The objective of this study was to evaluate the postweaning history of heifers kept on marandu grass pastures with three canopy heights, in a continuous-grazing system, during the rainy period, on feedlot- or pasture finishing. The effects of three canopy heights (15, 25 and 35 cm) associated with two supplements (mineral salt and protein-energy supplement) and two finishing systems in the dry period (feedlot and open pasture) were studied in the postweaning period during the rainy season. The adopted design was completely randomized, with seven replications (animals) in a 2 × 2 factorial arrangement. The animals which received protein-energy supplement reached the finishing period with greater body weight in relation to those fed mineral salt. In both feedlot and pasture finishing systems, compensatory gain effect was observed in the animals that remained on the low pastures during postweaning compared with the high pastures. This compensatory gain was not verified in the animals that received protein-energy supplement in relation to the mineral salt, and thus the animals were slaughtered beforehand. The heifers on pastures with 25 or 35 cm in height were slaughtered in the same period, and those kept on the low pastures were slaughtered afterwards. The studied factors in the postweaning phase did not affect the carcass characteristics. Animals finished in feedlot slaughtered with the same body weight as those finished on pasture show greater carcass yield, subcutaneous fat deposition and renal pelvic and inguinal fat and greater losses with trimmings for cleaning the main hindquarter meat cuts; however, they provide cuts with the same weight but greater fat cover.

The experiment was carried out on Cynodon spp cv. Tifton 85 pastures grazed by sheep under rotational stocking, with the objective of evaluating the structural characteristics as well as the forage mass of the pastures subjected to three grazing intensities in successive cycles. Treatments were composed of three residual leaf area indices (rLAI; 2.4; 1.6 and 0.8), allocated in completely randomized blocks with seven replications, totaling 21 experimental units. Tiller population density, pasture height, leaf area index, forage morphological composition and pasture forage mass were evaluated. The rLAI modified the tiller population density, which increased linearly with decrease in the rLAI of the pastures. Dry masses of leaf blade, stem and dead material were inferior when the rLAI imposed were lower, which resulted in differentiated forage production among the treatments. Tifton 85 pastures grazed by sheep in rotational stocking under tropical conditions with different rLAI show a modified sward structure over successive grazing cycles, mainly by alteration in the height and LAI of the plants at pre-grazing and by light interception post-grazing, which change the tiller population density. The residual leaf area index of 1.6 is the most suitable for pasture management for being equivalent to the heights of entrance and exit of animals on and from paddocks of 33 and 19 cm, respectively, which avoid great accumulation of dead material and excessive stem elongation, in addition to ensuring tillering in the sward.

Fermentation and aerobic stability were evaluated in high-moisture corn (HMC) silage inoculated with different levels of Lactobacillus buchneri. The HMC composed of 654 g/kg dry matter (DM) was ensiled in quadruplicate laboratory silos (7 L) per treatment. L. buchneri 40788 was applied at 5 × 10(4); 1 × 10(5); 5 × 10(5); and 1 × 10(6) cfu/g to the ground corn. Silages with no additive were used as controls. After 140 d of ensiling, the silages were subjected to an aerobic stability evaluation for 12 days in which the chemical parameters, microbiological parameters and silage temperature were measured to determine the aerobic deterioration. The lactic acid, acetic acid and propionic acid concentrations did not differ between silages. The fermentation parameters of HMC were not affected by L. buchneri. The HMC containing L. buchneri had a low number of yeast and mould colonies and a more stable pH until in the eighth measurement, which improved the aerobic stability without affecting gas loss. Doses of L. buchneri greater than or equal to 5 × 10(5) cfu/g applied to the HMC were the most efficient in control of aerobic deterioration.

The objective of the present study was to evaluate the characteristics of the sward canopy of Marandu grass during the rainy season, the wet-to-dry transition and the dry seasons, between March and September 2004, under intermittent grazing, and to correlate those characteristics with the performance of crossbred heifers receiving mineral supplements ad libitum or protein supplements. The experiment consisted of a randomized block design with three blocks (set of 13 paddocks), each containing five crossbred heifers per experimental unit, totaling 15 replicates. The heifers were given protein supplements daily in individual stalls and received an average 4 g/kg/day of the supplement during the rainy season and 5 g/kg/day during the dry season. Their weight gain was assessed monthly. The pasture structure was assessed through destructive sampling, and the bromatological composition of esophageal extrusa samples was also assessed. Analysis of variance was used to assess performance, and regression analysis was used to evaluate the sward canopy characteristics in relation to the months of the year. A cluster procedure was used to determine the similarity between the months of the year under assessment. Two different groups were formed for pasture evaluation: one group including the months of March to July and another group including the months of August and September. The first group exhibited a better canopy structure than the second group. This fact was corroborated by the animal performance, which was lower during the months of the second group. Low-intake protein supplementation was effective in increasing the performance of the grazing heifers. Pasture structure is critical for animal performance in a grazing environment, regardless of the type of supplementation.

An experiment was conducted during the 2001-2002 winter-spring-summer to determine the nitrogen and carbohydrate fractions in Tifton-85 pastures exclusively or overseeded with oats, millet and sorghum-sudangrass hybrids. The treatments were Tifton-85 overseeded with millet + bristle oat; sorghum-sudangrass + bristle oat, on 06/19/2002 and 07/02/2002, respectively; and Tifton-85 (Control). The experiment was conducted in a randomized block design with three replications. Nitrogen and carbohydrate fractions were affected by the nitrogen and total carbohydrate contents observed in the pasture overseeded at different seeding times, and by the different growth periods. The highest nitrogen fractions (A + B1) were observed in the early growth periods. Overseeding affected the forage nitrogen and carbohydrate fraction contents positively. The high solubility of both carbohydrate and protein from millet + bristle oat and bristle oat + sorghum-sudangrass mixtures indicates the quality of these forages and their potential use as an important supplement in forage systems based on tropical pastures.

The objective of this study was to evaluate the Brachiaria brizantha cv. Marandu canopy structure maintained at different grazing heights under a continuous stocking rate and with a dietary supplementation strategy for the animals during the rainy season. This study also intended to observe the relationships of these variables with the grazing behaviors of the heifers. The effects of three canopy heights (15, 25 and 35 cm) were evaluated in association with three types of supplements: one mineral and two protein/energy supplements, the first with a high rumen degradable protein and energy and the others with a low ratio. Both the protein/energy supplements were provided at 0.3% of body weight/day. The experimental design was completely randomized, with two replications and repeated measures, and took place during the period from January to April 2008. The supplementation strategies did not affect any variable related to the canopy structure. Total and green herbage masses and the ratio of green/dead material increased with canopy height. The leaf/stem ratio was higher in the lowest canopy height: 15 cm. Changes in the canopy structure caused variations in the grazing behavior of the animals. Animals maintained in the 15-cm-tall pasture grazed for a longer time, increasing the time for each meal, but the number of meals was lower than that of the animals grazing within the 35-cm-tall pasture. The grazing time of animals receiving the energy/protein supplement was lower only in the period of the day during which it was supplied. Canopy structure is affected by sward height, and changes animal behavior. Supplementation does not affect the canopy structure of the pastures with similar heights.

The objective of this study was to assess the sward canopy structure of Brachiaria brizantha cv. Marandu pastures maintained in three grazing intensities under continuous stocking system during the rainy season, along with the behavior and performance of grazing beef heifers supplemented with mineral salt or an energy/protein supplement. Three levels of forage allowance were assessed: 2.0, 2.5 and 3.0 kg of forage/kg of live weight, combined with two supplements (ad libitum mineral salt, and an energy/protein supplement at 0.3% of live weight/day, supplied daily). The experiment was designed as a randomized block study with two replications. The supplements did not influence the variables related to the canopy structure. Canopy height was greater at higher forage allowances during the late summer and early fall. Similarly, the stem mass was greater in pastures with higher forage allowances. Animals fed protein supplement spent less time grazing than animals supplemented with mineral salt. Stocking rate was higher in pastures with lower forage allowance levels, which increased the live weight gain per grazing area. Daily weight gain did not vary according to the forage allowance levels. The use of an energy/protein supplement did not affect the stocking rate; however, it increased individual live weight gain and live weight gain per grazing area compared with mineral salt supplementation. The use of energy/protein supplements is an efficient alternative to enhance animal performance and production under grazing systems during the rainy season

Avaliaram-se as características morfogênicas e estruturais do dossel de Brachiaria brizantha, cv. Marandu, sob pastejo intermitente no período chuvoso, em diferentes ofertas de forragem e ciclos de pastejo. O delineamento experimental foi em blocos ao acaso, em esquema de parcelas subdivididas, com três repetições. Nas parcelas, avaliou-se o efeito das ofertas de forragem (4, 7, 10 e 13% do PV/dia) e, nas subparcelas, o efeito dos ciclos de pastejo. Todas as variáveis diferiram entre os ciclos de pastejo, comprovando grande influência das condições ambientais sobre as características avaliadas. A taxa de alongamento do colmo e a altura do dossel responderam linear e positivamente ao aumento da oferta de forragem. O número de perfilhos vegetativos nos piquetes com a menor oferta permaneceu constante ao longo de todo o período experimental, no entanto, nos piquetes com as demais ofertas, atingiu valores mais elevados nos ciclos intermediários. A densidade de perfilhos reprodutivos e totais ajustou-se ao modelo quadrático de acordo com a oferta de forragem. Pastos manejados com ofertas de forragem próximas a 4% PV/dia têm menor alongamento de colmos e tendem a reduzir as perdas por senescência. As variáveis ambientais exercem maior influência sobre as características morfogênicas e estruturais em comparação a ações de manejo como a oferta de forragem.

It was evaluated morphogenetic and structural characteristics of the canopy of Brachiaria brizantha cv. Marandu under continuous grazing during the wet season, in different forage supplies and grazing cycles. A random block experimental design was used in a split-plot scheme with three replicates. It was evaluated in the plots the plots, the effects of forage supplies (4,7, 10 and 13% BW/day) and in the subplots, the effects of grazing cycles were evaluated. All the variables differed among grazing cycles, proving the great influence of environmental conditions on the evaluated characteristics. Stem elongation rate and canopy height showed linear and positive responses to the increase on forage supply. Number of vegetative tillers in the plots with the lowest supply was constant over the whole experimental period, however, in the plots with the other supplies, tillers reached highest values in the intermediate cycles. Density of total and reproductive tillers was fitted to the quadratic model accordingly to the forage supply. Pastures managed with forage supplies close to 4% BW/day showed lower stem elongation and they tend to reduce loses caused by senescence. Environmental variables affect morphogenetic and structural characteristics more than management with forage supply does.

Objetivou-se avaliar os efeitos de nitrogênio (0, 100, 200, 300 e 400 kg/ha.ano), com ou sem aplicação de calcário dolomítico em cobertura, sobre o teor de potássio (K) do solo nas profundidades de 0 a 5; 5 a 10; e 10 a 20 cm e a concentração de potássio na planta. O experimento foi realizado em Latossolo Vermelho distroférrico de relevo suavemente ondulado, disposto em esquema fatorial 5 × 2, em blocos casualizados, com quatro repetições. A adubação nitrogenada promoveu aumento linear na concentração de potássio na planta e no teor desse mineral na camada de 0 a 5 cm do solo. Ocorreu efeito de inibição competitiva entre a absorção de potássio e cálcio e entre potássio e magnésio. Embora uma fração significativa de potássio retorne à camada superficial do solo pelo resíduo de forragem, em decorrência da maior produção de massa, o aumento da concentração de potássio na planta nas mais altas doses de nitrogênio comprova a importância do suprimento de potássio para a planta, por intensificar a massa de forragem.

The objective of this experiment was to evaluate the effects of nitrogen doses (0, 100, 200, 300, and 400 kg ha-1 year-1), with or without dolomitic lime covering application, on the potassium (K) soil content at depths varying form 0 to 5, 5 to 10, and 10 to 20 cm, and the potassium concentration in the plant. The experiment was carried out in a rhodic ferralsol with a slightly rolling relief, in a 5 × 2 factorial arrangement, in a complete randomized block design, with four replications. Nitrogenated fertilization caused a linear increase in the potassium concentration in the plant and also in the mineral content in the 0-5 cm soil layer. An effect of competitive inhibition occurred between the potassium and calcium absorption, and potassium and magnesium absorption. Although a significant fraction of potassium returned to the soil surface layer through the forage residue due to the increase in dry matter production caused by nitrogenated fertilization, the increase in the potassium concentration in the plant due to the doses of nitrogen demonstrated the importance of considering the potassium supply to the plant, when the forage mass is intensified through nitrogenated fertilization.

O manejo do pastejo permite que sistema com base na utilização de pastagem propicie altos rendimentos por animal e por área. Para isto, devem-se utilizar critérios de manejo com intuito de controlar, simultaneamente a qualidade e a quantidade de forragem e manter a sustentabilidade do sistema. A intensidade de pastejo é dinâmica, jamais permanece a mesma, mudando com a taxa de consumo pelos animais e também pelo crescimento das plantas, variando de hora a hora e dia a dia, por isso deve ser controla sistematicamente. Neste cenário, o consumo de forragem parece ser o fator que mais explica as variações no desempenho animal em relação a qualidade da forragem. A suplementação da dieta dos animais em pastejo com concentrado permite aumentar o desempenho de animais, reduzindo a idade de abate ou a da primeira cria. Contudo, as características nutricionais do suplemento devem variar em função da quantidade e da qualidade da forragem ofertada. Ao suplementar a dieta dos animais em pastejo com energia e proteína, pode-se manejar pastos mais baixos em relação a suplementação apenas com sal mineral, sem que ocorra redução da densidade populacional de perfilhos. Estas estratégias de manejo podem reduzir a probabilidade de degradação do pasto. Desta forma, a suplementação da dieta de animais permite aumento na capacidade suporte do pasto.

The grazing management system based on the intensive pasture utilization result in a high animal and area yield. In order to that to be possible, it should be used a management criteria aiming to control, simultaneously the quality and the amount of forage, maintaining the sustainability of the system. The grazing intensity is dynamic, it never keeps the same status, it can be changed with the animals rate intake, and also by the plants growth, changing every hour and day, due to that, it should be controlled systematically. In this scenery, the forage intake is the main factor which explains the variations in the animal performance in relation to the forage quality. Energy and protein supplementations of the grazing animals increase performance, reducing slaughter and the first birth age. However, the nutritional characteristics of the supplement should vary in function of the amount and quality of the forage allowed. Pastures grazed by supplemented animals can be managed at a lower height, compared to those grazed by animals supplemented with only mineral salt, without reducing the tillers population density. These management strategies can reduce the probability of future pasture degradation. Thus, supplementation of the diet of the grazing animals can increase the pasture carrying capacity.

O experimento foi conduzido na UNESP - Jaboticabal com o objetivo de obter informações sobre o rendimento de matéria seca (RMS) e composição química das forrageiras de inverno, aveia preta (Avena strigosa Schreb) e triticale (X Triticosecale Wittmack), em plantio direto sob palhada de área com milheto (Pennisetum americanum (L.) K. Schum.) ou híbrido sorgo sudão (Sorghum bicolor (L.) Moench x Sorghum sudanense (Piper) Stapf) submetidas a pastejo. A forragem foi rebaixada por vacas da raça Holandês. O delineamento experimental utilizado foi em blocos casualizados, em arranjo de parcelas subdivididas, sendo analisado nas parcelas as espécies forrageiras e nas sub-parcelas as épocas de pastejo, com quatro repetições. Os tratamentos testados foram: AS: Aveia Preta sobre palhada de sorgo; AM: Aveia preta sobre palhada de milheto; TS: Triticale sobre palhada de sorgo; e, TM: Triticale sobre palhada de milheto. As pastagens apresentaram RMS semelhantes e, em relação às épocas de avaliação observou-se menor rendimento no segundo corte. Foram observados maiores teores de PB e de FDA na forragem colhida no primeiro corte e de hemicelulose no segundo corte, enquanto os valores de FDN não foram diferentes. A forragem de triticale apresentou menor conteúdo de PB e maiores teores de constituintes da parede celular.

The research was carried out at UNESP - Jaboticabal to evaluate the dry matter yield (YMP), chemical composition of the cool season forage species: oat (Avena strigosa Schreb) and triticale (X Triticosecale Wittmack) no-till seeding in annual summer species cultivated area with pearl millet (Pennisetum americanum (L.) K. Schum.) or sorghum-sudangrass hybrid (Sorghum bicolor (L.) Moench x Sorghum sudanense (Piper) Stapf). The forage was grazed by Holstein cows in rotational stocking system. It was used the completely randomized outline in split plot scheme with four replications. In the first experiment the following treatments were evaluated: AS - oat no-till seeding in sorghum-sudangrass hybrid stubble, AM - oat no-till seeding in pearl millet stubble, TS - triticale no-till seeding in sorghum-sudangrass hybrid stubble, and TM - Triticale no-till seeding in pearl millet stubble. The forages presented similar dry matter evaluation, however the YMP decreased on the second evaluation. It was observed highest crude protein, ADF on the first yield and hemicellulose on the second evaluation. The harvest time did not affect the forage NDF content. Triticale showed lower CP and higher cell wall content compared to the oat forage.

Conduziu-se o experimento na UNESP-Jaboticabal no período de inverno-primavera-verão de 2001-2002, com objetivo de determinar a massa seca total da forragem, composição botânica, relação lâmina foliar/colmo+bainha e variação na produção das misturas no capim-Tifton 85 exclusivo e sobressemeado com espécies de inverno e verão. Os tratamentos foram: milheto (Pennisetum americanum (L.) Leeke)+aveia preta (Avena strigosa Schreb); híbrido de sorgo Sudão (Sorghum bicolor (L.) Moench x S Sorghum sudanense (Piper) Stapf) (AG2501)+aveia preta, sobressemeados nas áreas de Tifton-85 (Cynodon nlemfuensis Vanderyst x Cynodon dactylon (L.) Pers) em 19-06 (época 1) ou 02-07-2002 (época 2) e Tifton 85 (Testemunha). O delineamento experimental o de foi blocos ao acaso. O AG2501 apresentou pequena participação na composição botânica e não se observou a presença do milheto no experimento. A massa total de forragem nas avaliações 1 e 2,-época 1 de semeadura, foi 63% maior quando comparada com a época 2 de semeadura. Nas demais avaliações, foram observadas produções semelhantes. Na época 2, observou-se maior participação de forrageiras de aveia em relação a avaliação 1. A relação lâmina foliar/colmo+bainha decresceu com as sucessivas avaliações em decorrência da composição botânica presente no momento da avaliação.

The experiment was conducted at UNESP-Jaboticabal during the 2001-2002 winter-spring-summer periods to evaluate the herbage mass, botanical composition, dry matter production of mix pastures, and leaf:sheat-stem ration of Tifton 85 or overseeding with annual winter or summer species. The treatments were: pearl millet (Pennisetum americanum (L.) Leeke) plus bristeal oat (Avena strigosa Schreb); sorghum sudan grass (Sorghum bicolor (L.) Moench x Sorghum sudanense (Piper) Stapf) (SS AG2501 C) plus bristeal oat, overseeded on Tifton 85 area on 06/19/02/04 , or 07/02/02, and Tifton 85, conducted in a randomized block design. The AG2501 contributed with a small participation in the botanical composition and the presence of millet in the experiment was not observed. Highest herbage mass at first and second evaluations related to first seeding time was 63% higher compared to the second seeding time. The herbage mass were similarThe production in the other evaluations were similar. On the second seeding time, it was observed highest oat species in relation to the first seeding time. The leaf:sheat-stem ration decreased during the experiment due to the pasture botanical composition changes.

O objetivo deste trabalho foi avaliar a degradabilidade ruminal da matéria seca, da fibra em detergente neutro, da fibra em detergente ácido e da proteína bruta da alfafa (Medicago sativa), aveia-preta (Avena strigosa), leucena (Leucaena leucocephala) e guandu (Cajanus cajan). Amostras de 3 g das forragens foram incubadas no rúmen de três novilhos por períodos de 0, 6, 12, 24, 36, 48 e 72 horas. As degradabilidades efetivas da matéria seca da alfafa e da aveia, para a taxa de passagem de 5% por hora, foram elevadas (acima de 60%). A leucena e o guandu apresentaram valores inferiores, 50,9 e 56,0%, respectivamente. A partir de 24 horas de incubação, a aveia se destacou com maior desaparecimento da fibra em detergente neutro e da fibra em detergente ácido, e ainda apresentou as mais elevadas taxas de degradação efetiva destas frações. A aveia foi a forragem que apresentou maior degradabilidade da matéria seca, da fibra em detergente neutro, da fibra em detergente ácido e da proteína bruta no rúmen. O guandu, entretanto, foi a forragem com as piores taxas de degradação.

The objective of this work was to evaluate ruminal degradability of dry matter, neutral detergent fiber, acid detergent fiber and crude protein of alfalfa (Medicago sativa), black oat (Avena strigosa), leucaena (Leucaena leucocephala) and pigeon pea (Cajanus cajan). Samples of 3 g of forages were incubated in the rumen of three steers for 0, 6, 12, 24, 36, 48 and 72 hours periods. The dry matter effective degradabilities of alfalfa and oat, for a passage rate of 5%/hour, were high (over 60%). However, leucaena and pigeon pea showed lower values, 50.9 and 56.0%, respectively. From 24-hour incubation period on, the oat presented the highest neutral detergent fiber and acid detergent fiber disappearance and showed the greatest effective degradation rates of these fractions. The oat was the forage with the highest dry matter, neutral detergent fiber, acid detergent fiber and crude protein ruminal degradability. Pigeon pea, however, was the forage that showed the worst degradation rates.

Conduziu-se o experimento na UNESP-Jaboticabal, no período de inverno-primavera-verão de 2001-2002, objetivando determinar os teores de proteína bruta (PB), parede celular (FDN, FDA, lignina, celulose e hemicelulose) e a digestibilidade in vitro da matéria orgânica (DIVMO) no capim-Tifton 85 exclusivo e sobressemeado com aveia preta, milheto e sorgo-sudão. Os tratamentos testados foram: milheto+aveia preta; AG2501C+aveia preta, sobressemeados nas áreas de Tifton-85, em 19-06 ou 02-07-2002, e capim-Tifton 85 (Testemunha). O delineamento experimental foi de blocos casualizados, com três repetições. Os teores de PB foram maiores na primeira avaliação quando comparada às demais. Observou-se aumento nos teores de FDN, FDA e lignina, e comportamento inverso nos valores de DIVMO, em relação aos períodos de crescimento, nas duas épocas de semeadura. Os teores avaliados de PB, parede celular e DIVMO apresentaram variação em função da composição botânica e morfológica, no decorrer das avaliações e épocas de semeadura.

The experiment was conducted at UNESP-Jaboticabal on the 2001-2002 winter-spring-summer period to evaluate the crude protein, cell wall (NDF, ADF, cellulose, hemicellulose and lignin) contents, and in vitro organic matter digestibility (IVOMD) of the Tifton 85 alone or overseeded with annual species (oat, pearl millet, and sorghum Sudan grass-SS). It was evaluated the followings treatments: pearl millet plus bristal oat; SS AG2501 C plus bristeal oat, overseeded on Tifton 85 area on 06/19/02, or 07/02/02, and Tifton 85. The data were analyzed according a randomized block design with three repetitions. The CP was highest on the forage harvested at the first evaluation. The cell wall content increased, and IVOMD decreased, in relation to the plant development in booth seeding time. The CP, cell wall contents, and IVOMD changed during the evaluations and seeding time due to the botanical and plants morphological composition.

Para avaliar o efeito de um inoculante microbiano sobre a estabilidade aeróbica de silagens de capim-elefante (Pennisetum purpureum, Schum) pré-seco, foi conduzido um experimento na UNESP, Campus de Jaboticabal. O capim foi cortado com 96 dias de crescimento, permanecendo sob ação do sol, por aproximadamente 5 horas para o emurchecimento. Foram confeccionados silagens, em barricas plásticas de 200 L de capacidade, que receberam (CI) ou não (SI) o inoculante no momento da ensilagem. Para o estudo da deterioração aeróbica, na abertura dos silos (T0), cada barrica foi subdividida em três profundidades e as silagens expostas ao ar em um sistema, usado para a determinação de CO2, por 2 (T2), 4 (T4), 6 (T6) e 8 (T8) dias. A silagem da camada superficial não apresentou diferenças no valor de pH e contagem de leveduras, em relação à da camada intermediária, porém ambas apresentaram valores superiores à camada mais profunda. O teor de N-NH3 da camada superior foi menor que o da intermediária e profunda, que não diferiram entre si. A interação significativa entre inóculo e tempo de exposição mostrou que nos primeiros tempos de aeração (T0; T2 e T4) as silagens inoculadas não diferiram das controle em termos de pH, teor de N-NH3 e contagem de bolores, mas com avanço do tempo (T6 e T8) passaram a apresentar menor valor de pH, menor contagem de fungos e tendência a menor produção de CO2, indicando menor velocidade de deterioração após seis dias de exposição aeróbica.

An experiment was carried out at UNESP, Jaboticabal Campus to evaluate the effect of a microbial inoculant on aerobic stability of wilted grass silage (Pennisetum purpureum, Schum). The grass was cut with 96 days of growing, remaining under sun action 5 hours to wilt. Silages were made in plastic silos, 0.2m³ capacity, that received (CI) or not (SI) inoculant at the ensilage time. For the study of aerobic deterioration, each silo was subdivided in three levels and the silages were exposed in a system, used to evaluate CO2 production, for 2 (T2), 4(T4), 6(T6) and 8(T8) days. Surface silage had higher pH value, lower NH3-N content, and higher yeast count than middle and bottom silages. The significant interaction between inoculation and aeration stage, shown that at earlier stages (T0, T2 and T4) there was no difference between treated and control silages in pH, N-NH3 and mold count, but at later stages (T6 and T8), inoculated stages had lower pH value, mold count and tended to a lower CO2 production, showing a lower deterioration speed after 6 days of aerobic exposure.