Different sieving methods for determining the physical characteristics in ground corn

We evaluated various sieving methods to estimate particle size (PS) and geometric standard deviation (GSD) of ground corn. The corn had been previously divided in six fractions and each one ground in a hammermill (1-, 2-, 3-, 4-, 5- or 12-mm sieves). The stacked sieving method, with prior drying at 105ºC without agitators was the reference. We evaluated eight sieving methods, distributed in a factorial design (2 x 2 x 2 x 6), consisting of the following treatments: i) with and without agitators (two 25-mm rubber spheres), ii) with and without previous drying, iii) with a nest of test sieves set in a stacked or reverse, and iv) employing six ground corn degrees, totaling 48 treatments (four replicates). There was a linear increase in PS estimation for methods without drying and stacking and quadratic increases for the others. Reverse, drying, and agitator methodologies gave better sieving of corn, and consequently gave the lowest PS and highest GSD. The results were more pronounced for high-intensity grinding (hammermill sieve with small apertures) in which the differences between the reference method with the drying and reverse methods were up to 210 µm. Reverse sieving combined with agitators allowed the greatest passage of corn particles through the test sieves and promoted better characterization of ground corn.(AU)

Different sieving methods for determining the physical characteristics in ground corn

We evaluated various sieving methods to estimate particle size (PS) and geometric standard deviation (GSD) of ground corn. The corn had been previously divided in six fractions and each one ground in a hammermill (1-, 2-, 3-, 4-, 5-or 12-mm sieves). The stacked sieving method, with prior drying at 105ºC without agitators was the reference. We evaluated eight sieving methods, distributed in a factorial design(2 x 2 x 2 x 6), consisting of the following treatments: i) with and without agitators (two 25-mm rubber spheres), ii) with and without previous drying, iii) with a nest of test sieves set in a stacked or reverse, and iv) employing six ground corn degrees, totaling 48 treatments (four replicates). There was a linear increase in PS estimation for methods without drying and stacking and quadratic increases for the others. Reverse, drying, and agitator methodologies gave better sieving of corn, and consequently gave the lowest PS andhighest GSD. The results were more pronounced for high-intensity grinding (hammermill sieve with small apertures) in which the differences between the reference method with the drying and reverse methods were up to 210 &956;m. Reverse sieving combined with agitators allowed the greatest passage of corn particles through the test sieves and promoted better characterization of ground corn.(AU)

Different sieving methods for determining the physical characteristics in ground corn / Different sieving methods for determining the physical characteristics in ground corn

We evaluated various sieving methods to estimate particle size (PS) and geometric standard deviation (GSD) of ground corn. The corn had been previously divided in six fractions and each one ground in a hammermill (1-, 2-, 3-, 4-, 5- or 12-mm sieves). The stacked sieving method, with prior drying at 105ºC without agitators was the reference. We evaluated eight sieving methods, distributed in a factorial design (2 x 2 x 2 x 6), consisting of the following treatments: i) with and without agitators (two 25-mm rubber spheres), ii) with and without previous drying, iii) with a nest of test sieves set in a stacked or reverse, and iv) employing six ground corn degrees, totaling 48 treatments (four replicates). There was a linear increase in PS estimation for methods without drying and stacking and quadratic increases for the others. Reverse, drying, and agitator methodologies gave better sieving of corn, and consequently gave the lowest PS and highest GSD. The results were more pronounced for high-intensity grinding (hammermill sieve with small apertures) in which the differences between the reference method with the drying and reverse methods were up to 210 µm. Reverse sieving combined with agitators allowed the greatest passage of corn particles through the test sieves and promoted better characterization of ground corn.

We evaluated various sieving methods to estimate particle size (PS) and geometric standard deviation (GSD) of ground corn. The corn had been previously divided in six fractions and each one ground in a hammermill (1-, 2-, 3-, 4-, 5- or 12-mm sieves). The stacked sieving method, with prior drying at 105ºC without agitators was the reference. We evaluated eight sieving methods, distributed in a factorial design (2 x 2 x 2 x 6), consisting of the following treatments: i) with and without agitators (two 25-mm rubber spheres), ii) with and without previous drying, iii) with a nest of test sieves set in a stacked or reverse, and iv) employing six ground corn degrees, totaling 48 treatments (four replicates). There was a linear increase in PS estimation for methods without drying and stacking and quadratic increases for the others. Reverse, drying, and agitator methodologies gave better sieving of corn, and consequently gave the lowest PS and highest GSD. The results were more pronounced for high-intensity grinding (hammermill sieve with small apertures) in which the differences between the reference method with the drying and reverse methods were up to 210 µm. Reverse sieving combined with agitators allowed the greatest passage of corn particles through the test sieves and promoted better characterization of ground corn.

Digestibilidade de nutrientes da silagem de grãos úmidos de milho para leitões com e sem inoculação microbiana / Digestibility of nutrients from moist corn grain silage for piglets with and without microbial inoculation

Foram realizados dois experimentos para avaliar o padrão de fermentação e digestibilidade dos nutrientes de silagens de grãos úmidos de milho (SGUM), de milho cv. SCS 154 Fortuna Epagri® e de milho doce Tropical Syngenta®, com ou sem inoculação microbiana, para leitões. Para os experimentos, foi utilizado um delineamento em esquema fatorial 2*2 (duas variedades de milho e com ou sem inoculação). Para o experimento de ensilagem foram fabricados três silos para cada tratamento. A abertura dos silos e as análises (matéria seca - MS, matéria orgânica - MO, proteína bruta – PB e Acidez titulável - AT) foram realizadas aos 45 dias pós-ensilagem. Para o ensaio de digestibilidade, foram utilizados 20 leitões machos castrados (um animal por unidade experimental), com peso inicial médio de 10,9±1,1kg, com quatro repetições por tratamento, sendo adicionalmente elaborado um tratamento referência (dieta sem inclusão de silagens) para permitir, via coeficiente angular, estimar os coeficientes de digestibilidade dos nutrientes das silagens. Houve interação da inoculação com a variedade de milho (p<0,05) para AT e o tratamento sem inoculação apresentou os maiores valores de AT para o milho doce Tropical e para o milho Fortuna maior AT quando inoculado. A SGUM de milho Fortuna apresentou melhores coeficientes de digestibilidade e energia da MS do que as silagens fabricadas com milho doce Tropical. Corrigidos para 88% de MS o milho Fortuna apresentou 3,45 Mcal de EM/kg e o milho doce Tropical 3,41 Mcal de EM/kg. A inoculação bacteriana não influenciou a composição química das silagens e os coeficientes de digestibilidade e metabolização.

Two experiments were carried out to evaluate fermentation and digestibility patterns of nutrients from moist corn grain silages (MCGS), corn cv. SCS 154 Fortuna Epagri® and Tropical Syngenta® sweet corn, with or without microbial inoculation for piglets. For the experiments, a factorial design of 2*2 was used (two types of corn and with or without inoculation). For the silage experiment, three silos were built for each treatment. The opening of silos and analyzes (dry matter - DM, organic matter - OM, crude protein - CP and titratable acidity - TA) were performed 45 days after ensiling. For the digestibility test, 20 castrated male piglets (one pig per experimental unit) with an average initial weight of 10.9±1.1kg, with four replicates per treatment, with an additional reference treatment (diet without silages) permitted by angular coefficient to estimate the nutrients digestibility coefficients of grain silages. There was interaction of inoculation with the corn variety (p<0.05) for TA and the treatment without inoculation showed the highest TA values for Tropical sweet corn and higher TA when inoculated for the Fortuna. Fortuna MCGS showed better DM and energy digestibility coefficients than silages made with Tropical sweet corn. Corrected for 88% of DM, Fortuna corn presented 3.45 Mcal of ME/kg, and Tropical sweet corn 3.41 Mcal of ME/kg. Bacterial inoculation did not influence the chemical composition of the silages, digestibility or metabolization coefficients.

Digestibilidade de nutrientes da silagem de grãos úmidos de milho para leitões com e sem inoculação microbiana / Digestibility of nutrients from moist corn grain silage for piglets with and without microbial inoculation

Foram realizados dois experimentos para avaliar o padrão de fermentação e digestibilidade dos nutrientes de silagens de grãos úmidos de milho (SGUM), de milho cv. SCS 154 Fortuna Epagri® e de milho doce Tropical Syngenta®, com ou sem inoculação microbiana, para leitões. Para os experimentos, foi utilizado um delineamento em esquema fatorial 2*2 (duas variedades de milho e com ou sem inoculação). Para o experimento de ensilagem foram fabricados três silos para cada tratamento. A abertura dos silos e as análises (matéria seca - MS, matéria orgânica - MO, proteína bruta PB e Acidez titulável - AT) foram realizadas aos 45 dias pós-ensilagem. Para o ensaio de digestibilidade, foram utilizados 20 leitões machos castrados (um animal por unidade experimental), com peso inicial médio de 10,9±1,1kg, com quatro repetições por tratamento, sendo adicionalmente elaborado um tratamento referência (dieta sem inclusão de silagens) para permitir, via coeficiente angular, estimar os coeficientes de digestibilidade dos nutrientes das silagens. Houve interação da inoculação com a variedade de milho (p<0,05) para AT e o tratamento sem inoculação apresentou os maiores valores de AT para o milho doce Tropical e para o milho Fortuna maior AT quando inoculado. A SGUM de milho Fortuna apresentou melhores coeficientes de digestibilidade e energia da MS do que as silagens fabricadas com milho doce Tropical. Corrigidos para 88% de MS o milho Fortuna apresentou 3,45 Mcal de EM/kg e o milho doce Tropical 3,41 Mcal de EM/kg. A inoculação bacteriana não influenciou a composição química das silagens e os coeficientes de digestibilidade e metabolização.(AU)

Two experiments were carried out to evaluate fermentation and digestibility patterns of nutrients from moist corn grain silages (MCGS), corn cv. SCS 154 Fortuna Epagri® and Tropical Syngenta® sweet corn, with or without microbial inoculation for piglets. For the experiments, a factorial design of 2*2 was used (two types of corn and with or without inoculation). For the silage experiment, three silos were built for each treatment. The opening of silos and analyzes (dry matter - DM, organic matter - OM, crude protein - CP and titratable acidity - TA) were performed 45 days after ensiling. For the digestibility test, 20 castrated male piglets (one pig per experimental unit) with an average initial weight of 10.9±1.1kg, with four replicates per treatment, with an additional reference treatment (diet without silages) permitted by angular coefficient to estimate the nutrients digestibility coefficients of grain silages. There was interaction of inoculation with the corn variety (p<0.05) for TA and the treatment without inoculation showed the highest TA values for Tropical sweet corn and higher TA when inoculated for the Fortuna. Fortuna MCGS showed better DM and energy digestibility coefficients than silages made with Tropical sweet corn. Corrected for 88% of DM, Fortuna corn presented 3.45 Mcal of ME/kg, and Tropical sweet corn 3.41 Mcal of ME/kg. Bacterial inoculation did not influence the chemical composition of the silages, digestibility or metabolization coefficients.(AU)

Conservation of the rice bran for silage with different levels of hydration and addition of cornmeal / Conservação do farelo de arroz integral por ensilagem com diferentes graus de hidratação e adição de fubá de milho

A study was carried out to evaluate the addition of cornmeal (FMI) at different hydration degrees to rice bran, as a strategy for its conservation by silage (FAR). Five relations of FAR and FMI were used: 10:0; 9:1; 8:2; 7:3 and 6:4, combined with five hydration levels: 10, 20, 30, 40 and 50% over initial weight, performing a 5x5 factorial design with four replications. In parallel, were prepared four similar silos only with FAR, without hydration (control silos). After 120 days of storage, the pH, titratable acidity, acidity index, fungi index, and water activity (Aw) were evaluated. The temperature (regarding to verify the aerobic stability) and the pH were determined at 24, 48 and 120 hour after opening. Interactions were observed for pH at opening time, titratable acidity, acid index and fungi index. No interactions were observed with Aw. The inclusion of 40% of cornmeal and 42.3% water improved the silage pH at opening and 43,6% improve the silage pH at 24 hours after opening. However, after 48 h of opening, all silages were inappropriate for consumption, the addition of cornmeal accelerated the deterioration of silage. Only on the control silos, the peroxidation process was observed. Then, the use of silage method for preserving the quality of rice bran was promising as a tool to reduce peroxidation independent of hydration level.(AU)

Foi conduzido um estudo para avaliar diferentes graus de hidratação e adição de fubá de milho (FMI) para a ensilagem do farelo de arroz integral (FAR) para conservação do produto. Foram utilizadas relações FAR: FMI 10:0; 9:1; 8:2; 7:3 e 6:4 e níveis de hidratação da mistura 10, 20, 30, 40 e 50% do peso inicial, perfazendo um esquema fatorial de 5x5 com quatro repetições. Paralelamente, foram fabricados quatro silos de características semelhantes aos demais com FAR sem a hidratação, denominados silos referência, e avaliada a peroxidação lipídica. Após a abertura (120 dias de ensilagem) foram avaliados o pH, acidez titulável (AT), índice de acidez (IA), índice de fungos (IF) e atividade de água (Aw). A temperatura (análise para verificar a estabilidade aeróbica) e o pH, pós abertura, foram determinados em 24, 48 e 120 horas após a abertura. Houve interações entre as variáveis para: pH na abertura, AT, IA e IF. Para a variável Aw não houve interação. A inclusão de 40% de FMI e 42,3% de água melhorou o pH da silagem na abertura, e a inclusão de 43,6% de água melhorou o pH 24 horas pós abertura. Após 48 horas de abertura as silagens estavam inapropriadas para o consumo, e a inclusão do milho acelerou a deterioração da massa ensilada após este período. Somente nos silos controles foi observado peroxidação lipídica.(AU)

Conservation of the rice bran for silage with different levels of hydration and addition of cornmeal / Conservação do farelo de arroz integral por ensilagem com diferentes graus de hidratação e adição de fubá de milho

A study was carried out to evaluate the addition of cornmeal (FMI) at different hydration degrees to rice bran, as a strategy for its conservation by silage (FAR). Five relations of FAR and FMI were used: 10:0; 9:1; 8:2; 7:3 and 6:4, combined with five hydration levels: 10, 20, 30, 40 and 50% over initial weight, performing a 5x5 factorial design with four replications. In parallel, were prepared four similar silos only with FAR, without hydration (control silos). After 120 days of storage, the pH, titratable acidity, acidity index, fungi index, and water activity (Aw) were evaluated. The temperature (regarding to verify the aerobic stability) and the pH were determined at 24, 48 and 120 hour after opening. Interactions were observed for pH at opening time, titratable acidity, acid index and fungi index. No interactions were observed with Aw. The inclusion of 40% of cornmeal and 42.3% water improved the silage pH at opening and 43,6% improve the silage pH at 24 hours after opening. However, after 48 h of opening, all silages were inappropriate for consumption, the addition of cornmeal accelerated the deterioration of silage. Only on the control silos, the peroxidation process was observed. Then, the use of silage method for preserving the quality of rice bran was promising as a tool to reduce peroxidation independent of hydration level.

Foi conduzido um estudo para avaliar diferentes graus de hidratação e adição de fubá de milho (FMI) para a ensilagem do farelo de arroz integral (FAR) para conservação do produto. Foram utilizadas relações FAR: FMI 10:0; 9:1; 8:2; 7:3 e 6:4 e níveis de hidratação da mistura 10, 20, 30, 40 e 50% do peso inicial, perfazendo um esquema fatorial de 5x5 com quatro repetições. Paralelamente, foram fabricados quatro silos de características semelhantes aos demais com FAR sem a hidratação, denominados silos referência, e avaliada a peroxidação lipídica. Após a abertura (120 dias de ensilagem) foram avaliados o pH, acidez titulável (AT), índice de acidez (IA), índice de fungos (IF) e atividade de água (Aw). A temperatura (análise para verificar a estabilidade aeróbica) e o pH, pós abertura, foram determinados em 24, 48 e 120 horas após a abertura. Houve interações entre as variáveis para: pH na abertura, AT, IA e IF. Para a variável Aw não houve interação. A inclusão de 40% de FMI e 42,3% de água melhorou o pH da silagem na abertura, e a inclusão de 43,6% de água melhorou o pH 24 horas pós abertura. Após 48 horas de abertura as silagens estavam inapropriadas para o consumo, e a inclusão do milho acelerou a deterioração da massa ensilada após este período. Somente nos silos controles foi observado peroxidação lipídica.

Stability of high moisture corn silage and corn rehydrated / Estabilidade de silagens de grãos úmidos de milho e milho reidratado

This work was carried out to evaluate the fermentation characteristics and aerobic stability, regarding the conventional high moisture corn grain silage (Fortuna variety), the high moisture sweet corn grain silage and the high moisture rehydrated corn silage. Data were statistically analyzed as a 3x3 factorial arrangement in a completely randomized design, and the factors were three types of corn (Fortuna, sweet and rehydrated) and three inoculation treatments (without inoculum, bacterial inoculum and bacterial inoculum plus enzymes). The aerobic stability values were assessed, collecting the temperatures from the room dry bulb and from the silage thermometers, and the pH values, at 0, 24, 48, 72, 96, 168, 192, 216, 240 and 296 hours after aerobic exposition. Additionally, different mathematical models to estimate the mean pH values after opening were tested. Interactions were observed (P 0.05) between types of corns and inoculants for aerobic stability and pH at 72, 168 and 192 hours after opening. Inoculated sweet corn silages presented better aerobic stability after aerobic exposition compared to the other silages. The sweet corn silage presented lowest pH values at 48 hours after opening. The pH values at 168 hours of rehydrated corn silage treated with bacterial inoculum plus enzymes was more acid. Richards Equation (1959) was the best tool for the pH estimation when(AU)

Este trabalho foi realizado para avaliar as características fermentativas e a estabilidade aeróbica das silagens de grãos úmidos de milho: convencional, doce e reidratado. Foi utilizado um delineamento em esquema fatorial 3x3 com três tipos de milho (Fortuna, doce e reidratado) e três tratamentos de inoculação (sem inoculação; com inoculação bacteriana; inoculação bacteriana mais enzimas). Foram avaliados a estabilidade aeróbica (diferença entre temperatura do bulbo seco e temperatura das silagens) e os valores de pH com: 0, 24, 48, 72, 96, 168, 192, 216, 240 e 296 horas de exposição aeróbica. Adicionalmente, foram testados diferentes modelos matemáticos para estimar os valores médios de pH pós abertura. Houve interação (P 0,05) entre os tratamentos de inoculação e tipos de milho para a estabilidade aeróbica e para pH nas horas 72, 168 e 192 após a abertura dos silos. As silagens de milho doce inoculadas apresentaram melhor estabilidade aeróbica quando comparadas com as demais silagens. Para o pH às 48 horas a silagem de milho doce apresentou os menores valores de pH. O tratamento inoculação mais enzimas para a silagem de milho reidratado reduziu o pH 168. A equação de Richard (1959) foi a que melhor estimou os valores de pH para os tipos de inoculação e para o milho reidratado. Para as silagens de milho fortuna e doce o modelo proposto por Morgan et al. (1975) foi o que m(AU)

Stability of high moisture corn silage and corn rehydrated / Estabilidade de silagens de grãos úmidos de milho e milho reidratado

This work was carried out to evaluate the fermentation characteristics and aerobic stability, regarding the conventional high moisture corn grain silage (Fortuna variety), the high moisture sweet corn grain silage and the high moisture rehydrated corn silage. Data were statistically analyzed as a 3x3 factorial arrangement in a completely randomized design, and the factors were three types of corn (Fortuna, sweet and rehydrated) and three inoculation treatments (without inoculum, bacterial inoculum and bacterial inoculum plus enzymes). The aerobic stability values were assessed, collecting the temperatures from the room dry bulb and from the silage thermometers, and the pH values, at 0, 24, 48, 72, 96, 168, 192, 216, 240 and 296 hours after aerobic exposition. Additionally, different mathematical models to estimate the mean pH values after opening were tested. Interactions were observed (P 0.05) between types of corns and inoculants for aerobic stability and pH at 72, 168 and 192 hours after opening. Inoculated sweet corn silages presented better aerobic stability after aerobic exposition compared to the other silages. The sweet corn silage presented lowest pH values at 48 hours after opening. The pH values at 168 hours of rehydrated corn silage treated with bacterial inoculum plus enzymes was more acid. Richards Equation (1959) was the best tool for the pH estimation when

Este trabalho foi realizado para avaliar as características fermentativas e a estabilidade aeróbica das silagens de grãos úmidos de milho: convencional, doce e reidratado. Foi utilizado um delineamento em esquema fatorial 3x3 com três tipos de milho (Fortuna, doce e reidratado) e três tratamentos de inoculação (sem inoculação; com inoculação bacteriana; inoculação bacteriana mais enzimas). Foram avaliados a estabilidade aeróbica (diferença entre temperatura do bulbo seco e temperatura das silagens) e os valores de pH com: 0, 24, 48, 72, 96, 168, 192, 216, 240 e 296 horas de exposição aeróbica. Adicionalmente, foram testados diferentes modelos matemáticos para estimar os valores médios de pH pós abertura. Houve interação (P 0,05) entre os tratamentos de inoculação e tipos de milho para a estabilidade aeróbica e para pH nas horas 72, 168 e 192 após a abertura dos silos. As silagens de milho doce inoculadas apresentaram melhor estabilidade aeróbica quando comparadas com as demais silagens. Para o pH às 48 horas a silagem de milho doce apresentou os menores valores de pH. O tratamento inoculação mais enzimas para a silagem de milho reidratado reduziu o pH 168. A equação de Richard (1959) foi a que melhor estimou os valores de pH para os tipos de inoculação e para o milho reidratado. Para as silagens de milho fortuna e doce o modelo proposto por Morgan et al. (1975) foi o que m

Digestibility of wheat grain dual purpose, BRS Tarumã cultivar, produced in agroecological or conventional system for pigs / Digestibilidade do grão de trigo de duplo propósito, cultivar BRS Tarumã, produzido em sistema agroecológico ou convencional para suínos

Three experiments of the digestibility were carried out to determine the nutritional value, apparent digestibility and metabolizable coefficients and energy values for dual purpose wheat (BRS Tarumã) produced in agroecological or conventional system, for pigs in different stages (15, 45 and 75 kg of body weight -BW). Were used 15 barrows crossbreed of the commercial high-performance hybrids for each phase, allotted in three experimental groups, the first group received a diet specific to stage, called basaldiet (BD) the other groups received diet with 70% RR and 30% of dual-purpose wheat agroecological (Group 2) or conventional (Group 3). Were evaluated differences between the coefficients for each phase of the study. For the differences between phases were used descriptive analyzes. Production systems (conventional and agroecological) not affect the digestibility of wheat. The mean digestibility coefficients at 45 and 75 kg were higher. The digestible energy values were 3.25, 3.56 and 3.59 Mcal/kg for conventional and 3.14, 3.45 and 3.57 Mcal/kg for agroecological wheat for phases 15, 45 and 75 kg of BW, respectively. The use of wheat from the stage 45 kg showed better digestibility values, regardless of the production system.

Foram conduzidos três ensaios de digestibilidade para determinar o valor nutricional, os coeficientesde digestibilidade aparente e os teores de energia do trigo de duplo propósito (cultivar BRS Tarumã),produzido em sistema agroecológico ou convencional, para suínos em diferentes fases da criação (15,45 e 75 kg de peso vivo-PV). Foram utilizados 15 suínos machos castrados, híbridos comerciais dealto desempenho para cada fase, divididos em três grupos experimentais, o primeiro recebeu uma raçãoespecífica para a fase, denominada de ração referência (RR), os demais grupos receberam uma raçãoexperimental com 70% de RR e 30% de trigo de duplo propósito dos sistemas agroecológico (Grupo 2)ou convencional (Grupo 3). Foram testadas diferenças entre os coeficientes para cada fase do estudo. Paraas diferenças entre as fases foram realizadas análises descritivas das médias. Os sistemas de produção(convencional ou agroecológico) não alteraram os coeficientes de digestibilidade do trigo. As médiasdos coeficientes de digestibilidade aos 45 e 75 kg foram maiores. Os valores de energia digestívelforam de 3,25; 3,56 e 3,59 Mcal/kg para o trigo convencional e 3,14; 3,45 e 3,57 Mcal/kg para o trigoagroecológico, para as fases de 15, 45 e 75 kg de PV, respectivamente. A utilização do trigo a partir dafase de 45 kg apresentou melhores valores de digestibilidade, independente do sistema de produção.

Digestibility of wheat grain dual purpose, BRS Tarumã cultivar, produced in agroecological or conventional system for pigs / Digestibilidade do grão de trigo de duplo propósito, cultivar BRS Tarumã, produzido em sistema agroecológico ou convencional para suínos

Three experiments of the digestibility were carried out to determine the nutritional value, apparent digestibility and metabolizable coefficients and energy values for dual purpose wheat (BRS Tarumã) produced in agroecological or conventional system, for pigs in different stages (15, 45 and 75 kg of body weight -BW). Were used 15 barrows crossbreed of the commercial high-performance hybrids for each phase, allotted in three experimental groups, the first group received a diet specific to stage, called basaldiet (BD) the other groups received diet with 70% RR and 30% of dual-purpose wheat agroecological (Group 2) or conventional (Group 3). Were evaluated differences between the coefficients for each phase of the study. For the differences between phases were used descriptive analyzes. Production systems (conventional and agroecological) not affect the digestibility of wheat. The mean digestibility coefficients at 45 and 75 kg were higher. The digestible energy values were 3.25, 3.56 and 3.59 Mcal/kg for conventional and 3.14, 3.45 and 3.57 Mcal/kg for agroecological wheat for phases 15, 45 and 75 kg of BW, respectively. The use of wheat from the stage 45 kg showed better digestibility values, regardless of the production system.(AU)

Foram conduzidos três ensaios de digestibilidade para determinar o valor nutricional, os coeficientesde digestibilidade aparente e os teores de energia do trigo de duplo propósito (cultivar BRS Tarumã),produzido em sistema agroecológico ou convencional, para suínos em diferentes fases da criação (15,45 e 75 kg de peso vivo-PV). Foram utilizados 15 suínos machos castrados, híbridos comerciais dealto desempenho para cada fase, divididos em três grupos experimentais, o primeiro recebeu uma raçãoespecífica para a fase, denominada de ração referência (RR), os demais grupos receberam uma raçãoexperimental com 70% de RR e 30% de trigo de duplo propósito dos sistemas agroecológico (Grupo 2)ou convencional (Grupo 3). Foram testadas diferenças entre os coeficientes para cada fase do estudo. Paraas diferenças entre as fases foram realizadas análises descritivas das médias. Os sistemas de produção(convencional ou agroecológico) não alteraram os coeficientes de digestibilidade do trigo. As médiasdos coeficientes de digestibilidade aos 45 e 75 kg foram maiores. Os valores de energia digestívelforam de 3,25; 3,56 e 3,59 Mcal/kg para o trigo convencional e 3,14; 3,45 e 3,57 Mcal/kg para o trigoagroecológico, para as fases de 15, 45 e 75 kg de PV, respectivamente. A utilização do trigo a partir dafase de 45 kg apresentou melhores valores de digestibilidade, independente do sistema de produção.(AU)

Different sieving methods for determining the physical characteristics in ground corn / Different sieving methods for determining the physical characteristics in ground corn

We evaluated various sieving methods to estimate particle size (PS) and geometric standard deviation (GSD) of ground corn. The corn had been previously divided in six fractions and each one ground in a hammermill (1-, 2-, 3-, 4-, 5- or 12-mm sieves). The stacked sieving method, with prior drying at 105ºC without agitators was the reference. We evaluated eight sieving methods, distributed in a factorial design (2 x 2 x 2 x 6), consisting of the following treatments: i) with and without agitators (two 25-mm rubber spheres), ii) with and without previous drying, iii) with a nest of test sieves set in a stacked or reverse, and iv) employing six ground corn degrees, totaling 48 treatments (four replicates). There was a linear increase in PS estimation for methods without drying and stacking and quadratic increases for the others. Reverse, drying, and agitator methodologies gave better sieving of corn, and consequently gave the lowest PS and highest GSD. The results were more pronounced for high-intensity grinding (hammermill sieve with small apertures) in which the differences between the reference method with the drying and reverse methods were up to 210 µm. Reverse sieving combined with agitators allowed the greatest passage of corn particles through the test sieves and promoted better characterization of ground corn.

We evaluated various sieving methods to estimate particle size (PS) and geometric standard deviation (GSD) of ground corn. The corn had been previously divided in six fractions and each one ground in a hammermill (1-, 2-, 3-, 4-, 5- or 12-mm sieves). The stacked sieving method, with prior drying at 105ºC without agitators was the reference. We evaluated eight sieving methods, distributed in a factorial design (2 x 2 x 2 x 6), consisting of the following treatments: i) with and without agitators (two 25-mm rubber spheres), ii) with and without previous drying, iii) with a nest of test sieves set in a stacked or reverse, and iv) employing six ground corn degrees, totaling 48 treatments (four replicates). There was a linear increase in PS estimation for methods without drying and stacking and quadratic increases for the others. Reverse, drying, and agitator methodologies gave better sieving of corn, and consequently gave the lowest PS and highest GSD. The results were more pronounced for high-intensity grinding (hammermill sieve with small apertures) in which the differences between the reference method with the drying and reverse methods were up to 210 µm. Reverse sieving combined with agitators allowed the greatest passage of corn particles through the test sieves and promoted better characterization of ground corn.