he objective of this study was to evaluate the production and physical composition of three maize hybrids (Zea mays, L.) for silage production at six maturity stages. The hybrids evaluated were Maximus VIP3, Defender VIP and Feroz VIP. The experiment was conducted in a completely randomized block design with four replicates. The mean plant heights observed at harvest time (2.33 m, 2.45 m and 2.40 m) demonstrated that all materials were medium-sized hybrids. A positive correlation was observed between plant height and height of the ear insertion, varying from 0.86 for the Feroz VIP hybrid to 0.88 for the Maximus VIP3 hybrid, but these two variants had no correlation with the productivity data. There was a significant difference for the production of fresh biomass at the R1, R2 and R5 stages, with Maximus VIP3 obtaining the highest yields. The proportion of grains in the physical composition of plant varied between hybrids, where Maximus VIP3 and Defender VIP (482.2 and 461.7 g kg-1, respectively) were superior to Feroz VIP (429.7 g kg-1). With the advancement of maturity, there was a decreasing linear behavior for stem and leaf participation, with reductions of 3.8 g kg-1 and 4.5 g kg-1, respectively, per day (R2 = 0.79 and 0.80, respectively), quadratic behavior for bracts and corncob and a linear increase in grain participation in the plant structure, with an increase of 7.7 g kg-1 per day (R2 = 0.88). In general, the three hybrids present good characteristics for silage production and permit harvesting in the hard grain stage, allowing the addition of starch in relation to the farinaceous grain stage.

This study aimed to evaluate the production, the physical and nutritional composition of forage and silage, as well as the profitability and aerobic stability of different winter cereals harvested at the stage of floury grain. The experimental design was a 2x7 factorial randomized block design, with two forms of foods (fresh forage and silage) and seven genotypes, with four replications. The genotypes used were the white oat (Avena sativa) cv. URS Taura; barley (Hordeum vulgare) cv. BRS Brau and cv. BRS Cauê; wheat (Tricticum aestivum) cv. CD 1440; rye (Secale cereal) cv. BR 01; and triticale (X Triticosecale) cv. IPR 111 and cv. BRS Saturno. The materials were harvested during the stage of floury grain. In forage evaluation, rye showed the highest (P < 0,05) dry biomass production (7,100 kg ha-1), but with a higher percentage of stem (46.7%) in dry matter, implying higher ADF (44.69%) in relation to other cereals. The forage of the white oats cv. URS Taura and triticale cv. IPR 111 provided the best nutritional quality compared to the other evaluated cereals, but in the resulting silage, only triticale remained with forage-like characteristics. It was clear the superiority of barley cv. BRS Cauê, wheat cv. CD 1440 and rye cv. BR 01 regarding the maintenance of aerobic stability (160 hours), while the other silages lost their stability within 32 hours. Rye cv. BR 01 and triticale IPR 111 presented the highest production of recovered dry biomass (5,402 and 5,352 kg ha-1 respectively), barley cv. BRS Cauê and oat URS Taura provided higher cost of production per kg-1 dry biomass, both with R$ 0.29 and higher cost per kg of recovered dry biomass R$ 0.45 and 0.37 respectively. There are several factors to consider when choosing the winter species for silage production, and future studies can fully elucidate these factors.

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.

RESUMO.Os consumidores estão cada vez mais exigentes em relação a qualidade da carne consumida em virtude do aumento da renda per capita. Todavia, o padrão cárneo brasileiro possui diversos entraves sob tal ótica. Desta forma, esta revisão de literatura visa abordar as principais diferenças da carcaça e da carne de bovinos sob diferentes sistemas de terminação. Palavras chave: Confinamento, idade ao abate, marmoreioAspects that influence the tenderness cattle meat: Review ABSTRACT. Consumers are becoming increasingly demanding for meat quality due to the increased of the per capita income. However, the Brazilian meat pattern has a lot of problems on these circumstances. So, this review approaches the main differences of carcass and cattle meat in different finishing systems.

ABSTRACT. Enzymes can be an interesting additive in high energy diets for feedlot cattle. However, literature is inconsistent on this subject. Thus, this study was conducted to evaluate animal performance of feedlot bulls receiving high energy diet, composed of a mixture of 85% whole corn grain and 15% proteinmineral-vitamin nucleus, without or with xylanase included in the diets. Diets consisted of: CON -diet without enzymes (Control) and ENZ -diet with enzymes (5 g animal day -1). Thirty-two bulls were used, with an average age of 11 ± 2 months, average initial weight of 365 ± 5 kg, and finished for 119 days in feedlot. The experimental design was completely randomized, consisting of two treatments and eight replications, where each replication was represented by a stall with two animals. ENZ increased the weight gain (1.69 vs. 1.33 kg day -1) and improved the feed conversion (4.60 vs. 6.03 kg -1 ) in the adaptation period of the animals. Animals receiving ENZ increased 1.65% of carcass yield and were 7.57% more efficient in the conversion of dry matter consumed into carcass gain in relation to CON. Carcass traits of feedlot-finished bulls were not altered by inclusion of enzymes. Xylanase-complex could increase efficiency in feedlot bulls.Keywords: beef cattle, feed additive, ruminant nutrition.Eficiência do complexo xilanase em dietas de alta energia para touros terminados em confinamento RESUMO. As enzimas podem ser aditivos interessantes em dietas de alta energia para gado em confinamento. No entanto, a literatura é inconsistente para este assunto. Assim, este trabalho foi realizado para avaliar o desempenho de touros em confinamento com dietas de alta densidade energética, composto apenas de uma mistura de 85% de grãos de milho inteiros e 15% de núcleo proteico-vitamínico-mineral, com ou sem inclusão de enzimas à base de xilanase. Os tratamentos foram CON -dieta sem enzimas (controle) e ENZ -dieta com enzimas (5 g animal dia -1 ). Foram utilizados 32 touros, com idade média de 11 ± 2, peso inicial médio de 365 kg ± 5 e terminados por 119 dias. O delineamento experimental foi inteiramente casualizado, consistindo em dois tratamentos e oito repetições, em que cada repetição foi representada por uma baia com dois animais. ENZ aumentou o ganho de peso (1,69 vs. 1,33 kg dia -1 ) e melhorou a conversão alimentar (4,60 vs. 6,03 kg -1 ) na fase de adaptação dos animais em confinamento. Os animais que receberam ENZ aumentaram 1,65% do rendimento de carcaça e foram 7,57% mais eficientes na transformação da matéria seca consumida no ganho de carcaça em relação ao CON. As características de carcaça de touros terminados em confinamento não foram alteradas em função da inclusão de enzimas. O complexo de xilanase pode aumentar eficiência de touros de confinamento.Palavras-chave: bovinos de corte, aditivo alimentar, nutrição de ruminantes.