ABSTRACT. The objective was to evaluate the ruminal disappearance rate of dry matter and NDF of black oat haylage subjected to mechanical and chemical dehydration and six wilting periods in the field, as follows: 0, 3, 6, 9, 12 and 15 days. Forage haylages were ensiled and stored in PVC mini-silos for 60 days until opening for in situ evaluations. The pre-set ruminal incubation times were: 0, 6, 12, 24, 36 and 48 hours. Regardless of the dehydration time, forage subjected to mechanical dehydration showed ruminal disappearance rates of dry matter and NDF, thus DISDM-48h and DISNDF-48h were superior for this method compared to the chemical method. There was a reduction in DISDM-48h and DISNDF-48h with advancing time of wilting in the field for haylage dehydrated by the chemical method. In general, the chemical dehydration method seems to be more related to better haylage making practices than nutritional factors, where the haylage obtained by mechanical dehydration is superior.

ABSTRACT: Although yeast supplementation has shown an immunostimulant effect in feedlot cattle, the question remains whether it influences the occurrence of the bovine respiratory disease complex (BRD) in feedlot cattle. Therefore, our objective was to evaluate whether dietary supplementation with autolyzed yeast affects the efficiency of blood phagocytes, reducing inflammation and the occurrence of BRD in feedlot cattle. A randomized experimental trial was conducted with whole steers with half Angus blood for 106 days: control (n=10): diet without yeast; Y4 (n=12): yeast diet (4g per animal per day); and Y7 (n=7): yeast diet (7g per animal per day). On Days 0, 14, 42, 70, and 105, blood count, leukocyte oxidative metabolism, serum haptoglobin, frequency of nasal secretion and orbital temperature were evaluated. On slaughter day, a lung evaluation was performed. On Days 42 and 70 of feedlot finishing, the treated animals showed increased leukocyte oxidative metabolism (D42 P=0.04; D70 P=0.02) compared to the control group. These animals had a lower frequency of mucopurulent nasal secretion, lower orbital temperature and reduced pneumonia occurrence than the treated groups (P=0.05) with less lung lesion severity (P=0.01), allowing us to infer that the autolyzed yeast improves blood phagocytic function and decreases the inflammation and BRD of feedlot steers, especially at a dose of 4g.

RESUMO: Embora a suplementação com leveduras tenha demonstrado efeito imunoestimulante em bovinos, permanece-se a dúvida se ela influencia na ocorrência do complexo doença respiratória bovina (CDRB) em bovinos confinados. Portanto, objetivou-se avaliar se a suplementação dietética com levedura autolisada influencia a eficiência de fagócitos sanguíneos, reduzindo inflamações e a ocorrência de CDRB em bovinos confinados. Realizou-se um ensaio experimental randomizado com 36 novilhos inteiros 1/2 sangue Angus por 106 dias: controle (n=10): dieta sem levedura; Y4 (n=12): dieta com levedura (4g por animal por dia); e Y7 (n=7): dieta com levedura (7g por animal por dia). Nos dias 0, 14, 42, 70 e 105, hemograma, metabolismo oxidativo de leucócitos, haptoglobina sérica, frequência de secreção nasal e temperatura orbital foram avaliados. No dia do abate, foi realizada avaliação pulmonar. Nos dias 42, e 70 de terminação em confinamento, os animais tratados apresentaram aumento do metabolismo oxidativo dos leucócitos (D42 P=0,04; D70 P=0,02) em relação ao grupo controle. Esses animais apresentaram menor frequência de secreção nasal mucopurulenta, menor temperatura orbital, menor ocorrência de pneumonias (P=0,05) com menor gravidade das lesões pulmonares (P=0,01), permitindo inferir que a levedura autolisada na dieta melhorou a eficiência dos fagócitos sanguíneos, reduzindo inflamações e a ocorrência de CDRB, especialmente na dosagem de 4g.

Resumo A flavomicina é um aditivo que pertence à classe dos não ionóforos, contudo, com poucos estudos realizados com bovinos confinados em fase de terminação. Diante disso, o objetivo do presente estudo foi avaliar a eficácia da flavomicina sobre o desempenho produtivo, comportamento ingestivo, características de carcaça e os parâmetros bioquímicos de novilhos terminados em confinamento. Foram avaliados 32 novilhos inteiros, ½ sangue Angus ½ sangue Nelore, provenientes do mesmo rebanho, com idade média de 11 meses ± 1,5 meses e peso corporal inicial de 337 kg ± 6 kg. O delineamento experimental foi o de blocos casualizados, composto por dois tratamentos e oito repetições, sendo: Dieta sem flavomicina (controle) e Dieta com flavomicina (0,5 g animal dia-1 do produto FLAVIMPEX®80). Não ocorrendo diferença entre os tratamentos, o consumo de matéria seca médio dos animais foi de 10,03 kg dia-1, eficiência alimentar de 0,158 kg, ganho médio diário de 1,593 kg dia-1, digestibilidade aparente da dieta de 61,69%. O uso da flavomicina não foi eficaz no desempenho animal, assim como não trouxe alterações no comportamento ingestivo e melhorias nas características de carcaça dos animais. A Proteína Plasmática Total, Aspartato amino-transferase e creatinina foram inferiores para os animais suplementados com flavomicina em relação ao grupo controle. Em relação ao período experimental houve redução nos índices de Proteína Plasmática Total, aumento na albumina, Gama-Glutamil Transferase e ureia dos bovinos, mas todos se mantiveram dentro dos valores de referência para a espécie.

Abstract Flavomycin is a non-ionophore additive little studied in finishing confined cattle. Therefore, this study aimed to evaluate the effectiveness of flavomycin on productive performance, ingestive behavior, carcass traits and biochemical parameters of steers finished in confinement. 32 whole steers, ½ Angus e ½ Nellore blood, from the same herd, with a mean age of 11 ± 1.5 months and initial body weight of 337 ± 6 kg were evaluated. The experiment was a randomized block design, consisting of two treatments and eight replications, as follows: Diet without flavomycin (control) and Diet with flavomycin (0.5 g FLAVIMPEX®80 animal day-1). There was no difference between treatments, the average dry matter intake of the animals was 10.03 kg day-1, feed efficiency was 0.158 kg, average daily gain was 1.593 kg day-1, apparent diet digestibility was 61.69%. The use of flavomycin was not effective in animal performance, and caused no changes in ingestive behavior and carcass traits of the animals. Total Plasma Protein, Aspartate amino-transferase and creatinine were lower for animals supplemented with flavomycin compared to the control group. In relation to the experimental period, there was a reduction in the levels of Total Plasma Protein, an increase in albumin, Gamma-Glutamyl Transferase and urea in cattle, but all remained within the reference range for the species.

ABSTRACT We investigated the effects of corn grain, finely or coarsely ground, rehydrated and ensiled to 35% moisture in substitution of dry corn grain on performance of beef cattle in the feedlot. Forty non-castrated young Angus crossbred bulls with average age of 13±1.4 months and average initial body weight (BW) of 374±14 kg. The experiment was conducted in blocks by weight, and bulls were randomly assigned into four groups of five animals each in a 2 × 2 factorial scheme. The factors evaluated were particle size (finely and coarsely ground) and two grain sources (dry ground corn and rehydrated corn grain silage). The treatments were diets containing dry corn grain, finely ground (DCF; 1.86 mm); dry corn grain, coarsely ground (DCC; 3.53 mm); rehydrated and ensiled corn grain, finely ground (RCF; 1.86 mm); and rehydrated and ensiled corn grain, coarsely ground (RCC; 3.53 mm). Initial BW, final BW, average daily gain (ADG), feed efficiency, and intake of dry matter (DMI), acid detergent fiber, and metabolizable energy were not affected by treatment. Ensiling corn grain decreased DMI by 10.3% (11.6 vs. 10.4 kg/d for dry and ensiled, respectively) and increased feed efficiency by 13.3% (0.13 vs. 0.15 kg/d for dry and ensiled, respectively), but there was no effect of particle size, grain source, and their interaction on ADG. Effects of particle size and grain source were observed for fecal starch and total tract starch digestion, with evidence that treatments containing rehydrated corn diets showed greater efficiency in the utilization of dietary starch. Animals fed RCF diets showed lower fecal starch losses of 37, 55, and 75% when compared with treatments RCC, DCF, and DCC, respectively. Our results suggested that ensiled rehydrated corn grain improves feed efficiency in substitution of dry corn grain. The finely and coarsely ground of rehydrated and ensiled corn grain increases the digestibility of starch for finishing cattle in feedlot.

ABSTRACT The objective of this study was to evaluate the effect of harvesting corn at different maturity stages for silage production combined with four storage periods, considering nutrient loss and the chemical composition of silage of the whole plant and also of grainless plants. The experiment was performed in a completely randomized design with a factorial arrangement of six maturity stages of corn [reproductive (R); R1 to R6] and four periods of silage storage (30, 60, 90, and 120 days). At stages R1 and R2, losses by effluents occurred more intensely when compared with the more advanced stages, whereas losses by gases showed the opposite behavior, with stage R6 responsible for the greatest losses. Stage R4 showed a stable dry matter (DM) content during the storage period, 42.08%, and had the lowest levels of neutral detergent fiber (NDF), acid detergent fiber (ADF), and acid detergent lignin (ADL) for the whole plant silage. The ADL in the silage of grainless plant of stage R4 was not the lowest, but it was close to the first reproductive stages, being an important point, since the first reproductive stages can present a vegetative fraction of better quality. The highest DM volumes produced by area occurred in the most advanced stages; however, R5 obtained a greater reduction in volume over the days of storage (20.66 kg day −1 ). The production cost was lower at the advanced stages (R4, R5, and R6) when compared with the first reproductive stages (R1, R2, and R3), and in general, during the storage period the costs did not have great variations. Based on the chemical composition of the silages, DM losses during the storage period, the stability in the costs of DM ton over the days of storage, the R4 stage was the most suitable for silage production.

Resumen Este estudio investigó la inclusión del ensilado de orujo de uva (EOU; 0, 10, 20 y 30 %), se evaluó en dietas de corderos, en la ingesta y digestibilidad de nutrientes, balance de nitrógeno y comportamiento ingestivo. Cuatro corderos de la raza Santa Inés con un peso de 21.93 ± 87 kg y aproximadamente siete meses de edad fueron alojados en jaulas metabólicas y distribuidos en un diseño cuadrado latino de 4x4. Los tratamientos consistieron en cuatro dietas con la inclusión de 0, 10, 20 y 30 % de EOU en las dietas. La ingesta de nutrientes se observó con un comportamiento lineal creciente para la ingesta de extracto etéreo (EE) (P<0.05) de acuerdo con el aumento de EE en las dietas, causado por el contenido de EE de las semillas en el EOU. Las dietas no difirieron en los coeficientes de digestibilidad de nutrientes y balance de nitrógeno (P>0.05), con una digestibilidad de materia seca (DMS) media de 678.6 ± 0.62 g kg-1 de MS y retención media de N de 239.78 g kg-1 de N ingerido. El comportamiento ingestivo de las dietas solo influyó (P<0.05) en el tiempo que los animales permanecieron inactivos de pie. Este parámetro mostró un comportamiento cuadrático con un punto máximo estimado en 17.73 % de EOU (P=0.041). En conclusión, se puede hacer uso de EOU hasta un nivel de inclusión del 30 % sin afectar negativamente a los parámetros evaluados.

Abstract This study investigated the inclusion of grape pomace silage (GPS; 0, 10, 20 and 30%) were evaluated in diets of lambs on nutrient intake and digestibility, nitrogen balance and ingestive behavior. Four lambs of the Santa Inês breed with weight of 21.93 ± 0.87 kg and approximately seven months old, were housed in metabolic cages and distributed in a 4x4 latin square design. The treatments consisted of four diets with the inclusion of 0, 10, 20 and 30% GPS in diets. The nutrient intake was observed an increasing linear behavior for ether extract (EE) intake (P<0.05) according to the increase of EE in the diets, caused by content of EE of seeds in GPS. The diets did not differ in the digestibility coefficients of nutrients and nitrogen balance (P>0.05), with average digestibility of dry matter digestibility (DDM) of 678.6 ± 0.62 g kg-1 DM and average retention of 239.78 g kg-1 N ingested of N. The ingestive behavior the diets were influenced (P<0.05) by only the length of time that the animals remained idle in standing. This parameter showed a quadratic behavior with a maximum point estimated at 17.73 % of GPS (P=0.041). In conclusion, the use of GPS can be used until inclusion level of 30 % without negatively affecting the parameters evaluated.

Abstract Triticale high moisture grain triticale silage is an excellent option for ruminant diets, but loss control during its fermentation process should be further investigated. Thus, the objective of this study was to evaluate the effects of chemical and biological additives on high moisture triticale silages under chemical-bromatological composition, aerobic stability, and in vivo digestibility and ingestive behavior in sheep. The treatments were: high moisture triticale silage without additive (HMTC); high moisture triticale silage with enzyme-bacterial inoculant (HMTEB); high moisture triticale silage with 0.5 % urea in natural matter (HMTU); and high moisture triticale silage with 1.5 % sodium benzoate in natural matter (HMTSB). Four sheep were housed in appropriate metabolic cages according to the ethical principles of animal experimentation. The addition of urea as additive to high moisture triticale silage provided an increase in crude protein and ammoniacal silage (189.7 and 106.2 g kg MS-1, respectively) but did not affect digestibility (699.6 g kg MS-1 for HMTU, with a general average of treatments of 687.5 g kg MS-1) and ingestive behavior of sheep. Fiber consumption by sheep increased with the addition of the enzyme-bacterial additive in the silage (431.87 versus 388.06 g d-1 of FDN for HMTEB and HMTC, respectively). All additives helped to preserve crude protein contents after silo opening, but none interfered in aerobic stability time of silage.

Resumen El ensilaje de triticale de grano con alto contenido de humedad es una excelente opción para las dietas de rumiantes. Sin embargo, falta información sobre el control de pérdidas durante el proceso de fermentación. Se hizo una evaluación sobre los efectos de los aditivos químicos y biológicos a ensilajes de triticale de alta humedad en la composición química-bromatológica, la estabilidad aeróbica, la digestibilidad in vivo y el comportamiento de ingesta en ovinos. Se evaluaron cuatro tratamientos: ensilaje de triticale sin aditivo (control); ensilaje con un inoculante enzimático-bacteriano; ensilaje con 0.5% de urea en materia natural; y ensilaje con benzoato de sodio al 1.5% en materia natural. El comportamiento de ingesta se evaluó con cuatro ovejas macho en jaulas metabólicas. La adición de urea como aditivo proporcionó un aumento en el contenido de la proteína cruda (189.7 g kg MS-1) y el nitrógeno amoniacal (106.2 g kg MS-1), pero no afectó la digestibilidad (699.6 g kg MS-1 en tratamiento con urea, promedio = 687.5 g kg MS-1) ni el comportamiento de ingesta. El consumo de fibra aumentó con la adición del aditivo enzimático-bacteriano (431.87 vs 388.06 g d-1 fibra detergente neutra en el control). Todos los aditivos ayudaron a preservar el contenido de proteína cruda después de la apertura del silo, pero ninguno interfirió en el tiempo de estabilidad aeróbica del ensilado.

ABSTRACT. Maize forage is commonly used as silage in milk and beef cattle livestock production systems. Despite the wide variety of maize hybrids with high potential for grain production, few available hybrids have been developed exclusively for forage aptitude. The present study aimed to select S3 maize progenies derived from the single hybrid AS1572 based on the combining ability of forage traits in topcrosses with testers AG8025, 70.H26.1, and MLP102. The 135 resulting topcross hybrids were assessed in partial diallel in Guarapuava and Rio Bonito do Iguaçu, Paraná State, Brazil. Were evaluated the contents of neutral detergent fiber (NDF, %DM) and acid detergent fiber (ADF, %DM), forage dry matter yield (DMY, t ha-1), and in situ digestibility of forage dry matter (DIG, %DM). For all evaluated traits, the variability allowed us to select superior progenies. Progenies 3.1, 22.1, and 39.1stood out in terms of NDF, ADF, and DIG, whereas progenies 47.1, 73.1, 79.1, and 90.2 were efficient in increasing the forage dry matter yield. The testers AG8025 and 70.H26.1, of narrow genetic base, are the best to explore genetic variability among progenies.

Resumo O objetivo deste trabalho foi avaliar a eficiência de diferentes filmes plásticos dupla face sobre as características quimiofermentativas, digestibilidade da matéria seca, estabilidade aeróbica, perdas físicas e de matéria seca de silagens de milho armazenadas em silos trincheira. O delineamento experimental utilizado foi inteiramente casualizado, compostos por três tratamentos: DF110µm - polietileno dupla face com espessura de 110 µm; DF200µm - polietileno dupla face com espessura de 200 µm; e DFBO - película impermeável ao oxigênio composta de polietileno dupla face com espessura de 80 µm sobreposta a uma película de poliamida translúcida a vácuo com espessura de 20 µm. O uso do filme DF200µm aumentou em 4,58% a digestibilidade ruminal da matéria seca e reduziu em 3,1 °C a temperatura da silagem, assim como as perdas físicas da silagem de milho foram reduzidas em 118,9 g kg-1 da MS pela utilização do DFBO e 95 g kg-1 da MS com o DF200µm, o DFBO apresentou a maior estabilidade aeróbica (127 horas) da silagem de milho. O uso de filme DF200µm e DFBO é recomendado para conservação de silagem de milho em silos do tipo trincheira.

Abstract The objective of this study was to evaluate the efficiency of different double-sided plastic films on chemical and fermentation characteristics, dry matter digestibility, aerobic stability, physical and dry matter losses in corn silages stored in bunker silos. This was a completely randomized experimental design consisting of three treatments: DF110µm - double-sided polyethylene with 110 µm thickness; DF200µm - double-sided polyethylene with 200 µm thickness; and DFBO - oxygen-impermeable film consisted of double-sided polyethylene with 80 µm thickness overlaid with a translucent vacuum polyamide film with 20 µm thickness. The use of DF200µm film increased the ruminal dry matter digestibility by 4.58% and reduced the silage temperature by 3.1 °C, as well as the physical losses of the corn silage were reduced by 118.9 g kg-1 DM using DFBO and 95 g kg-1 DM with DF200µm; DFBO resulted in the highest aerobic stability (127 hours) of corn silage. The use of DF200µm and DFBO is recommended for preserving corn silage in bunker silos.

Resumo O objetivo deste trabalho foi avaliar a qualidade químico-fermentativa da silagem de dois híbridos de sorgo nos diferentes estratos da face do silo e a interferência do tempo de exposição aeróbia da face do silo estruturada e/ou desestruturada (após desensilagem). A silagem do híbrido AG-2005E apresentou maior teor de proteína bruta e pH mais elevado em comparação à do híbrido AG-60298 (6,33% e 4,0 contra 6,06% e 3,8, respectivamente). As silagens do estrato de 0 a 20 cm tinham o menor teor de matéria seca e o maior teor de proteína bruta (38% e 6,35%, respectivamente). O pH não diferiu entre os estratos e o teor de NH3 foi maior no estrato de 60 a 80 cm (4,5%). Com o avanço das 72 horas de exposição aeróbia, a silagem desestruturada apresentou maior incremento de temperatura em relação à silagem da face estruturada, mas esse tempo não foi suficiente para mostrar diferenças entre os teores de matéria seca, matéria mineral, NH3 e pH. O híbrido de sorgo e o estrato do silo interferem diretamente na qualidade químico-fermentativa da silagem. Após a exposição aeróbia, a silagem do painel do silo estruturado parece sofrer menor interferência em relação à silagem após ser desensilada.

Abstract This study aimed to evaluate the chemical and fermentation quality of silage from two sorghum hybrids in different layers of the silo feed-out face, as well as the interference of the aerobic exposure time of structured and/or unstructured silo face (after feed-out). The AG-2005E hybrid silage presented higher crude protein content and higher pH compared to hybrid AG-60298 (6.33% and 4.0 versus 6.06% and 3.8, respectively). Silages from stratum 0 to 20cm had the lowest dry matter content and the highest crude protein content (38% and 6.35%, respectively). The pH did not differ between layers, and the NH3 content was higher in the stratum 60 to 80cm (4.5%). During 72 hours of aerobic exposure, the unstructured silage presented a higher increase in temperature than the silage from the structured face, but this period was not enough to result in differences in dry matter, mineral matter, NH3, and pH. The chemical and fermentation quality of the silage was directly influenced by hybrid and silo stratum. After aerobic exposure, silage from the structured face seems to suffer less interference compared to the silo feed-out face.

Resumo Objetivou-se neste trabalho avaliar alimentos energéticos quanto a composição química, degradabilidade ruminal in situ da matéria seca (DMS), cinética ruminal e taxa de desaparecimento ruminal da matéria seca. Foram avaliados sete alimentos (tratamentos): grão de milho moído, grão de aveia moído, grão de cevada moído, farelo de trigo, casca de soja, radícula de malte e gérmen de milho, num delineamento inteiramente casualizado com quatro repetições cada. Para a incubação dos materiais foram utilizados dois bovinos com cânula ruminal, e cada tratamento foi submetido a sete períodos de exposição ao rúmen (0, 3, 6, 9, 12, 18 e 24 horas). Dentre os alimentos avaliados, a casca de soja teve o maior teor de fibra em detergente neutro (68,91%) e apresentou a menor DMS em 24 h (64,91%). O grão de cevada moído e o grão de milho moído tiveram os menores níveis de fração solúvel (FS) (26,34% e 28,7%, respectivamente), porém o grão de cevada moído apresentou a maior DMS em 24 h (90,48%), que por conciliar estes parâmetros teve a maior taxa de desaparecimento ruminal (2,50%.h-1), enquanto o grão de aveia moído teve a maior FS (47,75%) e a menor taxa de desaparecimento ruminal (1,09%.h-1).

Abstract This study aimed to evaluate energetic feedstuffs regarding chemical composition, in situ ruminal degradability of dry matter (DMD), ruminal kinetics and ruminal disappearance rate of dry matter. Seven feedstuffs (treatments) were evaluated: ground corn, ground oat, ground barley, wheat bran, soybean hull, malt root and corn germ, in a completely randomized design of four repetitions each. Two bovines ruminally cannulated were used for incubation, wherein each treatment was subjected to seven periods of exposure to the rumen (0, 3, 6, 9, 12, 18 and 24 hours). Among the evaluated feedstuffs, soybean hull had the highest neutral detergent fiber (NDF) content (68.91%) and the lowest DMD at 24 h (64.91%). Ground barley and ground corn contained the lowest content of soluble fraction (SF) (26.34 and 28.7%, respectively), among which ground barley had the highest DMD at 24 h (90.48%) and therefore showed the highest rumen disappearance rate (2.50%.h-1) by combining both parameters, while the ground oat presented the highest SF (47.75%) and the lowest rumen disappearance rate (1.09%.h-1).

Resumo O experimento foi conduzido com o objetivo de avaliar o efeito de elevar a altura de corte da planta de milho destinada a confecção de silagem, perante a produção de biomassa seca e possíveis influencias no desempenho de cordeiros confinados. Os tratamentos utilizados foram. SM20 Silagem de milho colhida a 20 cm de altura; SM80 Silagem de milho colhida a 80 cm de altura. A realização do corte a 80 cm do solo reduziu a produção de biomassa seca em 2.375 kg MS ha-1, porém não reduziu a capacidade de suporte e melhorou a digestibilidade do alimento fornecido em 4,59%, além de melhorar a conversão de carcaça, eficiência de transformação em carcaça e o rendimento de carcaça em 1,04%, 4,68% e 2,20%, respectivamente, em relação aos animais alimentados com a silagem cortada a 20 cm do solo. A produção de silagem colhida mais distante do solo proporciona menores volumes por área, porém aumenta a qualidade do alimento final e melhora o desempenho dos animais.

Abstract This experiment was conducted to evaluate the effect of raising the cutting height of the corn plant destined to silage production, in relation to the dry biomass production and possible influence on the performance of confined lambs. The treatments tested were: SM20: Corn silage harvested at 20 cm height. SM80: Corn silage harvested at 80 cm height. Cutting at 80 cm from the ground reduced the dry biomass production by 2.375 kg DM ha-1, but did not reduce the carrying capacity and improved the digestibility of the feed by 4.59%, besides improving the carcass conversion, carcass transformation efficiency and carcass yield by 1.04%, 4.68% and 2.20%, respectively for animals fed silage of corn cut at 20 cm from the ground. Production of silage harvested farther from the ground provides smaller volumes per area, but increases the quality of the final feed and improves the performance of the animals.

ABSTRACT. The objective of this work was to evaluate the chemical composition and rumen disappearance rate of dry matter of corn silages with inoculants combining L. buchneri strain LN40177 in different strata of the silo. The experimental design was a 3x2 randomized complete block design, with three treatments: Control: corn silage without inoculant; 11CFT: corn silage with inoculant which combines L. buchneri strain LN40177 (1.1 x 1011 CFU g-1) with L. casei (1.1 x 1011 CFU g-1); and 11C33: corn silage with inoculant which combines L. buchneri strain LN40177 (1.1 x 1011 CFU g-1) with L. plantarum (1.1 x 1011 CFU g-1) and Enterococcus faecium (1 x 1010 CFU g-1), associated with two strata of the silo (lower and upper). The silage inoculated with 11C33 presented higher contents of crude protein and NDF and lower hemicellulose content in relation to the control treatment and 11CFT. The use of both inoculants resulted in silages with higher concentrations of soluble nutrients. Lower stratum silage had a higher rumen disappearance rate of dry matter compared to the upper stratum. In general, the combinations of L. buchneri promoted nutritional improvements in corn silage, but in presence of L. casei, there were more outstanding improvements.

Objetivou-se avaliar a ingestão de matéria seca, ganho de peso diário, conversão alimentar, digestibilidade e as características da carcaça de novilhos alimentados com dietas à base de silagens de dois híbridos de milho. Os tratamentos foram as silagens de milho provenientes dos híbridos LG6030 PRO e P30B39H. O delineamento experimental foi o inteiramente casualizado, com seis repetições, em esquema de parcelas subdivididas no tempo, em três períodos de avaliação. Animais alimentados com a silagem de milho LG6030 PRO tiveram maior (P<0,05) ganho médio de peso e melhor conversão alimentar. O tipo de silagem não alterou (P>0,05) a ingestão de matéria seca, ganho médio de carcaça e ganho de carcaça no período de terminação. Contudo, com o hibrido LG 6030 PRO houve melhor eficiência de transformação da matéria seca consumida em carcaça, apesar de menor eficiência de transformação do ganho de peso em carcaça (73,7 contra 76,9%) comparativamente com a dieta com silagem de P30B39H. Além disso, a digestibilidade aparente foi maior (P<0,05) para silagem de milho do híbrido LG6030 PRO, obtendo eficiência de digestão 3,4% superior. Os componentes de rendimento não integrantes da carcaça não foram alterados em função das variações dietéticas das silagens avaliadas. Sendo assim, recomenda-se o híbrido LG6030 PRO para produção de silagem.

This work aimed to evaluate the dry matter consumption, daily weight gain, feed conversion, digestibility and carcass characteristics of confined steers fed with silages from different corn hybrids. The treatments were the silages from the hybrids LG6030 PRO and P30B39H. The experimental design was totally randomized, with 6 repetitions, in a split-plot scheme, in three evaluation periods. Animals fed with silage from hybrid LG6030 PRO showed a higher daily weight gain and better food conversion. The silage type did not alter (P>0.05) dry matter consumption, average carcass gain and carcass gain during the finishing period. However, the hybrid LG6030 PRO improved the efficiency transformation of consumed dry matter into carcass, despite the decrease of efficiency of transformation of weight gain into carcass (73,7 vs 76.9%) comparatively to animals fed with P30B39H silage. Diets containing the hybrid LG6030 PRO reflected in an increase of 3.4% of apparent digestibility. There were no differences of non-carcass components yield between the treatments in this experiment. It is recommended LG6030 PRO for silage production.

RESUMO. Esse estudo objetivou avaliar a composição bromatológica da forragem e da silagem pré-secada de doze cereais de inverno colhidos em estádio de pré-florescimento. Utilizou-se aveia preta (Avena strigosa) cv. EMB 139 e cv. IAPAR 61, aveia branca (Avena sativa) cv. IPR 126 e cv. URS Taura, cevada (Hordeum vulgare) cv. BRS Brau e cv. BRS Cauê, trigo (Triticum aestivum) cv. BRS Umbu e cv. BRS Tarumã, centeio (Secale cereale) cv. Temprano e cv. BRS Serrano e triticale (X Triticosecale) cv. IPR 111 e cv. BRS Saturno. A colheita ocorreu quando as plantas atingiram estádio de pré-florescimento, onde foram pré-murchadas e ensiladas. O triticale cv. IPR 111 apresentou características químicas notórias em relação aos demais tratamentos, tendo o maior teor de proteína bruta (113,7 g kg-1) e os menores teores de FDN e FDA (657,9 e 380,9 g kg-1, respectivamente). Dentre as silagens pré-secadas a cevada cv. BRS Cauê apresentou a maior concentração de NDT (614,7 g kg-1). O triticale cv. IPR 111 se mostrou como um alimento de alta qualidade nutricional enquanto forragem, e manteve essas características após conservação. Já a silagem pré-secada da cevada cv. BRS Cauê apresentou o maior potencial de degradabilidade de nutrientes.

ABSTRACT. This study aimed to assess the chemical composition of the forage and pre-dried silage from twelve winter cereals harvested at pre-flowering. We used black oat (Avena strigosa) cv. EMB 139 and cv. IAPAR 61; white oat (Avena sativa) cv. IPR and 126 hp. URS Taura; barley (Hordeum vulgare) cv. BRS Brau and cv. BRS Cauê; wheat (Triticum aestivum) cv. BRS Umbu and cv. BRS Tarumã; rye (Secale cereale) cv. Temprano and cv. BRS Serrano; and triticale (X. Triticosecale) cv. IPR and 111 hp. BRS Saturno. Plants were harvested at pre-flowering, when they were pre-dried and ensiled. The analysis of variance evidenced nutritional differences between species and cultivars. Triticale cv. IPR 111 showed notorious chemical characteristics in relation to the other treatments, highest protein content (113.7 g kg-1) and lower content of NDF and ADF (657.9 and 380.9 g kg-1, respectively). Among the pre-dried silages, barley cv. BRS Cauê had the highest level of NDT (614.7 g kg-1). Triticale cv. IPR 111 was shown as a high-quality nutritional food as forage and kept these characteristics after conservation. On the other hand, the pre-dried silage of barley cv. BRS Cauê showed the highest potential for nutrient degradability.