Suchergebnisse

The objective of this study was to evaluate the production and chemical composition of silages of grass Tanzania and corn, grown single or intercropping. The experiment was conducted at UTFPR Câmpus Dois Vizinhos in the period between October 2011 and July 2012, a 600 m² area. The treatments were: TMI - single corn, TMT - corn and grass Tanzania consortium at the time of sowing, TT - Tanzania grass single, TT32 - grass Tanzania silage to 32% dry matter (content similar to that of corn). The experimental design a randomized block design with four treatments and five replications. Agronomic evaluations were performed 120 days after planting, as follows: number of linear-1 plants metro, plant height and ear insertion and number of ears.plants-1. In the grass we evaluated canopy height, where it was held the botanical separation in green leaves, dried and stem. Silage started being held in 100 mm PVC pipe (mini-silos) kept sealed for 60 days. At the time of opening of the silo were determined the following parameters: DM, pH, total loss of DM (PDM), specifies mass (SM), dry matter recovery indices (IRDM), losses gas (LG), and size particle. Chemical analysis of the results of OM, MM, ADF were higher for TMI treatments, TT and TT, respectively. CP and LIG had superior results for the treatments containing grass. Corn intercropping with grass Tanzania silage provides more crude protein and lignin compared to exclusive corn silage without damaging the crop yield. Silage maiden Tanzania has higher levels of ADF and crude protein as well as increased production of dry matter than corn silage. The grass Tanzania should be harvested with 30% DM as presented better pH values, higher dry matter recovery rate, less loss of gas as well as increased production of dry matter that Tanzania harvested at the same age corn.

The objective of this study was to define the input height to grazing and evaluate forage production of Italian ryegrass (Lolium multiflorum Lam.) cv. Barjumbo and cv. Common associated or not with oat black forage (Avena strigosa Schreb) cv. IAPAR 61, submitted to two post-grazing. Treatments consisted of a 4x2 factorial design, totaling eight treatments with three replications, being evaluated common and Barjumbo ryegrass, single and mixed with black oat in two highs of post-grazing residue: High: 50% of input height; Low: 30% of input height. Single Common ryegrass and combined with black oat obtained higher production than Barjumbo cultivate, and greater accumulation rate only when intercropped with black oat. Leaf blades production did not differ among cultivars. Stems production was low to Barjumbo cultivar. Black oat production was higher when associated with Barjumbo. Input height to Italian ryegrass cultivars with 95% light interception was 26.86 cm to Barjumbo and 28.75 cm to common cultivar, and when combined with black oat 34.01 cm and 32.48 cm, respectively.

Phosphorus (P) is one of the most limiting mineral elements for biomass and grain production in tropical soils. This study was undertaken to assess the influence of P on herbage accumulation (DM) and the nutritive value of forage sorghum (Sorghum bicolor) and black oat (Avena strigosa) in succession. Evaluated treatments were P fertilization levels of 0, 50, 100, 150 and 200 kg of P2O5 ha-1 distributed in a randomized complete block design with three replicates. The treatments were applied at sorghum seeding in the summer 2010/2011 and 2011/2012. Black oat was seeded following sorghum in 2011 with no additional P fertilization. Herbage production and its nutritive value were assessed by successive cuts. The greatest sorghum DM yields were obtained at the highest phosphate level tested (200 kg P2O5 ha-1), with residual response in subsequent black oat. There was no effect of P fertilization levels on the nutritive values of both crops, considering crude protein (CP) levels, in vitro dry matter digestibility (IVDMD), neutral detergent fiber (NDF) and acid detergent fiber (ADF), what demonstrates that P addition has no effect in forage nutritive value, especially when the soil P levels are classified as medium or high. The plant P recovery efficiency decreased when increasing P fertilization levels for both sorghum and black oat. The level of 50 kg P2O5 ha-1 year-1 presented the greatest P recovery by plants, which supports the idea of less fertilizer use with more efficiency.

This study aimed to assess forage production, animal performance, and the chemical composition of Tanzania grass pasture fertilized with 50, 100, 200, and 400 kg ha-1 of nitrogen. The variables analyzed were: leaf mass, daily accumulation rate, leaf/stem ratio, average daily gain, stocking rate, live weight gain per unit of area crude protein, neutral detergent fiber, and in vitro dry matter digestibility of leaves. The pasture management maintained the pasture height at 50 cm by using a continuous grazing method with the adjustment of stocking rate. The experimental design was a randomized block with three replicates. The leaf mass increased linearly in response to nitrogen, with an increase of 1003 kg (34%) observed between a nitrogen content of 50 and 400 kg ha-1. Nitrogen did not affect the average daily gain, but increased the stocking rate and live weight gain ha-1. The value of crude protein and neutral detergent fiber were higher with increased nitrogen levels, whereas the leaf digestibility did not affect nitrogen use. The comparison of 50 and 400 kg ha-1 levels indicated that there was an average increase of 19.2% in the leaf crude protein. The increased application of nitrogen fertilizer in Tanzania grass improved the chemical composition and animal performance; with regard to studied variables, the dose of 200 kg ha-1 resulted in the greatest improvement.

The objective of this study was to evaluate the weight of the empty body and non-integrant components of Holstein calves carcass, kept in confinement system or pasture, slaughtered at different weights. We used 43 Holstein calves, entire, age and initial body weight of approximately 58 days and 57 kg, distributed entirely at random in confinement or cultivated pasture. In feeding systems, it was pre-stipulated four slaughter weights (SW - 140, 180, 220 and 260 kg of live weight). In confinement, were provided corn silage and concentrate based on corn meal and soybean meal, in the ratio 40:60. The other animals in ryegrass pasture, followed by pearl millet, were fed based in supplementation of corn bran and soybean meal to 1% of live weight. The EBW showed linear growth with increasing slaughter weight (SW), as well as income from hot and cold carcass and there was no effect in relation EBW/ SW. The leather, the scraps, the head, the legs, as well as the sum of external components showed growth in its absolute weight as the weight increased at the slaughter of animals. In relative terms, the hot and cold carcass yields were inversely correlated with the relative weights, as well as external components (- 0.68 and - 0.81), the heart (- 0.35 and -0, 38) lungs (- 0.53 and - 0.53), the sum of the gastrointestinal tract (-0.75 and - 0.77), the sum of vital organs (- 0.71 to - 0.75) respectively in feedlot and pasture. This is due to the different ages that the animals were slaughtered (200; 237; 251 and 263 days of age), due to pre-stipulate weights. The absolute weights of heart, kidney, lungs, liver, spleen, gall bladder, reproductive tract and gastrointestinal tract accompanied the increase in weight at animal's slaughter. However, when grouped, showed no difference related to the increase in weight at slaughter. The differences presented by the liver, trachea and spleen were sufficient to alter the absolute and relative weights of the set of internal components, where the animals finished on pasture had higher weight. The animals finished on pasture had higher absolute weights (0.48 against 1.18 kg) and relatives (0.31 and 0.79%).

The objective of this work was to evaluate the effects of irrigation and nitrogen fertilization on the bromatological quality, forage production, and botanical and structural composition of Tifton 85 (Cynodon sp.) pastures overseeded with black oat (Avena strigosa). Four treatments were evaluated in a 2 × 2 factorial scheme (irrigated and non-irrigated × fertilized and non-fertilized), with three replicates, in a completely randomized design. In irrigated paddocks, the irrigation system was activated when the soil matric potential reached a value equal to, or higher than, 10 kPa and 135 kg N ha-1 was applied to fertilized paddocks, divided into four applications. The forage mass pre- and post-grazing, total forage production, and the botanical, structural, and bromatological composition of the pastures were evaluated. No interaction was observed between the irrigation and nitrogen fertilization factors for any of the variables and no significant differences were observed in forage mass between pre- and post-grazing or in Tifton leaf and stem percentages. Nitrogen fertilization had a significant effect on forage production, which was 2626.41 kg dry matter (DM) ha-1 higher in fertilized pastures than in unfertilized pastures. In addition, fertilization resulted in a lower percentage of dead material (6.66%), higher percentage of oat leaves (30.84%), higher leaf:stem ratio (1:45), higher crude protein content (24.13%), lower levels of neutral detergent fiber (NDF) (64.57%) and acid detergent fiber (ADF) (32.86%), and higher in vitro dry matter digestibility (73.01%) than in unfertilized pastures. The use of irrigation did not influence total forage production, however, it resulted in pastures with lower NDF (65.97%) and ADF (33.54%), and higher in vitro dry matter digestibility (73.48%) than unirrigated pastures. Nitrogen fertilization produced improvements in pasture structure, associated with higher dry matter yield and bromatological quality, while irrigation only produced pastures with lower fiber content and greater digestibility.

Essential oils and enzymes are alternatives to feed additives for ruminants that aim to replace the use of ionophores and improve animal performance, but their mechanisms of action are different. Therefore, the present study aimed to verify if there is a synergistic effect in the combined use of enzymes carbohydrates and essential oils on the performance, ingestive behavior and carcass traits of steers fed a high-energy diet. During the finishing period of 78 days, 40 steers were assigned to four treatments: CON- control; ENZ- enzymatic complex; EO- essential oil blend; ENZ+EO - enzymatic complex combined with essential oil blend. Regardless of the feedlot periods, the ENZ+EO treatment caused a reduction in the dry matter intake (12.48%) compared to the control. The ENZ+EO treatment resulted in the lowest mean fecal output and, consequently, the highest dry matter digestibility (DMD) and starch digestibility (SD), compared to the other treatments. Animals that received EO and ENZ+EO in the diet spent more time in feeding. As for the number of times animals visited the feeding trough, the highest values were presented by the animals in the EO, ENZ and ENZ+EO treatments. For the carcass parameters, only the subcutaneous fat thickness on the rib was significantly different between treatments, with the highest values obtained by adding EO and ENZ+EO (8.80 and 8.10 mm respectively). Thus, the combination of carbohydrate enzymes and essential oils proved to be synergistically beneficial in relation to better use of nutrients and productive performance of feedlot steers.

The aim of this study was to evaluate the forage production, nutritional value (including protein fractions), and morphogenic characteristics of African star grass on nitrogen fertilizer in a single application and split applications of two and four, under mob grazing. The study was conducted on a 1.5 ha area with well-established African star grass (Cynodon nlemfuensis). The area was divided into 18 paddocks of 400 m2. for three treatments and six replications that were assigned through a randomized block design. The treatments were: Nap1 =Single N application; Nap2= split into two N applications; and Nap4: split into four N applications. Fertilizer application was 200 kg ha-1 of N in topdressing. Pasture was monitored weekly by sward height. Grazing began when the forage reached between 25 and 30 cm in height and ceased at 10 cm. In almost all months evaluated, Nap1 recorded the highest forage production, daily accumulation rate and available forage mass. Some morphogenic characteristics changed between the fertilization strategies, particularly in the months with greater water availability. The chemical composition did not fluctuate between treatments. African star grass can be fertilized with a single application of nitrogen at 200 kg ha-1 to attain greater forage mass and proportion of leaves, without any changes to the chemical composition and nitrogen fractions. These components were modified by the vegetative phase of the forage.