plant compounds. Identification of new enzymes involved in the pathogenesis of bacteria towards their hosts could open the way for research strategies to fight plant pathogens.

Esse trabalho investigou as principais carboidrases já descritas em Lepidoptera e principalmente as enzimas relacionadas com hidrólise de sacarose presentes na hemolinfa e no intestino do sexto instar larval de Lonomia obliqua. Avaliou também o efeito das diferentes dietas Eriobotrya japonica, Psidium guajava, Mangifera indica e Alchornea ssp sobre as atividades das carboidrases presentes no sistema circulatório e no sistema digestório dessa lagarta. As pectinases e celulases foram identificadas somente no intestino, porém a amilase, a &#945;-glucosidase, a &#946;-glucosidase, a &#945;-fucosidase e a &#946;-fructosidase foram detectadas também na hemolinfa dessa lagarta. Os géis nativos e os pHs ótimos indicam que há distintas carboidrases na hemolinfa e no intestino de Lonomia obliqua. Alterações nas dietas afetam somente as carboidrases intestinais. A sacarose das folhas foi hidrolisada pela ação conjunta da &#945;-glucosidase e da &#946;-frucosidase. A investigação das carboidrases de Lonomia obliqua contribuirão para o desenvolvimento de medidas de controle desse inseto. / This work investigated the main carbohydrases already described in Lepidoptera and especially the enzymes present in the hemolymph and intestine of the 6th instar of Lonomia obliqua related to the hydrolysis of sucrose. It has also evaluated the effect of different diets Alchornea ssp, Eriobotrya japonica, Mangifera indica and Psidium guajava, on the activities of the carbohydrases present in the circulatory and digestive system of this caterpillar. Pectinases and cellulases were identified in the midgut only, but amylase, &#945;-glucosidase, &#946;-glucosidase, &#945;-fucosidase and &#946;-fructosidase were detected in both hemolymph and midgut of this caterpillar. Native gels and effect of pH indicated that there are distinct carboidrases in the hemolymph and the midgut of Lonomia obliqua. Diet change have affected the digestive carbohydrases only. The sucrose in the leaves was hydrolyzed by the combined action of &#945;-glucosidase and &#946;-frucosidase. The investigation of the carboidrases of Lonomia obliqua can contribute to the development of control strategies to this insect.

Objetivou-se avaliar o efeito da suplementação de um complexo enzimático, composto principalmente por endo 1,4 xilanase e endo 1,3(4) β-glucanases (CE), sobre o desempenho produtivo, a digestibilidade de aminoácidos (AA) e a utilização da energia em frangos de corte. Foram alojados 2.016 frangos de corte machos Cobb x Cobb 500 de um dia de idade em 72 boxes experimentais. As aves foram distribuídas em delineamento inteiramente casualizado com 9 tratamentos, 8 repetições e 28 aves por unidade experimental. Os tratamentos consistiram de uma dieta controle, formulada com níveis usuais de energia metabolizável aparente (EMA) e aminoácidos digestíveis (AA dig.) sem a inclusão do CE; e 8 dietas com reduções de EMA (-80 e -120 kcal/kg) e de AA dig. (-3% e 6%), suplementadas ou não com 50 mg/kg do CE. Foi utilizado um programa alimentar de 3 fases: inicial (1 a 21 d), crescimento (22 a 35 d) e final (36 a 42 d). Todas as dietas foram formuladas a base de milho e farelo de soja e com 1% de Celite, utilizado como indicador indigestível. Ganho de peso, consumo de ração e conversão alimentar corrigida para mortalidade (CA) foram avaliados aos 21, 35 e 42 d. Nos dias 21 e 42, 4 aves por unidade experimental foram sacrificadas para coleta de conteúdo ileal e posterior determinação da energia digestivel ileal (EDI) e da digestibilidade de AA. Os dados foram submetidos à análise de variância e, quando significativas, as médias foram comparadas pelo teste de Student-Newman-Keuls a 5% de significância. Contrastes ortogonais foram realizados entre os tratamentos com reduções nutricionais com e sem adição do CE. Frangos alimentados com dietas com reduções de energia e de AA dig. sem a adição do CE apresentaram maior CA e menor EDI quando comparados aos frangos que receberam a suplementação do CE. A suplementação do CE nas dietas aumentou a digestibilidade total de AA aos 21 d, porém não houve efeito aos 42 dias. A maior liberação de energia proporcionada pelo CE foi observada aos 21 d em frangos de corte alimentados com dietas com -120 kcal/kg AME e -6% AA dig., sendo 5,8% maior quando comparados aos alimentados com a dieta análoga sem enzima. Conclui-se que a adição do CE melhorou o desempenho produtivo e resultou em aumento da digestibilidade de AA e do aproveitamento da energia em frangos de corte aos 21 e aos 42 d. / The objective of this study was to evaluate the effect of supplementation of an enzyme complex, composed of endo 1,4 xylanase and endo 1,3 (4) β-glucanases (EC), on the productive performance, amino acid digestibility (AA) and the use of energy in broilers. A total of 2,016 one-day-old Cobb x Cobb 500 male broilers were allocated in 72 floor pens. Chicks were distributed into 9 treatments with 8 replicates of 28 birds each in a completely randomized design. Treatments consisted of a control diet formulated with usual apparent metabolizable energy (AME) and nutrient levels without enzyme supplementation as well as 8 diets having reductions in formulated AME (-80 and -120 kcal/kg) and digestible amino acids (dig. AA; -3 and -6%) supplemented or not with 50 mg/kg of the supplemental enzyme complex. A 3 phases feeding program was used: Starter (1 to 21 d), Grower (22 to 35 d) and Finisher (36 to 42 d). All diets were corn-soybean meal based with 1% of Celite, used as marker. Body weight gain, feed intake and feed conversion corrected for the weight of dead birds (FCR) were evaluated at 21, 35 and 42 d. On days 21 and 42, four birds per experimental unit were sacrificed for ileal content collection and subsequent determination of ileal digestible energy (IDE) and AA digestibility. Data were submitted to analysis of variance and, when significant, the means were compared by the Student-Newman-Keuls test at 5% significance. Orthogonal contrasts were performed between treatments with nutritional reductions with and without EC addition. Diets with AME and dig. AA reductions without enzyme had higher FCR and lower IDE (P < 0.05). The supplemental enzyme increased total AA digestibility at 21 d; however, no effects were observed at 42 d. The highest energy improvement provided by the supplemental enzyme was observed at 21 d on broilers fed diets with -120 kcal/kg AME and -6% dig. AA, being 5.8% higher when compared to those fed the analogous diet without enzyme. Summarizing, the addition of EC led to improvements on growth performance, digestibility of AA and energy utilization on broilers at 21 and 42 d.

As enzimas exógenas são mecanismos de redução de custos e otimização da eficiência do uso de ingredientes aumentando a digestão e reduzindo a excreção de nutrientes ao ambiente. Desta forma, foram realizados dois experimentos para avaliar o efeito da adição de enzima exógena sobre o desempenho e qualidade dos ovos de poedeiras comerciais. O primeiro estudo teve como intuito avaliar os efeitos da dieta com nutrientes reduzidos e suplementados com fitase para poedeiras comerciais de 70 a 86 semanas de idade sobre as características de desempenho, qualidade do ovo e parâmetros econômicos. As poedeiras comerciais Novogen White ® (n = 256) foram distribuídas de acordo com um delineamento inteiramente casualizado em quatro tratamentos, com oito repetições de oito galinhas cada: controle positivo (CP): dieta convencional, não suplementada com fitase; dieta com níveis reduzidos de P (-0.12%), Ca (-0.10%) e ME (-14 kcal / kg) e suplementados com 300 FTU fitase / kg (CN300FTU); dieta com níveis reduzidos de P (-0,16%), Ca (-0,13%), ME (-18 kcal / kg), CP (-18%), aminoácidos sintéticos (-0,01%) e suplementados com 600 FTU fitase / kg (RN600FTU); e dieta com níveis reduzidos de P (-0.18% P), Ca (-0.15%), ME (-20 kcal / kg), CP (-20%), aminoácidos sintéticos (-0,01%) e suplementados com 900 FTU fitase / kg (CN900FTU). Durante o experimento foi coletado os dados desempenho, a qualidade dos ovos e os dados de análise econômica. As poedeiras alimentadas com a dieta CN300FTU apresentaram uma produção de ovos 2,68% maior que as alimentadas com a dieta CP. As poedeiras alimentadas com CP tiveram os ovos mais pesados (66,80 g). A massa de ovos produzida por poedeiras alimentadas com CP e CN300FTU foi estatisticamente similar. As características de qualidade dos ovos não foram influenciadas pelos tratamentos dietéticos, com exceção da espessura da casca do ovo, cujo maior valor foi obtido nas poedeiras alimentadas por CP. O custo da ração da dieta CN900FTU foi aproximadamente 9% menor do que o da dieta CP. Este estudo mostrou que as poedeiras alimentadas com uma dieta de nutrientes reduzidos e suplementados com fitase de 300FTU produziram o melhor desempenho e resultados econômicos. No segundo experimento, foi avaliado os efeitos dos níveis de energia metabolizável e suplementadas com complexo enzimático para poedeiras comerciais, de segundo ciclo, de 84 a 100 semanas de idade em seu desempenho, qualidade do ovo e parâmetros econômicos. As poedeiras comerciais Hy-line White ® (n = 224) foram distribuídas de acordo com um delineamento inteiramente casualizado em esquema fatorial 2 X 2, dois níveis de energia metabolizável (2.626, 2.776 Kcal de energia metabolizável) e com e sem suplementação de carboidrase (5g/t), totalizando quatro tratamentos com sete repetições. Houve interação entre o nível de energia e o complexo enzimático para produção e massa de ovo. Sendo, maior produtividade e massa de ovos foi para as poedeiras alimentadas com maior nível de energia e a suplementada com o complexo enzimático. Conclui-se que a suplementação de enzimas exógenas (fitase e carboidrase) para poedeiras comerciais nos dois experimentos apresentou efeitos satisfatórios para as características zootécnicas e econômicas. / The exogenous enzymes are mechanisms for cost reduction and optimization of the efficiency of the use of ingredients enhancing digestion and reducing the excretion of nutrients. In this way, two independent experiments were performed to evaluate the effect the addition of exogenous enzyme on egg production and quality characteristics of the egg of laying hens. The firty study, the objective of this study was to evaluate the effects of feeding reduced-nutrient diets supplemented with phytase to commercial laying hens from 70 to 86 weeks of age on their performance, egg quality, and economic parameters. Novogen White ® commercial laying hens (n=256) were distributed according to a completely randomized design into four treatments, with eight replicates of eight hens each: Positive control: conventional diet, not supplemented with phytase; diet with reduced levels of P (-0.12%), Ca (-0.10%), and ME (-14 kcal/kg), and supplemented with 300 FTU phytase/kg (RN300FTU); diet with reduced levels of P (-0.16%), Ca (-0.13%), ME (-18 kcal/kg), CP (-18%), synthetic amino acids (-0,01%), and supplemented with 600 FTU phytase/kg (RN600FTU); and diet with reduced levels of P (-0.18% P), Ca (-0.15%), ME (-20 kcal/kg), CP (-20%), synthetic amino acids (-0,01%), and supplemented with 900 FTU phytase/kg (RN900FTU). Performance, egg quality, and economic parameters data were collected during the experiment. The layers fed the RN300FTU diet presented 2.68% higher egg production than those fed the PC diet. PC-fed hens laid the heaviest eggs (66.80g). Egg mass produced by PC- and RN300FTU-fed hens were statistically similar. Egg quality traits were not influenced by the dietary treatments, except for eggshell thickness, which highest value was obtained in the PC-fed hens. The feeding cost of the RN900FTU diet was approximately 9% lower compared with that of the PC diet. This study showed that feeding layers with a reduced-nutrient diet supplemented with 300FTU phytase yielded the best performance and economic results. In the second experiment, study was to evaluate the effects of feeding levels of metabolizable energy diets supplemented with enzymatic complex to commercial laying hens, second cycle, from 84 to 100 weeks of age on their performance, egg quality, and economic parameters. Novogen White ® commercial laying hens (n=256) were distributed according to a completely randomized design into four treatments, with eight replicates of eight hens each: Positive control: conventional diet, not supplemented with phytase. Hy-line White ® commercial laying hens (n= 224) were distributed according to a completely randomized design into factorial arrangement 2 X 2, two levels of metabolizable energy (2,626, 2,776 Kcal of metabolizable energy) and with and without supplementation carbohydrase (0, 5 / t), totaling four treatments with seven repetitions. There was interaction between the energy level and the enzymatic complex for production and egg mass. Being, greater productivity and egg mass was for layers that had the highest energy level and the inclusion of the enzyme complex. It was concluded that the supplementation of exogenous enzymes (phytase and carbohydrase) for commercial laying hens in both experiments presented satisfactory effects for the zootechnical and economic characteristics.

Objetivou-se avaliar o efeito da suplementação de um complexo enzimático, composto principalmente por endo 1,4 xilanase e endo 1,3(4) β-glucanases (CE), sobre o desempenho produtivo, a digestibilidade de aminoácidos (AA) e a utilização da energia em frangos de corte. Foram alojados 2.016 frangos de corte machos Cobb x Cobb 500 de um dia de idade em 72 boxes experimentais. As aves foram distribuídas em delineamento inteiramente casualizado com 9 tratamentos, 8 repetições e 28 aves por unidade experimental. Os tratamentos consistiram de uma dieta controle, formulada com níveis usuais de energia metabolizável aparente (EMA) e aminoácidos digestíveis (AA dig.) sem a inclusão do CE; e 8 dietas com reduções de EMA (-80 e -120 kcal/kg) e de AA dig. (-3% e 6%), suplementadas ou não com 50 mg/kg do CE. Foi utilizado um programa alimentar de 3 fases: inicial (1 a 21 d), crescimento (22 a 35 d) e final (36 a 42 d). Todas as dietas foram formuladas a base de milho e farelo de soja e com 1% de Celite, utilizado como indicador indigestível. Ganho de peso, consumo de ração e conversão alimentar corrigida para mortalidade (CA) foram avaliados aos 21, 35 e 42 d. Nos dias 21 e 42, 4 aves por unidade experimental foram sacrificadas para coleta de conteúdo ileal e posterior determinação da energia digestivel ileal (EDI) e da digestibilidade de AA. Os dados foram submetidos à análise de variância e, quando significativas, as médias foram comparadas pelo teste de Student-Newman-Keuls a 5% de significância. Contrastes ortogonais foram realizados entre os tratamentos com reduções nutricionais com e sem adição do CE. Frangos alimentados com dietas com reduções de energia e de AA dig. sem a adição do CE apresentaram maior CA e menor EDI quando comparados aos frangos que receberam a suplementação do CE. A suplementação do CE nas dietas aumentou a digestibilidade total de AA aos 21 d, porém não houve efeito aos 42 dias. A maior liberação de energia proporcionada pelo CE foi observada aos 21 d em frangos de corte alimentados com dietas com -120 kcal/kg AME e -6% AA dig., sendo 5,8% maior quando comparados aos alimentados com a dieta análoga sem enzima. Conclui-se que a adição do CE melhorou o desempenho produtivo e resultou em aumento da digestibilidade de AA e do aproveitamento da energia em frangos de corte aos 21 e aos 42 d. / The objective of this study was to evaluate the effect of supplementation of an enzyme complex, composed of endo 1,4 xylanase and endo 1,3 (4) β-glucanases (EC), on the productive performance, amino acid digestibility (AA) and the use of energy in broilers. A total of 2,016 one-day-old Cobb x Cobb 500 male broilers were allocated in 72 floor pens. Chicks were distributed into 9 treatments with 8 replicates of 28 birds each in a completely randomized design. Treatments consisted of a control diet formulated with usual apparent metabolizable energy (AME) and nutrient levels without enzyme supplementation as well as 8 diets having reductions in formulated AME (-80 and -120 kcal/kg) and digestible amino acids (dig. AA; -3 and -6%) supplemented or not with 50 mg/kg of the supplemental enzyme complex. A 3 phases feeding program was used: Starter (1 to 21 d), Grower (22 to 35 d) and Finisher (36 to 42 d). All diets were corn-soybean meal based with 1% of Celite, used as marker. Body weight gain, feed intake and feed conversion corrected for the weight of dead birds (FCR) were evaluated at 21, 35 and 42 d. On days 21 and 42, four birds per experimental unit were sacrificed for ileal content collection and subsequent determination of ileal digestible energy (IDE) and AA digestibility. Data were submitted to analysis of variance and, when significant, the means were compared by the Student-Newman-Keuls test at 5% significance. Orthogonal contrasts were performed between treatments with nutritional reductions with and without EC addition. Diets with AME and dig. AA reductions without enzyme had higher FCR and lower IDE (P < 0.05). The supplemental enzyme increased total AA digestibility at 21 d; however, no effects were observed at 42 d. The highest energy improvement provided by the supplemental enzyme was observed at 21 d on broilers fed diets with -120 kcal/kg AME and -6% dig. AA, being 5.8% higher when compared to those fed the analogous diet without enzyme. Summarizing, the addition of EC led to improvements on growth performance, digestibility of AA and energy utilization on broilers at 21 and 42 d.

Objetivou-se avaliar o efeito da suplementação de um complexo enzimático, composto principalmente por endo 1,4 xilanase e endo 1,3(4) β-glucanases (CE), sobre o desempenho produtivo, a digestibilidade de aminoácidos (AA) e a utilização da energia em frangos de corte. Foram alojados 2.016 frangos de corte machos Cobb x Cobb 500 de um dia de idade em 72 boxes experimentais. As aves foram distribuídas em delineamento inteiramente casualizado com 9 tratamentos, 8 repetições e 28 aves por unidade experimental. Os tratamentos consistiram de uma dieta controle, formulada com níveis usuais de energia metabolizável aparente (EMA) e aminoácidos digestíveis (AA dig.) sem a inclusão do CE; e 8 dietas com reduções de EMA (-80 e -120 kcal/kg) e de AA dig. (-3% e 6%), suplementadas ou não com 50 mg/kg do CE. Foi utilizado um programa alimentar de 3 fases: inicial (1 a 21 d), crescimento (22 a 35 d) e final (36 a 42 d). Todas as dietas foram formuladas a base de milho e farelo de soja e com 1% de Celite, utilizado como indicador indigestível. Ganho de peso, consumo de ração e conversão alimentar corrigida para mortalidade (CA) foram avaliados aos 21, 35 e 42 d. Nos dias 21 e 42, 4 aves por unidade experimental foram sacrificadas para coleta de conteúdo ileal e posterior determinação da energia digestivel ileal (EDI) e da digestibilidade de AA. Os dados foram submetidos à análise de variância e, quando significativas, as médias foram comparadas pelo teste de Student-Newman-Keuls a 5% de significância. Contrastes ortogonais foram realizados entre os tratamentos com reduções nutricionais com e sem adição do CE. Frangos alimentados com dietas com reduções de energia e de AA dig. sem a adição do CE apresentaram maior CA e menor EDI quando comparados aos frangos que receberam a suplementação do CE. A suplementação do CE nas dietas aumentou a digestibilidade total de AA aos 21 d, porém não houve efeito aos 42 dias. A maior liberação de energia proporcionada pelo CE foi observada aos 21 d em frangos de corte alimentados com dietas com -120 kcal/kg AME e -6% AA dig., sendo 5,8% maior quando comparados aos alimentados com a dieta análoga sem enzima. Conclui-se que a adição do CE melhorou o desempenho produtivo e resultou em aumento da digestibilidade de AA e do aproveitamento da energia em frangos de corte aos 21 e aos 42 d. / The objective of this study was to evaluate the effect of supplementation of an enzyme complex, composed of endo 1,4 xylanase and endo 1,3 (4) β-glucanases (EC), on the productive performance, amino acid digestibility (AA) and the use of energy in broilers. A total of 2,016 one-day-old Cobb x Cobb 500 male broilers were allocated in 72 floor pens. Chicks were distributed into 9 treatments with 8 replicates of 28 birds each in a completely randomized design. Treatments consisted of a control diet formulated with usual apparent metabolizable energy (AME) and nutrient levels without enzyme supplementation as well as 8 diets having reductions in formulated AME (-80 and -120 kcal/kg) and digestible amino acids (dig. AA; -3 and -6%) supplemented or not with 50 mg/kg of the supplemental enzyme complex. A 3 phases feeding program was used: Starter (1 to 21 d), Grower (22 to 35 d) and Finisher (36 to 42 d). All diets were corn-soybean meal based with 1% of Celite, used as marker. Body weight gain, feed intake and feed conversion corrected for the weight of dead birds (FCR) were evaluated at 21, 35 and 42 d. On days 21 and 42, four birds per experimental unit were sacrificed for ileal content collection and subsequent determination of ileal digestible energy (IDE) and AA digestibility. Data were submitted to analysis of variance and, when significant, the means were compared by the Student-Newman-Keuls test at 5% significance. Orthogonal contrasts were performed between treatments with nutritional reductions with and without EC addition. Diets with AME and dig. AA reductions without enzyme had higher FCR and lower IDE (P < 0.05). The supplemental enzyme increased total AA digestibility at 21 d; however, no effects were observed at 42 d. The highest energy improvement provided by the supplemental enzyme was observed at 21 d on broilers fed diets with -120 kcal/kg AME and -6% dig. AA, being 5.8% higher when compared to those fed the analogous diet without enzyme. Summarizing, the addition of EC led to improvements on growth performance, digestibility of AA and energy utilization on broilers at 21 and 42 d.

As enzimas exógenas são mecanismos de redução de custos e otimização da eficiência do uso de ingredientes aumentando a digestão e reduzindo a excreção de nutrientes ao ambiente. Desta forma, foram realizados dois experimentos para avaliar o efeito da adição de enzima exógena sobre o desempenho e qualidade dos ovos de poedeiras comerciais. O primeiro estudo teve como intuito avaliar os efeitos da dieta com nutrientes reduzidos e suplementados com fitase para poedeiras comerciais de 70 a 86 semanas de idade sobre as características de desempenho, qualidade do ovo e parâmetros econômicos. As poedeiras comerciais Novogen White ® (n = 256) foram distribuídas de acordo com um delineamento inteiramente casualizado em quatro tratamentos, com oito repetições de oito galinhas cada: controle positivo (CP): dieta convencional, não suplementada com fitase; dieta com níveis reduzidos de P (-0.12%), Ca (-0.10%) e ME (-14 kcal / kg) e suplementados com 300 FTU fitase / kg (CN300FTU); dieta com níveis reduzidos de P (-0,16%), Ca (-0,13%), ME (-18 kcal / kg), CP (-18%), aminoácidos sintéticos (-0,01%) e suplementados com 600 FTU fitase / kg (RN600FTU); e dieta com níveis reduzidos de P (-0.18% P), Ca (-0.15%), ME (-20 kcal / kg), CP (-20%), aminoácidos sintéticos (-0,01%) e suplementados com 900 FTU fitase / kg (CN900FTU). Durante o experimento foi coletado os dados desempenho, a qualidade dos ovos e os dados de análise econômica. As poedeiras alimentadas com a dieta CN300FTU apresentaram uma produção de ovos 2,68% maior que as alimentadas com a dieta CP. As poedeiras alimentadas com CP tiveram os ovos mais pesados (66,80 g). A massa de ovos produzida por poedeiras alimentadas com CP e CN300FTU foi estatisticamente similar. As características de qualidade dos ovos não foram influenciadas pelos tratamentos dietéticos, com exceção da espessura da casca do ovo, cujo maior valor foi obtido nas poedeiras alimentadas por CP. O custo da ração da dieta CN900FTU foi aproximadamente 9% menor do que o da dieta CP. Este estudo mostrou que as poedeiras alimentadas com uma dieta de nutrientes reduzidos e suplementados com fitase de 300FTU produziram o melhor desempenho e resultados econômicos. No segundo experimento, foi avaliado os efeitos dos níveis de energia metabolizável e suplementadas com complexo enzimático para poedeiras comerciais, de segundo ciclo, de 84 a 100 semanas de idade em seu desempenho, qualidade do ovo e parâmetros econômicos. As poedeiras comerciais Hy-line White ® (n = 224) foram distribuídas de acordo com um delineamento inteiramente casualizado em esquema fatorial 2 X 2, dois níveis de energia metabolizável (2.626, 2.776 Kcal de energia metabolizável) e com e sem suplementação de carboidrase (5g/t), totalizando quatro tratamentos com sete repetições. Houve interação entre o nível de energia e o complexo enzimático para produção e massa de ovo. Sendo, maior produtividade e massa de ovos foi para as poedeiras alimentadas com maior nível de energia e a suplementada com o complexo enzimático. Conclui-se que a suplementação de enzimas exógenas (fitase e carboidrase) para poedeiras comerciais nos dois experimentos apresentou efeitos satisfatórios para as características zootécnicas e econômicas. / The exogenous enzymes are mechanisms for cost reduction and optimization of the efficiency of the use of ingredients enhancing digestion and reducing the excretion of nutrients. In this way, two independent experiments were performed to evaluate the effect the addition of exogenous enzyme on egg production and quality characteristics of the egg of laying hens. The firty study, the objective of this study was to evaluate the effects of feeding reduced-nutrient diets supplemented with phytase to commercial laying hens from 70 to 86 weeks of age on their performance, egg quality, and economic parameters. Novogen White ® commercial laying hens (n=256) were distributed according to a completely randomized design into four treatments, with eight replicates of eight hens each: Positive control: conventional diet, not supplemented with phytase; diet with reduced levels of P (-0.12%), Ca (-0.10%), and ME (-14 kcal/kg), and supplemented with 300 FTU phytase/kg (RN300FTU); diet with reduced levels of P (-0.16%), Ca (-0.13%), ME (-18 kcal/kg), CP (-18%), synthetic amino acids (-0,01%), and supplemented with 600 FTU phytase/kg (RN600FTU); and diet with reduced levels of P (-0.18% P), Ca (-0.15%), ME (-20 kcal/kg), CP (-20%), synthetic amino acids (-0,01%), and supplemented with 900 FTU phytase/kg (RN900FTU). Performance, egg quality, and economic parameters data were collected during the experiment. The layers fed the RN300FTU diet presented 2.68% higher egg production than those fed the PC diet. PC-fed hens laid the heaviest eggs (66.80g). Egg mass produced by PC- and RN300FTU-fed hens were statistically similar. Egg quality traits were not influenced by the dietary treatments, except for eggshell thickness, which highest value was obtained in the PC-fed hens. The feeding cost of the RN900FTU diet was approximately 9% lower compared with that of the PC diet. This study showed that feeding layers with a reduced-nutrient diet supplemented with 300FTU phytase yielded the best performance and economic results. In the second experiment, study was to evaluate the effects of feeding levels of metabolizable energy diets supplemented with enzymatic complex to commercial laying hens, second cycle, from 84 to 100 weeks of age on their performance, egg quality, and economic parameters. Novogen White ® commercial laying hens (n=256) were distributed according to a completely randomized design into four treatments, with eight replicates of eight hens each: Positive control: conventional diet, not supplemented with phytase. Hy-line White ® commercial laying hens (n= 224) were distributed according to a completely randomized design into factorial arrangement 2 X 2, two levels of metabolizable energy (2,626, 2,776 Kcal of metabolizable energy) and with and without supplementation carbohydrase (0, 5 / t), totaling four treatments with seven repetitions. There was interaction between the energy level and the enzymatic complex for production and egg mass. Being, greater productivity and egg mass was for layers that had the highest energy level and the inclusion of the enzyme complex. It was concluded that the supplementation of exogenous enzymes (phytase and carbohydrase) for commercial laying hens in both experiments presented satisfactory effects for the zootechnical and economic characteristics.