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Introduction: High quality corn silage depends on factors such as corn type, stage of crop development at harvest time, fermentation time, in addition to use or not of inoculants. This study aimed to investigate the impact of maturity stage, bacterial inoculation, and storage time on fermentation, aerobic stability, and nutritional characteristics of flint corn silage and their implications for corn silage management. Methods: A flint corn hybrid was harvested very early, early, and medium (at 250, 300 and 350 g dry matter (DM)/kg as fed, respectively) and ensiled in mini-silos without (control) or with Lentilactobacillus buchneri CNCM I-4323 at 1 × 105 cfu/g for 120, 240 and 360 d to investigate how these factors interact with each other. Results and discussion: There was only a small increase (7 g/kg starch; p = 0.003) in starch digestibility (starch-D) in the silages stored for 360 d when compared to that stored for 240 d, but with no difference for 120 d. Despite the reduced starch-D (526 vs. 694 g/kg starch; p < 0.001), silages produced from medium harvest had higher (p < 0.001) starch content (317 vs. 137 g/kg DM) and higher amount of digestible starch (169 vs. 98.5 g/kg DM; p < 0.001) compared to very early harvest. The 2-way interactions (inoculation × storage time and maturity × storage time) showed that inoculation of corn silage with L. buchneri increased (p < 0.001) the aerobic stability, and that more mature crop silage had higher aerobic stability (140 h; p = 0.036) than the others (118 and 48.5 h for those silages from very early and early harvest). Conclusion: The storage for a longer time (>120 d) with the goal of increasing silage digestibility did not occur. Harvesting whole-crop flint corn with 300 to 350 g/kg DM is desirable to have higher DM yield and starch accumulation. Inoculation with L. buchneri is recommended to preserve the silage against aerobic deterioration. This study has shown the importance of harvesting flint corn at the right time, and the need for inoculation with L. buchneri to ensure greater yield, starch accumulation, and silage preservation, if 120 days of storage are not exceeded.

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The objectives of this experiment were to evaluate the effects of increasing levels of orange molasses in replacement of flint corn grain in high-concentrate diets on dry matter intake (DMI), average daily gain (ADG), and feed efficiency (FE) of feedlot lambs. Thirty male lambs without defined racial pattern (30.3 ± 5.3 kg of initial BW; mean ± SD) were used in a randomized complete block design with 10 blocks and 3 treatments. The treatments were defined by partial replacement of flint corn by orange molasses in the diet with 90% of concentrate and 10% of Cynodon spp. hay, as follows: 0OM-control diet without orange molasses; 20OM-20% of orange molasses replacing flint corn; and 40OM-40% of orange molasses replacing flint corn (DM basis). The experiment lasted 72 days divided into 3 subperiods, with 1 subperiod of 16 days and 2 subperiods of 28 days. Animals were weighed after a 16-h fast on days 1, 16, 44, and 72 of the experimental periods to determine the ADG and FE. The DMI, ADG, and FE showed an interaction between treatments and experimental periods. The DMI in the first period decreased linearly (P < 0.01); in the third period, there was no effect of treatments (P > 0.05) on DMI. The ADG decreased linearly (P < 0.01) in the first period as the orange molasses increased. Otherwise, in the third period, ADG increased linearly (P = 0.05) as flint corn was replacement by orange molasses. The FE showed an interaction between treatment and period (P = 0.09). The first period had a decreased linear effect; in the third period, there was a trend (P = 0.07) of increased linear effect. There was no difference between the diets regarding the final BW of the lambs. In conclusion, the orange molasses can replace up to 40% of flint corn in diets for feedlot lambs without affecting final BW. However, it is important to consider the adaptation time proved to be very important for better use of orange molasses as a source of energy in diets for lambs.

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BACKGROUND: Mycotoxin monitoring in cereal grains has great importance in the food and feed industries. This study evaluated mycotoxin contamination in corns with different endosperm textures in 2 years of cultivation. Samples of dent, semi-dent, flint and semi-flint corns from field experiments were analyzed by high-performance liquid chromatography coupled with tandem mass spectrometry (HPLC-MS/MS). RESULTS: Occurrences of fumonisins B1 (FB1 ) and B2 (FB2 ) in 2020 were 45.72% (mean 270 µg kg-1 ) and 35.89% (94.97 µg kg-1 ), respectively, and 68.98% (446 µg kg-1 ) and 45.83% (152 µg kg-1 ) in 2021. Occurrence of aflatoxin B1 was 11.96% (0.16 µg kg-1 ) in 2020 and 11.11% (0.13 µg kg-1 ) in 2021. In 2020, deoxynivalenol (DON) and zearalenona (ZEA) presented occurrences of 1.28% and 1.70%, with means of 4.08 and 2.45 µg kg-1 , respectively. In 2021, results were 8.33% (31.00 µg kg-1 ) for DON and 8.79% (4.38 µg kg-1 ) for ZEA. Citrinin, diacetoxyscirpenol and fusarenon-X did not occur in 2020 but presented 1.66%, 0.83%, and 2.50% positive rates in 2021, respectively. In 2020, flint corn presented the lowest concentration of FB1 whereas dent corn presented the highest concentration of FB1 and FB2 (P < 0.05). In 2021, dent corn presented the highest means of FB1 , FB2 and diacetoxyscirpenol (P < 0.05). Dent and semi-dent presented the highest concentration of nivalenol (P < 0.05). CONCLUSION: The endosperm texture influenced mycotoxin contamination in corn grains, especially FB1 and FB2 , which had the highest concentration in dent corn in the 2 years of this study. © 2023 Society of Chemical Industry.

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The objective of this study was to evaluate the effects of corn hybrid and processing methods on intake and digestibility of nutrients, rumen fermentation and blood metabolites of steers fed no-forage finishing diets. Four ruminally fistulated Nellore castrated steers (502 ± 15 kg initial body weight) were distributed in a 4 × 4 Latin square design with a 2 × 2 factorial arrangement consisting of two corn hybrids (semi-dent and flint) and two processing methods (dry milled and high moisture grain). Interactions of hybrid and processing methods were observed on intake of dry matter (DM), organic matter (OM) and crude protein (CP), as well as on digestibility of DM and CP, rumen pH and ammonia nitrogen (N-NH3 ). There was no interaction between hybrid and processing for the volatile fatty acids (VFA) total, acetate (C2), propionate (C3), isobutyric (iC4) and valeric (nC5) concentrations. VFA total concentration shown an average of 103.4 mmol/L. The C2 and C3 concentrations had no effect of the hybrid or processing with averages of 58.7 mmol/L for C2, and 31.3 mmol/l for C3. There was an effect of the processing method on starch consumption and fecal pH, the highest values were observed in grains with high moisture content. Starch digestibility was 0.89 g/g in dry milled and 0.96 g/g in high moisture corn. The greatest digestibility of starch in high moisture corn, irrespective of the corn hybrid, provided evidence of an increase in the energy supply, which may improve the feed efficiency and growth performance of cattle fed no-roughage finishing diets.

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BACKGROUND: Protein percentage and kernel weight affect the endosperm hardness of maize grains. However, changes in starch composition could also modify kernel hardness, which is often predicted through milling ratio. The objective of this work was to evaluate the relationship between changes in starch composition and endosperm hardness, and to assess the effects of protein content and kernel weight on that relationship. For this, we used information obtained from three temperate hybrids in multi-environmental experiments, as well as experiments conducted under controlled conditions designed to modify starch composition. Milling ratio was determined as maize kernel hardness predictor in both experiments and it was correlated with grain weight and grain composition. RESULTS: In both experiments, milling ratio presented a significant Spearman correlation coefficient with amylose/starch ratio. Milling ratio was significantly related to the amylose/starch ratio using a simple fit with datasets from different experiments and hybrids. Increases in amylose/starch ratio were associated with increases in milling ratio. CONCLUSION: Starch composition was related to milling ratio variations among hybrids of different aptitude for dry milling through different environments, regardless of protein content. Thus, increases in the amylose/starch ratio were related to increases in the milling ratio. © 2022 Society of Chemical Industry.

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Our objective was to examine the effects of processing, moisture, and anaerobic storage length of reconstituted corn grain (RCG) on the fermentation profile, geometric mean particle size (GMPS), and ruminal dry matter disappearance (DMD). Dry corn kernels were ground (hammer mill, 5-mm screen) or rolled, then rehydrated to 30%, 35%, or 40% moisture, and stored for 0, 14, 30, 60, 90, 120, or 180 d in laboratory silos. Rolled corn had an increased GMPS compared with ground corn (2.24 and 1.13 mm, respectively, at ensiling). However, there was a trend for an interaction between processing and moisture concentration to affect particle size, with GMPS increasing with increased moisture concentration, especially in ground corn. Longer storage periods also slightly increased GMPS. Processing, moisture, and storage length interacted to affect the fermentation pattern (two- or three-way interactions). Overall, pH decreased, whereas lactic acid, acetic acid, ethanol, and NH3-N increased with storage length. RCG with 30% moisture had less lactic acid than corn with 35% and 40% moisture, indicating that fermentation might have been curtailed and also due to the clostridial fermentation that converts lactic acid to butyric acid. Ensiling reconstituted ground corn with 30% of moisture led to greater concentrations of ethanol and butyric acid, resulting in greater DM loss than grain rehydrated to 35% or 40% of moisture. Ammonia-N and in situ ruminal DMD were highest for reconstituted ground corn with 35% or 40% of moisture, mainly after 60 d of storage. Therefore, longer storage periods and greater moisture contents did not offset the negative effect of greater particle size on the in situ ruminal DMD of rolled RCG. Nonetheless, RCG should be ensiled with more than 30% moisture and stored for at least 2 mo to improve the ruminal DMD and reduce the formation of ethanol and butyric acid.

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A new prepared catalyst, 12-molybdophosphoric acid (HPMo) anchored to the mesoporous aluminosilicate AlSiM, synthesized from Amazon kaolin, was characterized and used as a heterogeneous acid catalyst for the production of eugenyl acetate by acetylation of eugenol with acetic anhydride. The effect of various reaction parameters, such as catalyst concentration, eugenol/acetic anhydride molar ratio, temperature and reaction time, was studied to optimize the conditions of maximum conversion of eugenol. The kinetics studies showed that in eugenol acetylation, the substrate concentration follows a first order kinetics. The results of activation energy was 19.96 kJ mol-1 for HPMo anchored to AlSiM. The reuse of the catalyst was also studied and there was no loss of catalytic activity after four cycles of use (from 99.9% in the first cycle to 90% in the fifth cycle was confirmed), and an excellent stability of the material was observed. Based on catalytic and kinetic studies, HPMo anchored to AlSiM is considered an excellent catalyst.

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Con el objetivo de determinar la utilidad del índice de Flint como predictor de complicaciones postoperatorias en trauma de colon en pacientes que ingresaron al Servicio de Cirugía General del Hospital Central Universitario Dr. Antonio María Pineda, se realizó un estudio descriptivo transversal que incluyó 77 pacientes cuya edad promedio fue de 28,2 ± 10,8 años con predominio del sexo masculino (98,7%). Los resultados indican que el mecanismo de producción del trauma más frecuente fue por arma de fuego carga única (67,5%); el segmento más afectado fue colon sigmoide (32,4%) y transverso (31,1%); 74% de los pacientes presentaron una única lesión en colon y los órganos con lesiones asociadas más comunes fueron intestino delgado (59,7%), hígado (19,4%) y riñón (12,9%). Se encontró perforación en el 54,5% de los casos, contaminación moderada (42,8%), presencia de lesiones asociadas (85,7%), situación hemodinámica discreta (59,7%) y retardo en el tratamiento < 6 horas (45,4%). Según el índice de Flint, 51,9% de los pacientes mostraron una gravedad grado III, 40,2% grado II y 7,7% grado I. El tratamiento fue quirúrgico en 88,3% de los casos y la técnica quirúrgica más utilizada fue rafia primaria (55,8%), seguida de resección/anastomosis (27,9%) y resección/colostomía (25%). En conclusión, la escala de Flint es una herramienta de predicción para complicaciones postoperatorias en los pacientes con traumatismo de colon(AU)

In order to determine the usefulness of the Flint Index as a predictor of postoperative complications in colon trauma in patients admitted to the Servicio de Cirugía General of the Hospital Universitario Dr. Antonio María Pineda, we conducted a cross-sectional descriptive study with 77 patients with an average age of 28.2 ± 10.8 years and predominance of male sex (98.7%). The most frequent mechanism of trauma was by single shot firearm (67.5%); the most affected segment was sigmoid colon (32.4%) and transverse (31.1%); 74% of patients had only one lesion in colon and the most common associated lesions were localized in small intestine (59.7%), liver (19.4%) and kidney (12.9%). According to the severity of trauma, perforation was found in 54.5% of cases, moderate contamination (42.8%), presence of associated lesions (85.7%), discrete hemodynamic situation (59.7%) and delay in treatment of less than 6 hours (45.4%). According to the Flint index, 51.9% of patients had a severity grade III, 40.2% grade II and 7.7% grade I. The treatment was surgical in 88.3% of cases and the most used surgical technique was primary raffia (55.8%), followed by resection/anastomosis (27.9%) and resection/colostomy (25%). In conclusion, the Flint scale is a predictive tool for postoperative complications in patients with colonic trauma(AU)

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OBJECTIVE: We evaluated the increases in blood lead levels (BLLs) observed in young children in Flint, Michigan, during their exposure to corrosive Flint River water during the years 2014 and 2015 and compared their BLLs to those of Flint children measured during the years 2006-2013 and 2016. STUDY DESIGN: This was a retrospective study design using BLLs extracted from databases from 2006 to 2016. We analyzed a population sample of 15 817 BLLs from children aged ≤5 years with potential exposure to contaminated Flint River water. Percentages of BLLs ≥5.0 µg/dL and geometric mean (GM) BLLs were analyzed over time. RESULTS: A significant decline in the percentages of BLLs ≥5.0 µg/dL from 11.8% in 2006 to 3.2% in 2016 was observed (P < .001). GM ± SE BLLs decreased from 2.33 ± 0.04 µg/dL in 2006 to 1.15 ± 0.02 µg/dL in 2016 (P < .001). GM BLLs increased twice: from 1.75 ± 0.03 µg/dL to 1.87 ± 0.03 µg/dL (2010-2011) and from 1.19 ± 0.02 µg/dL to 1.30 ± 0.02 µg/dL (2014-2015). Overall, from 2006 to 2016, there was a 72.9% decrease in the percentage of children with BLLs ≥5.0 µg/dL and a 50.6% decrease in GM BLLs. CONCLUSION: These findings suggest that the 11 year trend of annual decreases in BLLs in children in Flint, Michigan, reversed to a degree consistent with random variation from 2010 to 2011, and again during the exposure to Flint River water in 2014-2015. Historically, public health efforts to reduce BLLs of young children in Flint have been effective over the 11-year period studied.

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OBJECTIVES: To determine whether there are substantial differences by state between 2 large datasets in the proportion of children with elevated blood lead levels (BLLs); to identify states in which the percentage of elevated BLLs is high in either or both datasets; and to compare the percentage of elevated BLLs in individual states with those of children living in Flint, Michigan, during the months when these children were exposed to lead-contaminated drinking water. STUDY DESIGN: Tables of BLLs for individual states from the Quest Diagnostics and the Centers for Disease Control and Prevention datasets for 2014-2015, containing more than 3 million BLLs of young children?

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Avaliou-se o desempenho de vacas leiteiras que consumiram polpa cítrica e dois teores dietéticos de silagem de grão úmido de milho. Os tratamentos foram: milho de textura dura ou milho de textura macia ensilado na linha negra, em fatorial com 9% ou 18% de milho na dieta. O teor de polpa cítrica na dieta foi de 16,2% ou 25,6%, com alto e baixo milho, respectivamente. Doze vacas receberam os tratamentos em quadrados latinos 4x4. A produção diária de leite foi 27,9kg no milho duro e 28,8 no macio (P=0,19). Alto milho diminuiu o teor de gordura do leite de 3,38 para 3,26% (P=0,04) e aumentou o teor de proteína de 2,99 para 3,03% (P=0,05) e a eficiência alimentar de 1,50 para 1,57kg de leite/kg de consumo (P=0,03). Aumento no teor de milho induziu maior queda no pH ruminal na dieta com milho macio do que na dieta com milho duro (P=0,05 para a interação textura versus teor de milho). O milho macio aumentou o consumo diário de matéria orgânica digestível de 11,7 para 12,3kg (P=0,05). Os parâmetros digestivos sugerem que a ensilagem não eliminou totalmente o efeito da textura do endosperma sobre a digestibilidade do milho.(AU)

Lactating cow performance on diets containing citrus pulp and two levels of high moisture corn silage was evaluated. Treatments were: hard texture corn or soft texture corn ensiled at the black layer, with a 9% or 18% factorial corn in the diet. Dietary citrus pulp content was 16.2% or 25.6%, for high and low corn, respectively. Twelve cows received the treatments in 4x4 Latin Squares. Daily milk yield was 27.9kg for hard corn and 28.8 for soft (P=0.19). High corn decreased milk fat content from 3.38 to 3.26% (P=0.04), and increased protein content from 2.99 to 3.03% (P=0.05) and feed efficiency from 1.50 to 1.57kg of milk/kg of intake (P=0.03). The increase of corn content generated a greater decrease in ruminal pH in the soft corn diet than in the hard corn diet (P=0.05 for the interaction of texture versus corn content). Soft corn increased the daily intake of digestible organic matter from 11.7 to 12.3kg (P=0.05). Digestive parameters suggest that ensilaging did not totally eliminate the endosperm texture effect on corn digestibility.(AU)

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Avaliou-se o desempenho de vacas leiteiras que consumiram polpa cítrica e dois teores dietéticos de silagem de grão úmido de milho. Os tratamentos foram: milho de textura dura ou milho de textura macia ensilado na linha negra, em fatorial com 9% ou 18% de milho na dieta. O teor de polpa cítrica na dieta foi de 16,2% ou 25,6%, com alto e baixo milho, respectivamente. Doze vacas receberam os tratamentos em quadrados latinos 4x4. A produção diária de leite foi 27,9kg no milho duro e 28,8 no macio (P=0,19). Alto milho diminuiu o teor de gordura do leite de 3,38 para 3,26% (P=0,04) e aumentou o teor de proteína de 2,99 para 3,03% (P=0,05) e a eficiência alimentar de 1,50 para 1,57kg de leite/kg de consumo (P=0,03). Aumento no teor de milho induziu maior queda no pH ruminal na dieta com milho macio do que na dieta com milho duro (P=0,05 para a interação textura versus teor de milho). O milho macio aumentou o consumo diário de matéria orgânica digestível de 11,7 para 12,3kg (P=0,05). Os parâmetros digestivos sugerem que a ensilagem não eliminou totalmente o efeito da textura do endosperma sobre a digestibilidade do milho.

Lactating cow performance on diets containing citrus pulp and two levels of high moisture corn silage was evaluated. Treatments were: hard texture corn or soft texture corn ensiled at the black layer, with a 9% or 18% factorial corn in the diet. Dietary citrus pulp content was 16.2% or 25.6%, for high and low corn, respectively. Twelve cows received the treatments in 4x4 Latin Squares. Daily milk yield was 27.9kg for hard corn and 28.8 for soft (P=0.19). High corn decreased milk fat content from 3.38 to 3.26% (P=0.04), and increased protein content from 2.99 to 3.03% (P=0.05) and feed efficiency from 1.50 to 1.57kg of milk/kg of intake (P=0.03). The increase of corn content generated a greater decrease in ruminal pH in the soft corn diet than in the hard corn diet (P=0.05 for the interaction of texture versus corn content). Soft corn increased the daily intake of digestible organic matter from 11.7 to 12.3kg (P=0.05). Digestive parameters suggest that ensilaging did not totally eliminate the endosperm texture effect on corn digestibility.

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We determined the values of apparent metabolizable (AME), apparent corrected (AMEn), true (TME) and true corrected (TMEn) energy of six corn hybrids for broiler chickens in phases 1-7, 8-14, 15-21, 22-28, 29-35 and 36-42 day-old birds, using the substitution method (40 percent) of reference diet with the test ingredient. Ross-308 male chicks (1,134) were allotted to metabolism cages and the number of birds per experimental unit was adjusted to suit each bird's density stage in the cage, using six replicates. Simultaneously, birds continue to fast for the determination of metabolic and endogenous losses for each study phase. The birds received water and food ad libitum during the experimental period. The birds were maintained in metabolism cages for seven days, four days for adaptation to the cage and food, and three days for excreta collection. The corn energy values were significantly lower only in the pre-initial phase (1-7 days). Thus, broiler feed formulations of AMEn values for corn of 3563 kcal/kg DM for 1 to 7 days and 3778 kcal/kg DM from 7-day-old birds are recommended.The agronomic characteristics of the corn had no influence on the birds energy levels.

Foram determinados os valores de energia metabolizável aparente (EMA), aparente corrigida (EMAn), verdadeira (EMV) e verdadeira corrigida (EMVn) de seis milhos híbridos para frangos de corte nas fases de 1 a 7, 8 a 14, 15 a 21, 22 a 28, 29 a 35 e 36 a 42 dias de idade das aves, usando o método de substituição (40 por cento) da ração referência pelo ingrediente em teste. Pintos machos Ross-308 (1.134) foram distribuídos em gaiolas de metabolismo, sendo o número de aves por parcela, ajustado em cada fase para adequação da densidade de aves na gaiola, sendo utilizadas 6 repetições por tratamento. Simultaneamente, foram mantidas aves em jejum para a determinação das perdas endógenas e metabólicas para cada fase do estudo. As aves receberam água e ração à vontade durante todo período experimental. As aves foram mantidas nas gaiolas de metabolismo durante sete dias, sendo quatro dias para adaptação à gaiola e à alimentação e três dias para a coleta de excretas. Os valores energéticos dos milhos foram significativamente inferiores somente na fase pré-inicial (1 a 7 dias) em relação às demais. Assim, recomenda-se usar nas formulações os valores de EMAn do milho de 3563/kg MS de 1 a 7 dias e de 3778 kcal/kg MS a partir 7 dias de idade das aves As características agronômicas dos milhos não influíram nos seus teores de energia.

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The whole corn plant silage practice and the seek for materials of better quality results in various genotypes with specific characteristics wich when it is combined with mechanical processing, becomes an important research topic. The objective of this study was the evaluation of two mechanical processing at two different maturity ages of flint and dent corn hybrids on ruminal degradability of: dry matter (DM), neutral detergent fiber (NDF), crude protein (CP), and starch by the technique of "in situ micro bag". It were used three ruminal cannulated Holstein cows with 520kg of mean live weight. The experiment was carried out in a completely randomized design, using repeated mesurementst over time. The mechanical processing, maturity stages and incubation time were significant (P 0.05) for all the analyzed variables. There was an interaction among hybrid*time for CP. The interaction maturity stages*time of incubation was significant for DM, NDF, CP with effect of hybrid corn for starch. Also, the interaction among hybrid*mechanical processing*incubation time for DM and NDF and incubation time*maturity stages*mechanical processing for DM were significant. The greatest effective degradability (ED) was for the dent hybrid processed harvest at point 1 and it wasnt significant statistically different from the others processed treatments, but 36% greater than the not processed tre

A ensilagem da planta inteira de milho e a procura por materiais de melhor qualidade vêm favorecendo o surgimento de inúmeros genótipos com características específicas que aliados ao uso do processamento mecânico são importantes linhas de pesquisa. O objetivo deste trabalho foi avaliar o efeito do esmagamento das plantas de milho após a picagem, para ser ensilada em dois estádios de colheita de híbridos de duas texturas sobre a degradabilidade ruminal da matéria seca (MS), fibra em detergente neutro (FDN), proteína bruta (PB) e amido por meio da técnica "in situ macro bag". Utilizaram-se três vacas holandesas, com peso vivo médio de 520kg, providas de cânula ruminal permanente. O experimento foi feito no delineamento inteiramente casualizado, com medidas repetidas no tempo. Foi significativo (P 0,05) o efeito do processamento, estádio de colheita e tempos de incubação para todas as variáveis analisadas. Houve interação de híbrido*tempo para a PB. A interação entre estádio*tempo foi significativa para a MS, FDN e PB, com efeito de híbrido para o amido. Houve interação entre hibrido*processamento*tempo para MS e FDN e entre tempo*estádio*processamento para MS. A degradabilidade efetiva (DE) da MS mostrou-se numericamente superior para o híbrido dentado esmagado no estádio 1, sendo que nos tratamentos com esmagamento, os resultados foram de até 36%. Para PB, o esmagamento foi e

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The whole corn plant silage practice and the seek for materials of better quality results in various genotypes with specific characteristics wich when it is combined with mechanical processing, becomes an important research topic. The objective of this study was the evaluation of two mechanical processing at two different maturity ages of flint and dent corn hybrids on ruminal degradability of: dry matter (DM), neutral detergent fiber (NDF), crude protein (CP), and starch by the technique of "in situ micro bag". It were used three ruminal cannulated Holstein cows with 520kg of mean live weight. The experiment was carried out in a completely randomized design, using repeated mesurementst over time. The mechanical processing, maturity stages and incubation time were significant (P 0.05) for all the analyzed variables. There was an interaction among hybrid*time for CP. The interaction maturity stages*time of incubation was significant for DM, NDF, CP with effect of hybrid corn for starch. Also, the interaction among hybrid*mechanical processing*incubation time for DM and NDF and incubation time*maturity stages*mechanical processing for DM were significant. The greatest effective degradability (ED) was for the dent hybrid processed harvest at point 1 and it wasnt significant statistically different from the others processed treatments, but 36% greater than the not processed tre

A ensilagem da planta inteira de milho e a procura por materiais de melhor qualidade vêm favorecendo o surgimento de inúmeros genótipos com características específicas que aliados ao uso do processamento mecânico são importantes linhas de pesquisa. O objetivo deste trabalho foi avaliar o efeito do esmagamento das plantas de milho após a picagem, para ser ensilada em dois estádios de colheita de híbridos de duas texturas sobre a degradabilidade ruminal da matéria seca (MS), fibra em detergente neutro (FDN), proteína bruta (PB) e amido por meio da técnica "in situ macro bag". Utilizaram-se três vacas holandesas, com peso vivo médio de 520kg, providas de cânula ruminal permanente. O experimento foi feito no delineamento inteiramente casualizado, com medidas repetidas no tempo. Foi significativo (P 0,05) o efeito do processamento, estádio de colheita e tempos de incubação para todas as variáveis analisadas. Houve interação de híbrido*tempo para a PB. A interação entre estádio*tempo foi significativa para a MS, FDN e PB, com efeito de híbrido para o amido. Houve interação entre hibrido*processamento*tempo para MS e FDN e entre tempo*estádio*processamento para MS. A degradabilidade efetiva (DE) da MS mostrou-se numericamente superior para o híbrido dentado esmagado no estádio 1, sendo que nos tratamentos com esmagamento, os resultados foram de até 36%. Para PB, o esmagamento foi e

RESUMO

The predominance of vitreous endosperm in hard texture flint corn (Zea mays L.) can decrease ruminal starch digestion comparatively to the farinaceous endosperm of dent corn, reducing energy content of the grain. The objective of this experiment was to evaluate the effects of texture and maturity stage on ruminal degradability of corn grain. Two dent and two flint hybrids were harvested at the early dent, half milk line, and black layer stages. The proportion of vitreous endosperm (vitreousness) in dent hybrids was 44.3%, while in flint it was 67.0%. There was a linear increase in vitreousness with advancing maturity. Flint hybrids at the early dent stage were more vitreous than dent at the black layer stage. The increase in vitreousness per maturation day was greater for flint hybrids. Grains were incubated in situ in the rumen of 6 cows. The 24-hour ruminal dry matter degradation was 63.3% for dent corn and 52.4% for flint corn. The 72-hour incubation residues of dent and flint hybrids were 7.6% and 15.6%, respectively. Ruminal degradability was similar between hybrids at the early dent and half milk line stages. There was a marked texture effect on ruminal degradability at the black layer stage (quadratic effect of maturity stage and interaction between texture and maturity stage). Use of dent hybrids, compared to flint hybrids, may result in smaller relative reduction in ruminal starch digestion in situations of late grain harvesting.

A predominância de endosperma vítreo em milho (Zea mays L.) flint de textura dura pode deprimir a digestão ruminal do amido comparativamente ao endosperma farináceo de milho dentado, reduzindo o conteúdo energético do grão. O objetivo deste experimento foi avaliar os efeitos da textura e do estádio de maturidade sobre a degradabilidade ruminal de grãos de milho. Dois híbridos dentados e dois duros foram colhidos nos estádios dentado inicial, metade da linha do leite e linha preta. A proporção de endosperma vítreo (vitreosidade) dos híbridos dentados foi 44,3% e a dos duros foi 67,0%. Ocorreu aumento linear na vitreosidade com o avançar da maturidade. Os híbridos duros no estádio dentado inicial foram mais vítreos que os dentados no estádio linha preta. O aumento na vitreosidade por dia de maturação foi maior nos híbridos duros. Os grãos foram incubados in situ no rúmen de 6 vacas. A degradação ruminal da matéria seca em 24 horas foi 63,3% nos grãos dentados e 52,4% nos duros. O resíduo após 72 horas de incubação de híbridos dentados e duros foram 7,6% e 15,6%, respectivamente. A degradabilidade ruminal dos híbridos foi similar nos estádios dentado inicial e metade da linha do leite. O efeito da textura sobre a degradabilidade ruminal foi acentuado no estádio linha preta (P 0,01 para o efeito quadrático de estádio de maturação e para a interação entre textura e estádio de maturação). A utilização de híbridos dentados, comparativamente a híbridos duros, pode resultar em menor queda relativa na digestão ruminal do amido em situações de colheita tardia dos grãos.

RESUMO

The predominance of vitreous endosperm in hard texture flint corn (Zea mays L.) can decrease ruminal starch digestion comparatively to the farinaceous endosperm of dent corn, reducing energy content of the grain. The objective of this experiment was to evaluate the effects of texture and maturity stage on ruminal degradability of corn grain. Two dent and two flint hybrids were harvested at the early dent, half milk line, and black layer stages. The proportion of vitreous endosperm (vitreousness) in dent hybrids was 44.3%, while in flint it was 67.0%. There was a linear increase in vitreousness with advancing maturity. Flint hybrids at the early dent stage were more vitreous than dent at the black layer stage. The increase in vitreousness per maturation day was greater for flint hybrids. Grains were incubated in situ in the rumen of 6 cows. The 24-hour ruminal dry matter degradation was 63.3% for dent corn and 52.4% for flint corn. The 72-hour incubation residues of dent and flint hybrids were 7.6% and 15.6%, respectively. Ruminal degradability was similar between hybrids at the early dent and half milk line stages. There was a marked texture effect on ruminal degradability at the black layer stage (quadratic effect of maturity stage and interaction between texture and maturity stage). Use of dent hybrids, compared to flint hybrids, may result in smaller relative reduction in ruminal starch digestion in situations of late grain harvesting.

A predominância de endosperma vítreo em milho (Zea mays L.) flint de textura dura pode deprimir a digestão ruminal do amido comparativamente ao endosperma farináceo de milho dentado, reduzindo o conteúdo energético do grão. O objetivo deste experimento foi avaliar os efeitos da textura e do estádio de maturidade sobre a degradabilidade ruminal de grãos de milho. Dois híbridos dentados e dois duros foram colhidos nos estádios dentado inicial, metade da linha do leite e linha preta. A proporção de endosperma vítreo (vitreosidade) dos híbridos dentados foi 44,3% e a dos duros foi 67,0%. Ocorreu aumento linear na vitreosidade com o avançar da maturidade. Os híbridos duros no estádio dentado inicial foram mais vítreos que os dentados no estádio linha preta. O aumento na vitreosidade por dia de maturação foi maior nos híbridos duros. Os grãos foram incubados in situ no rúmen de 6 vacas. A degradação ruminal da matéria seca em 24 horas foi 63,3% nos grãos dentados e 52,4% nos duros. O resíduo após 72 horas de incubação de híbridos dentados e duros foram 7,6% e 15,6%, respectivamente. A degradabilidade ruminal dos híbridos foi similar nos estádios dentado inicial e metade da linha do leite. O efeito da textura sobre a degradabilidade ruminal foi acentuado no estádio linha preta (P 0,01 para o efeito quadrático de estádio de maturação e para a interação entre textura e estádio de maturação). A utilização de híbridos dentados, comparativamente a híbridos duros, pode resultar em menor queda relativa na digestão ruminal do amido em situações de colheita tardia dos grãos.

RESUMO

Corn cultivated in Brazil is predominantly of hard texture, and more propense to decreased starch digestibility under late harvesting situations than dent hybrids. This work tested the utilization of dent corn as a way of extending the ensilage period without reducing animal performance, and evaluated the potential of sugarcane as a forage for high-producing dairy cows. Nine lactating Holstein cows were allocated to three 3 ' 3 latin squares and were fed 200 g of forage neutral detergent fiber per kg of dry matter as either hard texture corn ensiled at the half milk line stage of maturity, soft texture corn ensiled at the black layer stage, or sugarcane. There were no detectable differences between corn hybrids with regard to milk yield (34.2 vs 34.6 kg d-1) and composition, dry matter intake (23.0 vs 23.2 kg d-1) and total tract apparent digestibility of nutrients. Sugarcane decreased feed intake (21.5 kg d-1) and milk yield (31.9 kg d-1). Organic matter digestibility, chewing activity and rumen pH did not differ among treatments. Sugarcane seems to be a viable option to feed groups of Holstein cows during lactation stages in which nutrient demand is not at a maximum. The performance of dairy cows fed dent corn ensiled at the black layer stage of maturity was similar to the performance of cows fed flint corn ensiled at the half milk line stage.

O milho cultivado no Brasil é predominantemente de textura dura, e mais propenso a redução na digestibilidade do amido em situação de colheita tardia que híbridos dentados. Este trabalho testou a utilização de milho dentado como maneira de ampliar o período de ensilagem sem reduzir o desempenho animal e avaliou o potencial da cana-de-açúcar em dietas para vacas leiteiras de alta produção. Nove vacas Holandesas foram alocadas em três quadrados latinos 3 ' 3 e alimentadas com 200 g de fibra em detergente neutro oriunda de forragem por kg de matéria seca como milho de textura dura ensilado no estádio de maturação "metade da linha do leite", milho de textura macia no estádio "linha negra" ou cana-de-açúcar. Não foi detectada diferença entre híbridos de milho na produção (34,2 vs 34,6 kg d-1) e na composição do leite, no consumo de matéria seca (23,0 vs 23,2 kg d-1) e na digestibilidade aparente de nutrientes no trato digestivo total. A cana-de-açúcar deprimiu o consumo (21,5 kg d-1) e a produção de leite (31,9 kg d-1). A digestibilidade da matéria orgânica, a atividade mastigatória e o pH ruminal não foram diferentes entre tratamentos. A cana-de-açúcar parece ser uma opção para alimentar grupos de vacas Holandesas durante fases da lactação na qual a demanda nutricional não é a máxima. O desempenho de vacas leiteiras alimentadas com milho dentado ensilado em estádio de maturação "linha negra" foi similar ao de vacas alimentadas com milho duro ensilado no estádio "metade da linha do leite".

RESUMO

Corn cultivated in Brazil is predominantly of hard texture, and more propense to decreased starch digestibility under late harvesting situations than dent hybrids. This work tested the utilization of dent corn as a way of extending the ensilage period without reducing animal performance, and evaluated the potential of sugarcane as a forage for high-producing dairy cows. Nine lactating Holstein cows were allocated to three 3 ' 3 latin squares and were fed 200 g of forage neutral detergent fiber per kg of dry matter as either hard texture corn ensiled at the half milk line stage of maturity, soft texture corn ensiled at the black layer stage, or sugarcane. There were no detectable differences between corn hybrids with regard to milk yield (34.2 vs 34.6 kg d-1) and composition, dry matter intake (23.0 vs 23.2 kg d-1) and total tract apparent digestibility of nutrients. Sugarcane decreased feed intake (21.5 kg d-1) and milk yield (31.9 kg d-1). Organic matter digestibility, chewing activity and rumen pH did not differ among treatments. Sugarcane seems to be a viable option to feed groups of Holstein cows during lactation stages in which nutrient demand is not at a maximum. The performance of dairy cows fed dent corn ensiled at the black layer stage of maturity was similar to the performance of cows fed flint corn ensiled at the half milk line stage.

O milho cultivado no Brasil é predominantemente de textura dura, e mais propenso a redução na digestibilidade do amido em situação de colheita tardia que híbridos dentados. Este trabalho testou a utilização de milho dentado como maneira de ampliar o período de ensilagem sem reduzir o desempenho animal e avaliou o potencial da cana-de-açúcar em dietas para vacas leiteiras de alta produção. Nove vacas Holandesas foram alocadas em três quadrados latinos 3 ' 3 e alimentadas com 200 g de fibra em detergente neutro oriunda de forragem por kg de matéria seca como milho de textura dura ensilado no estádio de maturação "metade da linha do leite", milho de textura macia no estádio "linha negra" ou cana-de-açúcar. Não foi detectada diferença entre híbridos de milho na produção (34,2 vs 34,6 kg d-1) e na composição do leite, no consumo de matéria seca (23,0 vs 23,2 kg d-1) e na digestibilidade aparente de nutrientes no trato digestivo total. A cana-de-açúcar deprimiu o consumo (21,5 kg d-1) e a produção de leite (31,9 kg d-1). A digestibilidade da matéria orgânica, a atividade mastigatória e o pH ruminal não foram diferentes entre tratamentos. A cana-de-açúcar parece ser uma opção para alimentar grupos de vacas Holandesas durante fases da lactação na qual a demanda nutricional não é a máxima. O desempenho de vacas leiteiras alimentadas com milho dentado ensilado em estádio de maturação "linha negra" foi similar ao de vacas alimentadas com milho duro ensilado no estádio "metade da linha do leite".