Suchergebnisse

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.

The Brazilian livestock activity is undergoing constant evolution, and aiming at its maximum efficiency, it is necessary to have available to the animals food in quantity and quality all the year. To this end, the cultivation of winter forage is carried out. The present study aimed to evaluate the productive and qualitative agronomic traits of ryegrass forage. The experiment was a randomized block design in a 3 x 2 factorial arrangement consisting of six treatments, three plant stands (525, 1050 and 2095 plants m-2) associated with two successive cutting times (vegetative and full vegetative), and four repetitions. There was no interaction between population stand and cutting times for the variables studied. The stand of 525 plants m-2 had a higher participation of green leaves (50.52 %), higher digestibility of the whole plant dry matter (84.81 %) compared to the stands of 1.050 and 2.095 plants m-2, and dry biomass production per unit area equivalent to the others (6087, 7243 and 6989 kg ha-1, respectively). The first harvest season presented higher participation of green leaves and better leaf/stem ratio, 58.62 % and 3.41 % respectively, as well as higher digestibility of green leaves (77.26 %) and stem (80.82 %).

The objective of this study was to evaluate the productive performance, ingestive behavior, apparent digestibility of the diet, rectal temperature, superficial thermography of skin and hull, and the carcass traits of heifers finished in confinement under the effect of inclusion of live yeasts (Saccharomyces cerevisiae as probiotic) in the diet. The treatments were: Control: diet without the inclusion of live yeasts, and Yeast: diet with the inclusion of live yeasts (7 g animal day-1, at the concentration of 107 CFU g-1. The diets were composed of corn silage at a constant forage: concentrate ratio of 50: 50, on a dry matter basis. The experimental design was completely randomized, composed of two treatments and nine replicates, wherein each replicate was represented by a stall with two animals. Thirty-six heifers, ½ blood Angus, from the same herd, with an average age of 11.9 months and an initial average body weight of 317 kg, were used in the experiment. Supplementation of live yeasts in the diet for finishing heifers proved to be efficient in the feedlot finishing phase because it provided improvement in the apparent digestibility of DM. In relation to the productive performance, ingestive behavior, rectal temperature, superficial thermography of skin and hull and carcass traits, no statistical difference was found between the treatments. The animals have already come from the property adapted to the feedlot system, defining small challenge against the presence of live yeasts included in the experimental diet, justifying the lack of expression on some results obtained.

The experiment was conducted at the Animal Production Center (Núcleo de Produção Animal – NUPRAN) of the Center for Agrarian and Environmental Sciences of the Universidade Estadual do Centro-Oeste - UNICENTRO - CEDETEG Campus, Guarapuava, State of Paraná. This study aimed to evaluate biomass production, plant physical composition, chemical composition and dry matter contents of the plant and structural components of forage corn. The experiment was carried out in 5x5 factorial with five planting densities (80, 160, 240, 320 and 400 thousand plants ha-1), harvested in 5 times (40, 50, 60, 70 and 80 days after planting). The harvesting time caused a statistical difference for all parameters, and the planting densities factor only caused statistical difference in leaf participation and dry biomass production. There was no interaction for any of the parameters evaluated. Forage corn, harvested in the vegetative stage, can be a great ally of the rural producer, since it presents high potential for food production with high nutritional value in a short period of time, and in significant amount with production of up to 14,720 kg ha-1 dry biomass reached at 80 days of cycle with 320 thousand ha-1, freeing the soil for the production of another crop.

The objective of this experiment was to evaluate the in situ dry matter degradability and in situ crude protein degradability of soybean meal subjected to different treatments (thermal, chemical, tannins or saponins). The treatments were: conventional soybean (CON); soybean expeller (EXP); lignosulfonate-treated soybean meal (LIGS); condensed tannin-treated soybean meal (CTAN); hydrolysable tannin-treated soybean meal (HTAN) and Yucca schidigera extract-treated soybean meal (YUC). Samples of 5 g soybean meal were packed in nylon bags and incubated in the rumen of 2 fistulated cattle for seven incubation times (0, 3, 6, 9, 12, 18 and 24 hours), in sequence were washed, dried and weighed. The ruminal kinetics parameters were calculated, and the experiment was completely randomized, with six treatments, four replicates each, with duplicates. The EXP and LIGS treatments showed lower crude protein disappearance (CPD) within 12 hours, the CON, HTAN and YUC treatments had the highest CPD, and the CTAN presented an intermediate value (41.84%) (P < 0.05). EXP had the lowest fraction "a" (soluble) of crude protein (CP) (10.1%) followed by LIGS and CTAN (average of 14.82%). EXP and LIGS had the highest rumen undegradable fraction of CP (57.35 and 51.62%), respectively. In addition, ruminal disappearance rates of dry matter and CP of the treatments ranged from 2.17 to 1.36% h-1 and from 2.63 to 1.2% h-1, respectively. The most efficient treatments to reduce ruminal protein degradation were EXP, LIGS and CTAN.

The goal of the present study was to evaluate the biomass and grain yield, the morphological and chemical composition, production costs and the ruminal disappearance of the whole corn plant and grain-free corn plant harvested at different reproductive stages. The experimental design was completely randomized, consisting of six treatments, where each treatment corresponded to a stage of corn maturity. The advance of plant cycle promoted an increase in dry biomass and grain yields per unit area, reducing production costs. Higher participation of grains and lower participation of structural components promoted a reduction in NDF and ADF, with the lowest values in dough grain (R4) and dent grain (R5) stages. The advancement of stages promoted an increase in production and a reduction in costs, but significantly reduced the quality of grain-free plants, increasing the NDF, ADF and ADL; but R4 and R5 presented NDFd of 84.80 % and 82.79 %, respectively, showing to be a good quality fiber. R4 stage had the highest rumen disappearance values after 24 and 48 hours of incubation. Based on chemical data, ruminal disappearance, ruminal degradation kinetics of the whole corn plant and without grains, the R4 stage of the evaluated hybrid is the stage at which the plant had the best quality, representing the appropriate stage to harvest the material for making silage, aiming at the production of a silage with good chemical quality.