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Earth greenhouse gas effect is a natural process that sustains the planet temperature to degrees suitable for life forms to survive. Humans development is shown as the responsible for both, temperature and natural cycle alterations, rise due greenhouse gases capacity in conserve higher temperatures. Studies shows that the temperature will continually increase, and mitigation measures are necessary to allow feed production growth without environmental impact. Production intensification is an efficient way to minimize pollutants emission per kilogram of animal products. Although ruminants advantage of eating fibrous feed, that are not suitable for humans, and the capacity to transform it in superior quality food, grains inclusion in cattle diet decreases environment livestock impact. Beef suckler herds are large responsible for all livestock pollution impact. Integrating intensively reared dairy calves to beef production it's an alternative to decrease livestock impact. Brazilian livestock is a major responsible for greenhouse gas production. The low technology and the poor system intensification, allows the formulation of national measures to decrease the pollutants and also enhance the production. [ABSTRACT FROM AUTHOR]

Pearl millet (Pennisetum glaucum (L.) R.) is an important crop for rainfed production systems and can play a significant role as a feed source for ruminants owing to its high yield and drought tolerance. It is well-established that the maturity stage can influence the chemical composition as well as the nutritional value of crops traditionally used for silage production, although quantitative evidence that this occurs with pearl millet under rainfed conditions is lacking. The current research assessed the agronomic characteristics, ensilability, intake and digestibility of a Brazilian pearl millet cultivar (IPA BULK1-BF) harvested at four different growth stages. Forage was harvested at 35, 50, 65 and 80 days after sowing and ensiled under laboratory and farm conditions. Apparent digestibility of the silages was determined using 24 male lambs. The results showed that dry matter (DM) and panicle and stem proportions increased with the advancement maturity. The silage evaluations showed that DM, total and non-fibrous carbohydrates and lignin concentrations increased, while crude protein, ADF and in vitro DM digestibility decreased with the increase in plant maturity. Additionally, the fermentation characteristics were improved with the increasing maturity. The digestion study showed that intake of DM and N as well as digestibility of DM and fibre fractions decreased, while lignin intake increased. The results obtained for the production of dry and digestible DM, the ratio of plant fractions and fermentation parameters indicate the possibility of harvesting pearl millet forage after 50 days after sowing for silage production in the Brazilian semi-arid region. [ABSTRACT FROM AUTHOR]

The nutritional energy requirements of animals for maintenance and weight gain, such as the energy partition of the diet, were determined in different feeding plans. Fifteen F1 Holstein × Gyr, non-castrated male bovines with a mean initial liveweight of 302 kg were used. The diets were corn silage and concentrate, formulated to enable gains of 100, 500 and 900 g/day, called low, medium and high weight gains, respectively. Tests of digestibility and metabolism were conducted to determine energy losses through faeces, urine and methane emissions. Heat production was determined using respirometry chamber. Net energy for maintenance was calculated as the antilogarithm of the intercept of the regression of the logarithm of the heat production, as a function of the metabolisable energy intake. Retained energy was obtained by subtracting the heat production from the metabolisable energy intake. With the increased consumption of dry matter, there was an increase in faecal and urinary energy loss. Retained energy increased linearly with the metabolisable energy intake. The net energy for gain in the diet did not differ among the treatments, such as the efficiency of use of metabolisable energy for weight gain kg (0.34). The net energy for maintenance was 312 kJ/kg LW0.75, and the metabolisable energy for maintenance was 523 kJ/kg LW0.75. The daily methane production (g/day) increased with the dry matter level and the daily loss represented 5.31% of the gross energy consumption. The determination of the nutritional energy requirements for bovines of different genetic groups and under different feeding conditions allows the appropriate adjustment of feed formulation for each animal category. Knowledge of the energy partition of the diet and methane production allows the development of appropriate nutritional strategies respecting the environment. [ABSTRACT FROM AUTHOR]

Forage cactus is an important dry-season feed source for livestock in semi-arid regions, but in north-eastern Brazil, its contribution is limited by susceptibility to the carmine cochineal [ Dactylopius opuntiae (Cockerell)] insect. New cactus germplasm shows superior agronomic performance, but the nutritive value of this material has not been adequately described. The objective of the current study was to assess the divergence in chemical composition and rate and extent of in vitro degradation of these genotypes. The treatments were 13 spineless cactus genotypes, eight of which were insect resistant types, two semi-resistant and three susceptible to the carmine cochineal. Treatments were arranged in a randomized complete block design and were replicated three times. Nutritional divergence was assessed using canonical variate analysis and hierarchical agglomerative clustering, using the variables: crude protein, total and non-fibrous carbohydrates, degradation rate and potential dry matter degradation. Five distinct nutritional groups were identified: Group I (OO), Group II (F-13 and F-15), Group III (OEA, OEM, COP, IPA 20 and GG), Group IV (V-16 and F-08) and Group V (Miuda, IS and F-21). Group II (F-13 and F-15; resistant genotypes) showed a chemical composition degradability in vitro suggesting it may have the greatest nutritive value as ruminant feed, while Group I had the least. Spineless cactus genotypes resistant to the carmine cochineal showed nutritional characteristics similar to or better than traditionally used cactus genotypes, such as Gigante and IPA 20, which can expand the range of options for using this forage. [ABSTRACT FROM AUTHOR]

Re-ensiling of previously ensiled forage has been a common practice in Brazil, and the use of inoculants may provide a means of reducing dry-matter ( DM) loss. This study aimed to determine the effect of re-ensiling and the use of microbial inoculants on the quality of sorghum silage. Treatments were presence/absence of an inoculant ( Lactobacillus plantarum and Propionibacterium acidipropionici) in the silage, and the re-ensiling, or not, of the material after 24 h of exposure to air, and these were tested in a factorial 2 × 2 design. Losses due to gas, effluent and total DM were assessed, as were the fermentation characteristics, chemical composition, aerobic stability, and aerobic counts of microorganisms. Effluent loss was higher in re-ensiled silage, and these silages had lower lactic acid content and higher levels of acetic and propionic acids. The in vitro DM digestibility was lower in the re-ensiled sorghum silages. The re-ensiled silage had higher aerobic stability. The inoculant only increased the acetic acid content of the silage. The re-ensiling of sorghum silage increased effluent loss by 71·2%, and reduced DM digestibility by 5·35%. The use of inoculant did not influence the quality of sorghum silage. [ABSTRACT FROM AUTHOR]

The present study aimed to evaluate two rotational stocking intervals (GI) over three consecutive grazing periods on forage productivity, crude protein and neutral detergent fibre of Urochloa brizantha cv. Marandu pastures, and the subsequent impact on milk production. Grazing treatments were (1) fixed rest period at 30 days (30-FG) and (2) grazing interval when canopy was intercepting 95% photosynthetically active radiation (95-LI). Eighteen multiparous Holstein × Zebu cows (548 ± 61.0 kg bodyweight, BW) and 70 ± 18.1 days in milk were used. Experiment lasted for 99 days (i.e. 33 days per period). Nine cows with similar milk production and BW were randomly allocated to each GI treatment balanced on milk production and BW. The adjustment of carrying capacity per paddock was made aiming to achieve a post-grazing residual height of 20 cm. For this, additional dry Holstein × Zebu cows (averaging 550 kg BW) were added and removed from the paddocks according put-and-take technique. Data were statistically analysed considering field sites as block (n = 2), GI (30-FG vs 95-LI), periods (three consecutive) and interaction GI × periods. Interactions occurred between GI and periods for pre- and post-grazing height (P ≤ 0.05). Greater pre-grazing height was observed for 30-FG (P < 0.01), but post-grazing height was greater (P < 0.01) for 30-FG only in the third period. GI for treatment 30-FG was ~6 days longer (P = 0.01) than that for 95-LIand light interception was greater (2%) for 30-FG. Total forage, stem and dead material mass per area were greater (P < 0.01) for 30-FG than 95-LI. However, stocking rate was 11.3% greater (P = 0.02) for 95-LI than 30-FG. In the pre-grazing period, 95-LI had greater (P < 0.01) proportion of leaves and a greater leaf : stem ratio, whereas neutral detergent fibre concentration tended to be lower (P = 0.08) and crude protein concentration greater (P < 0.01) in 95-LI than in 30-FG. Daily milk productivity per area and its components were 16-28% greater (P < 0.01) for 95-LI than for 30-FD. These results suggest that GI of Marandu grass determined by light interception at 95% (95-LI) enabled the reduction of GI, improved forage nutritive value and increased milk productivity compared with a fixed 30 days (30-FG) of rest. [ABSTRACT FROM AUTHOR]

Pearl millet (Pennisetum glaucum (L.) R.) could play an important role as a feed source for ruminants in arid and semi-arid zones of the world owing to its high yield and drought tolerance. The current paper assessed the agronomic characteristics, ensilability, intake and digestibility of five Brazilian pearl millet cultivars (IPA Bulk1BF, BRS 1501, CMS-03, CMS-01 and BN-2) in a typical Brazilian northeastern semi-arid climate. Forage was harvested at the dough stage of grain maturity (growth stage 86 according to the BBCH scale) and ensiled under laboratory and farm conditions. Apparent digestibility of the silages was determined using 25 Santa Inês male lambs. The cultivars CMS-01, CMS-03 and BN-2 out-performed the others in terms of dry matter (DM) and digestible DM yield/ha. At DM partitioning among plant tissues, the cultivar IPA Bulk1BF had a greater DM associated with panicles and one of the greatest concentrations of organic matter, lactic acid and in vitro dry matter digestibility among the five cultivars. The cultivar BRS 1501 had greater butyric acid concentration as well as one of the highest pH values. Silage produced from BN-2 not only contained greater acetic acid concentration, but also showed one of the greatest total volatile fatty acid concentrations. There were no differences in feed intake and digestibility of nutrients and fibre fractions across all cultivars. Silage made from BN-2 resulted in greater urinary excretion of nitrogen than those produced from BRS 1501. Under the conditions of the present study, the results obtained for production of DM and digestible dry matter, and the ratio of plant fractions, indicates the possible use of these cultivars for silage production in the Brazilian semi-arid region. [ABSTRACT FROM PUBLISHER]

In vitro batch cultures were used to screen four fibrolytic enzyme mixtures at two dosages added to a 60 : 40 silage : concentrate diet containing the C4 tropical grass Andropogon gayanus grass ensiled at two maturities – vegetative stage (VS) and flowering stage (FS). Based on these studies, one enzyme mixture was selected to treat the same diets and evaluate its impact on fermentation using an artificial rumen (Rusitec). In vitro batch cultures were conducted as a completely randomized design with two runs, four replicates per run and 12 treatments in a factorial arrangement (four enzyme mixtures×three doses). Enzyme additives (E1, E2, E3 and E4) were commercial products and contained a range of endoglucanase, exoglucanase and xylanase activities. Enzymes were added to the complete diet 2 h before incubation at 0, 2 and 4 μl/g of dry matter (DM). Gas production (GP) was measured after 3, 6, 12, 24 and 48 h of incubation. Disappearance of DM (DMD), NDF (NDFD) and ADF (ADFD) were determined after 24 and 48 h. For all four enzyme mixtures, a dosage effect (P<0.05) was observed for NDFD and ADFD after 24 h and for DMD, NDFD and ADFD after 48 h of incubation of the VS diet. For the FS diet, a dosage effect was observed for GP and NDFD after 24 h and for GP, DMD, NDFD and ADFD after 48 h of incubation. There was no difference among enzyme mixtures nor was there an enzyme×dose interaction for the studied parameters. Because of the greatest numerical effect on NDF disappearance and the least cost price, enzyme mixture E2 at 4 µl/g of diet DM was selected for the Rusitec experiment. The enzyme did not impact (P>0.05) DM, N, NDF or ADF disappearance after 48 h of incubation nor daily ammonia-N, volatile fatty acids or CH4 production. However, enzyme application increased (P<0.05) microbial N production in feed particle-associated (loosely-associated) and silage feed particle-bound (firmly associated) fractions. With A. gayanus silage diets, degradation may not be limited by microbial colonization, but rather by the ability of fibrolytic enzymes to degrade plant cell walls within this recalcitrant forage. [ABSTRACT FROM PUBLISHER]

The article discusses the study on the methane production and energy partitioning in sheep's who are fed silages of sorghum hybrids at different maturation stages.

The article discusses a study that forms an equation to calculate the volume of gases produced using the pressure data received from in vitro fermentation of substrate incubated in F57 bags. Highlights include chemical composition of forage samples from the whole plant and plant fractions of the sweet sorghum variety, a needle used for estimating the volume and pressure of the gases, and a diagram of the equipment used for measuring pressure and volume of the gases during in vitro fermentation.

The article discusses a study that examines and compares dry matter (DM), crude protein (CP), and neutral detergent fiber ruminal degradation kinetics of Andropogon gayanus grass silages harvested at three stages of maturity. Topics discussed include chemical composition of Andropogon gayanus grass silages harvested at three phases of maturity, equation used to estimate effective ruminal CP disappearance, and reduction of DM degradability with increasing regrowth age.

A comprehensive and detailed computational fluid dynamics (CFDs) modelling of air flow and heat transfer in an open refrigerated display cabinet (ORDC) is performed in this study. The physical-mathematical model considers the flow through the internal ducts, across fans and evaporator, and includes the thermal response of food products. The air humidity effect and thermal radiation heat transfer between surfaces are taken into account. Experimental tests were performed to characterize the phenomena near physical extremities and to validate the numerical predictions of air temperature, relative humidity, and velocity. Numerical and experimental results comparison reveals the predictive capabilities of the computational model for the optimized conception and development of this type of equipments. Numerical predictions are used to propose geometrical and functional parametric studies that improve thermal performance of the ORDC and consequently food safety. [ABSTRACT FROM AUTHOR]

A detailed CFD modelling of an open refrigerated display cabinet has been formulated in a previous study. Some modifications are introduced in order to perform parametric studies dealing with low-cost geometrical and functional characteristics for improvement of the global performance and energy efficiency. The parametric studies are devoted to the analysis of the thermal response and behaviour inside the food conservation space influenced by (1) air flow rate through the evaporator heat exchanger; (2) air curtain behaviour; (3) hole dimensions and distribution of the back panel; (4) discharge and return grilles angles; and (5) flow deflectors inside the internal duct. The analysis of the numerical predictions from the parametric studies allows the development of an optimized model for the conception of an open refrigerated display cabinet with a more adequate configuration. The numerical predictions of the optimized model show lower product temperature and reduced electrical energy consumption, allowing the improvement of the food safety and the energy rationalization of the refrigeration equipment. [ABSTRACT FROM AUTHOR]

The article reports on a study on the effects of sorghum BRS-610 grain silages as it reached maturity stage after 56 days of fermentation conducted at National Research Center of Corn and Sorghum, Minas Gerais, Brazil from 2005 to 2006. The study shows that the quality of fermentation and nutritional value is relative to grain maturity stage as it indicates that milky to dough and dough stages show good fermentation quality and nutritional value.

In this work the implementation of an optical fiber interferometric system for differential thermal analysis enabling the identification of chemical species is described. The system is based on a white light Mach-Zehnder configuration using pseudo-heterodyne demodulation to interrogate two identical fiber Bragg gratings (FBG) in a differential scheme. System performance is compared using either standard hardware or low cost virtual instrumentation for operation control and signal processing. The operation with the virtual system enabled temperature measurements with a ±0.023 °C resolution nearly matching the performance of the standard hardware. The system ability to discriminate chemical species by differential thermal analysis was demonstrated. Mixed samples of acetone and methanol could be successfully identified, indicating the suitability of the system for high precision measurements using low cost instrumentation. [ABSTRACT FROM AUTHOR]