Luciano Fernandes Sousa

Nutritional evaluation of “Braquiarão” grass in association with “Aroeira” trees in a silvopastoral system

This study aimed at evaluating the influence of a silvopastoral system (SPS) composed of “Aroeira” trees (Myracrodruon urundeuva) on the nutritional value of Brachiaria brizantha cv. Marandu forage grass over the rainy season. The experiment was conducted in the SPS located in the “Cerrado” biome in Lagoa Santa County, Minas Gerais state, Brazil, in the agricultural year of 2004–2005. It was evaluated the influence of “Aroeira”, whose density in the area was 140 trees/ha, on the following parameters of the B. brizantha cv. Marandu forage grass: forage mass harvest above stubble height, morphogenic attributes, bromatological composition and nutritional value. The effects of “Aroeira” trees on the micro-climatic conditions were also evaluated. The experiment adopted a randomized block design with five blocks (cutting seasons), two treatments (a shaded pasture—B. brizantha cv. Marandu shaded by M. urundeuva—and a pasture in full sun—B. brizantha cv. Marandu in full sun), and three replicates. The tree component, composed of the tree species M. urundeuva in the experimental density adopted, increased dry matter and crude protein of the forage mass harvest above stubble height, without affecting the concentration of neutral detergent fibre or acid detergent fibre, thus causing dry matter and organic matter in vitro degradability as well as effective degradability of the forage grass to remain the same as those obtained in full sun. Therefore, the results of this study show the possibility of using trees and grass to increase both animal production and environmental services.

Replacement of corn by babassu mesocarp bran in diets for feedlot young bulls

Nutrient intake and digestibility and productive performance of 30 feedlot young bulls fed diets containing babassu mesocarp bran in replacement of corn were evaluated. Animals were distributed in a completely randomized design with five levels of replacement of corn by babassu mesocarp bran (BMB): 0, 250, 500, 750 and 1000 g/kg of dry matter, and six replications. The dry matter (DM) intake in kg/day, g/kg body weight (BW) and g/kgBW0.75 increased as the corn was replaced by BMB. The intake of neutral detergent fiber (NDF) and crude protein (CP) increased linearly, whereas the intake of non-fibrous carbohydrates (NFC) had quadratic behavior. The digestibility of DM, CP, NDF and NFC and the total digestible nutrients (TDN) showed quadratic behavior with points of minimum digestibility of 850.0, 638.0, 867.0, 638.0 and 833.0 g/kg dry matter of replacement of corn by BMB, respectively. The final weight (476.82 kg) and average daily gain (1.55 kg/day) were not affected by experimental diets. The feed efficiencies of DM and CP decreased with increase in the levels of BMB, but the feed efficiency of TDN was not changed. Babassu mesocarp bran enables satisfactory performance, and depending on the price and opportunity cost, it can be utilized in the feeding of feedlot cattle totally replacing the corn of the diet.

NUTRIENTS INTAKE AND DIGESTIBILITY OF PALM KERNEL CAKE IN SHEEP DIET

The aim of this study was to find the optimum inclusion level of palm kernel cake in sheep diet. We used 18 castrated rams, fed diets with inclusion levels of palm kernel cake of 0%, 7.5%, 15% and 180 VISONÁ-OLIVEIRA, M. et al. Cienc. anim. bras. v.16,n.2, p. 179-192 abr./jun. 2015 22.5% of the total diet. Animals were housed in metabolic cages for 21 days. Data were subjected to regression study with 5% significance for equations and regression coefficients. The inclusion of palm kernel cake caused reduction in DM, hemicellulose, NDF, CP, TDN, TC and MM (P <0.01) and no significant differences in cellulose, ADF and NFC (P> 0.05). The intake of EE and lignin increased (P<0.01). The fiber content of the diets added to the consumption of lignin by the animals caused reduction in digestibility of GE and all analyzed nutrients (DM, CP, hemicellulose, NDF; P<0.05). There was reduction in metabolizability of the diets due to increased GE of feces (P <0.01). Nitrogen balance was positive in all treatments. The inclusion of palm kernel cake above 7.5% in sheep diet causes reduction in DMI and digestibility of nutrients with possible performance losses, especially in high-performance animals.

Productive performance and blood parameters of bulls fed diets containing babassu mesocarp bran and whole or ground corn

The objective of the present study was to evaluate the effects of corn milling and the inclusion of babassu mesocarp bran (BMB) on productive performance, digestibility of dietary nutrients, and blood parameters of dairy crossbred (Holstein-Gyr) bulls finished in confinement. Twenty-four bulls were fed four different experimental diets, containing two levels of inclusion of BMB (0 and 41.24%) and corn supplied in two different forms (ground and whole), for 98 days (77 days of data collection and 21 days of adaptation). The intakes and digestibility coefficients of the dry matter (DM) and nutrients were determined. There were no significant interaction effects of the BMB inclusion level and the form of corn used on the performance and digestibility variables. The intakes of DM, crude protein (CP), and neutral detergent fibre (NDF) increased with the inclusion of BMB in the diets. However, the inclusion of BMB in the diets decreased the ether extract intake, the NDF apparent digestibility, and the feed efficiency of DM and CP. Dry matter and NDF intakes also increased with the use of ground corn in the diet, which promoted an increase in the intake of total digestible nutrients (TDN), digestibility of non-fibrous carbohydrates, and average daily gain. However, the supply of ground corn reduced the feed efficiency of TDN. The remaining measured variables did not vary with the tested diets. The levels of plasma protein and albumin remained normal, but glucose concentrations were always high, irrespective of the tested diet. The form of corn supplied and the level of BMB inclusion had a significant interaction effect on the levels of triglycerides, urea, aspartate aminotransferase, and alkaline phosphatase. Babassu mesocarp bran can be included up to 41.24% in the diet of confined bulls without a negative effect on the animal weight gain. Corn should be supplied ground because this form improves the performance of crossbred bulls

Babassu mesocarp bran levels associated with whole or ground corn grains in the finishing of young bulls: carcass and meat characteristics

The objective of this study was to evaluate the effect of grinding corn and inclusion of babassu mesocarp bran (BMB) in the diet of crossbred dairy young bulls finished in feedlot on their carcass and meat characteristics. Twenty-four young bulls were fed four experimental diets containing two BMB inclusion levels (0 and 41.24%) and corn in two forms of processing (ground and whole grains) for 98 days, and then slaughtered in a commercial packing plant. Among the quantitative carcass characteristics, there was interaction only in fat trimmings/whole hot carcass weight and cold carcass yield. The whole hot carcass and hot carcass weights showed reduced means with the use of whole corn. The other quantitative variables were not separately affected by BMB inclusion levels or by the form corn was processed. There was interaction between the factors for pistol cut weight, edible portion and weight of the cuts of the pistol cut, in which the use of whole corn and BMB promoted reduction in the mean values. The use of the whole corn grain reduced the participation of flank cut and elevated the participation of the bone fraction in the carcass. Inclusion of 41.24% of BMB did not change the qualitative meat characteristics, but the use of corn grain resulted in darker meat. The use of whole corn resulted in alteration in the weight of cuts like eye of rump and striploin, which have a high commercial value. There was interaction between factors for the percentages of moisture and minerals of the meat, whereas the crude protein content was affected by the two factors. The use of diets with whole corn or with babassu mesocarp bran may modify the carcass and meat characteristics of finishing crossbred young bulls.

Feeding behavior of crossbred steers fed diets containing babassu mesocarp meal and corn in kernels or ground

The objective of the present study was to evaluate the effect of the use of babassu mesocarp meal (BMM) and corn in different physical forms on the feeding behavior of crossbred young bulls of a dairy breed. Twenty-four crossbred (Nellore vs. Holstein) steers (307.35 kg) were fed four experimental diets containing two levels of inclusion of the babassu mesocarp meal (0 and 412.4 g/kg) and corn in two physical forms (kernels or ground) for 98 days. Data was collected on three days during the finishing phase, with observations every five minutes, for 24 hours. When the activities performed by the animals were evaluated as a function of the period of the day, the physical form of the corn showed interaction with the BMM inclusion level on the time spent feeding and on other activities. When the activities were evaluated over the day, the defecation frequency was affected and decreased as BMM was included. The feeding time was longer at the moments that followed feed supply, whereas the time used for other activities increased during the morning period, regardless of the diet utilized. Rumination and idle times were affected by the period of the day and remained high during the night and morning periods. There was increase in feeding time and dry matter rumination efficiencies and neutral detergent fiber as BMM was added to the diet. The number of rumination chews per bolus, however, decreased as BMB was included. Inclusion of babassu mesocarp meal increases the animal feeding time but the physical form of corn does not change its feeding behavior.

Avaliação nutricional de fenos produzidos com Andropogon gayanus cv. Planaltina

In this study Andropogon gayanus cv. Planaltina hay produced at different ages of growth (56, 84, 112 and 140 days) were used for degradability assay of in vitro dry matter using semi-automated in vitro gas production technique. The data of in vitro dry matter degradation was used for the fabrication of equations and used for parallelism and curve identification comparison tests. The comparison between the A. gayanus hays harvested at different ages of growth by parallelism test showed that degradability in vitro dry matter curves are parallel. The similar curves showed kinetic behavior for in vitro dry matter degradability. When compared, the A. gayanus hays harvested at different ages of growth through the curve identification test, showed that A. gayanus hays harvested between 56 and 84 days are similar and had higher in vitro dry matter degradability. Nutritionally superior A. gayanus hay cut plants are obtained at intervals of 56 to 84 days.

Cinética de fermentação ruminal in vitro da forrageira Brachiaria brizantha cv. Marandu em sistema silvipastoril

The influence of a silvopastoral system composed of Bolsa de Pastor (Zeyheria tuberculosa) on in vitro kinetics of ruminal fermentation of Brachiaria brizantha cv. Marandu was evaluated at Cerrado bioma, in the years 2006 and 2007. The silvopastoral was established in 1982, by natural regeneration of tree species in red-yellow oxisols. The trials on kinetics of ruminal fermentation were carried out in a split-plot design with three replicates. The silvopastoril system and the monoculture of Brachiaria were allocated as plots and the harvest periods as the split-plots. Kinetics of ruminal fermentation in the systems were similar. However, during the rainy season, the forage was highly fermentable in comparison to the transition season. The forage harvested during the dry season showed lower fermentability.

Implementation of Silvopastoral Systems under Nutrient Cycling in Secondary Vegetation in the Amazon

Silvopastoral systems can be implemented in idle secondary forests; however, they may affect nutrient cycling in these ecosystems. This farming practice using babassu palms ( Attalea speciosa Mart.) and Mombasa grass ( Panicum maximum Jacq.) has been little studied, and the nutrient cycling occurred during this practice is yet unknown. The goal of this paper was to detect the leaf litter accumulation, decomposition, and nutrient release occurring in silvopastoral systems in a babassu secondary forest, and compared the results with those of a native forest and of a pasture grown under full sunlight. The data relating to deposition, chemical composition, decomposition, and macronutrient release of leaf litter and pasture litter were evaluated by multivariate analyses. The results showed that forest thinning reduced leaf litter deposition and overall nutrient cycling but had no effect on decomposition rates. Conversely, the presence of grass in the understory promoted increased overall nutrient cycling rates. The cycling in integrated systems occurs more similar to that of forests than that of monocultures. The greater the thinning intensity the more similar the cycling will be relative to that occurring in pastures and in monocultures. The nutrients Ca, Mg, and N were the most affected by thinning. Moreover, the presence of grass in integrated systems provided an increased N and Mg cycling, whereas the thinning reduced Ca cycling. K showed the highest release and return ratio to the soil. Lastly, leaf litter from pasture areas showed higher contents of nutrients, decomposition rates, as well as an enhanced nutrient cycling capacity.

A suplementação com propilenoglicol melhora o metabolismo energético em ovelhas gestantes

The objective was to evaluate the effect of propylene glycol inclusion in water pregnant ewes on energy metabolic parameters. We evaluated 28 pregnant ewes which received various levels of propylene glycol (PG) in water. These sheep were distributed in four treatments (0, 1.5, 3.0 and 4.5% PG) in a randomized design in a split plot design. The highest propylene glycol inclusion (3.0 and 4.5%) in the water caused linear increase in blood glucose concentration throughout the gestational period. The blood glucose concentration in sheep receiving 3% propylene glycol in water increased linearly with the increase in the collection period. On the other hand, for the sheep who received 4.5% of propylene glycol response was quadratic. The addition of propylene glycol in the pregnant sheep of water improves energy metabolic parameters, and the use of this substance it´s very important to minimize the negative energy balance at the end of pregnancy.