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Magalhaes F.A.,Federal University of Viçosa | Valadares Filho S.C.,Federal University of Viçosa | Menezes G.C.C.,Federal University of Viçosa | Machado M.G.,Federal University of Viçosa | And 4 more authors.
Revista Brasileira de Zootecnia | Year: 2012

The objective of this study was to evaluate the effect of sugar cane ensilage with different Brix degrees, with or without the addition of 0.5% of calcium oxide (lime) on the chemical composition and fermentation losses of silages. A complete random design in a 9 × 2 factorial arrangement was used. Experimental silos were used, ensilage was done every 15 days with Brix measuring, and they were opened after 30 days of fermentation. As the Brix degree of the ensiled material increased, the contents of dry matter (DM) increased and contents of ash, crude protein (CP) and fibers (neutral and acid detergent fiber corrected for proteins - NDFap and ADFap) reduced. After fermentation, DM content of the silage presented a linear increase with the Brix degree content concentration, positively correlating with content of lime, but the contents of ash, CP, EE and NDFap were linearly reduced with the Brix increase. Content of ADFap suffered linear reduction for the treated silage whereas quadratic behavior was found in the untreated silage. Production of ethanol was presented in a quadratic manner for the silages without lime, and cubically in silages with lime, according to the Brix degree. The treated or untreated silages presented an average pH of 3.98 and 3.50, respectively. Contents of acetic acid and butyric acid were not affected by the lime content and Brix degree. Untreated silages presented reduction of contents of propionic acid as the Brix degree increased. The higher the Brix degree value, the higher the total losses of dry matter in the sugar cane silages with or without treatment. The treatment of the sugar cane with 0.5% calcium oxide on the natural matter basis is effective in reducing the undesired fermentation of the ensilage material. © 2012 Sociedade Brasileira de Zootecnia.

Nogueira R.M.,Institute Ciencias Agrarias e Ambientais | Alvares V.S.,EMBRAPA - Empresa Brasileira de Pesquisa Agropecuária | Ruffato S.,Institute Ciencias Agrarias e Ambientais | Lopes R.P.,Federal University of Viçosa | Silva J.S.E.,Federal University of Viçosa
Engenharia Agricola | Year: 2014

The Brazil-nut, also known as Para-nut, is widely used as food and in cosmetic industries. The seeds are rich in lipids and protein, and also present a considerable amount of selenium. Limited research has been conducted on postharvest of the Brazil nut, being an important information to design equipment related to aeration, drying, storage and transportation steps. Thus, the objective of this study was to determine the physical properties of the Brazil-nut with and without tegument. The dimensions found for the almonds with tegument were 39.35 mm in the X axis, 24.19 mm in the Y axis, and 17.88 mm in the Z axis. However for the almond without tegument the values were 31.05 mm in X, 14.38 in Y and 15.91 mm in Z axis. The sphericity was 66.40% and 51.59% for the kernels with and without seed tegument respectively. The kernels with and without tegument presented sphericity of 63.00% and 47.72% respectively. The mass of 1000 almonds was 6.13 kg for almond with teguments and 3.18 kg for almonds without teguments. Specific mass of 0.947 g.cm-3 and 1.003 g.cm-3 for the kernels with and without tegument, coupled with a porosity of 46.88% and 37.60% and, resulting on a bulk density of 0.504 g.cm-3 and 0.626 g.cm-3 for almonds with and without teguments respectively. Finally, the angle of repose for the kernels with teguments was 36.37°.

Magalhaes F.A.,Federal University of Viçosa | Filho S.D.C.V.,Federal University of Viçosa | Menezes G.C.D.C.,Federal University of Viçosa | Gionbelli M.P.,Federal University of Viçosa | And 4 more authors.
Revista Brasileira de Zootecnia | Year: 2012

The objective of this study was to evaluate low and high Brix diets, treated or not with 5 g of calcium oxide per kg of natural matter, and corn silage on intake, digestibility and performance of beef cattle. Forty cattle with initial body weight (BW) of 350 kg were used: five composed the control group, 30 were distributed into random blocks (control) and the other five were distributed in a 5 × 5 incomplete Latin square, with the objective of determining digestibility. The 30 animals evaluated for performance were slaughtered and empty body weight (EPW), carcass dressing and meat cuts were determined. The diet with corn silage (CS) presented the best intake of the other ingredients and the best weight gain, except for neutral detergent fiber intake in g/kg of BW. Only carcass dressing, in relation to BW and EBW, was not affected by the treatments, and the others were greater for animals fed diets with sugar cane silage. Animals fed diets with high brix sugar cane silage and treated high brix sugar cane silage presented lower intake of indigestible neutral detergent fiber and neutral detergent fiber corrected for ash and protein (g/kg of BW) in relation to diets with low and high brix sugar cane silage, respectively. Animals fed diets with corn silage presented higher digestibility, except for crude protein and non-fibrous carbohydrates. Animals subjected to diets with corn silage presented low excretion of nitrogen compounds and higher microbial crude protein synthesis. Animals fed sugar cane silage present greater intake, performance and digestibility. The use of lime during 15 or 20° Brix sugar cane ensilage does not alter intake, digestibility or performance of beef cattle. © 2012 Sociedade Brasileira de Zootecnia.

Pereira D.R.,Institute Ciencias Agrarias | Uliana E.M.,Institute Ciencias Agrarias e Ambientais | Martinez M.A.,Federal University of Viçosa | da Silva D.D.,Federal University of Viçosa
IRRIGA | Year: 2016

Hydrological models are important tools which have been used in the planning and management of water resources, reason why the aim of the study was to calibrate, validate and analyze IPH II and SWAT models’ performances to simulate theaverage daily flow rates of a sub-basin of Pomba river, located in Minas Gerais State, Brazil. Rainfall data and reference evapotranspiration were used for the simulation with the IPH II model. On the other hand, for the simulation with SWAT, spatial data were used (soil maps, land use and topography) and discrete data (rainfall, maximum and minimum temperature, radiation, relative humidity, wind speed, vegetation, groundwater and physical-hydric characteristics of soils). Calibration was performed by the automatic method based on Nash-Sutcliffe coefficient. Validation and verification of the models’ performance were based on the mean absolute error, root mean squared error, in bias, pared t-test at 5% probability, Willmott concordance and Nash-Sutcliffe efficiency index. The IPH II and SWAT models showed good and satisfactory results in estimating average daily flow rates based on the Nash- Sutcliffe coefficient, respectively, however, the SWAT showed values statistically different from those observed in the validation period at 5% probability by pared t-test, which shows that the IPH II model is more reliable and suitable for use in studies related to hydrologic simulation and management of water resources in the watershed. © 2016, Universidade Estadual Paulista - UNESP. All rights reserved.

de Carvalho D.F.,Vegetal | da Silva D.G.,Institute Ciencias Agrarias e Ambientais | de Souza A.P.,FRRJ | Gomes D.P.,Federal Rural University of Rio de Janeiro | da Rocha H.S.,Federal Rural University of Rio de Janeiro
Revista Brasileira de Engenharia Agricola e Ambiental | Year: 2011

The reference evapotranspiration (ETo) is dependent on the amount of energy available in the environment, being solar radiation (SR) as an important variable in its estimation. This study was carried out in order to determine the coefficients "a" and "b" of the Angstron-Prescott equation for Seropédica, Rio de Janeiro State, Brazil, and to evaluate their effects on the SR and ETo estimation. Measures of global solar radiation and effective number of hours of sunshine were used from station Ecology Fund (83741 - INMET) for the period of 2000 to 2007. The coefficients were determined by linear regression analysis for the entire period and monthly and yearly periods. Using the calculated coefficients and those proposed by FAO (0.25 and 0.50) SR and ETo were estimated and evaluated their performance. The average monthly coefficients "a" ranged from 0.232 to 0.299 and "b" from 0.397 to 0.504. Annual mean coefficients "a" and "b" were 0.295 and 0.417, and for general period were 0.282 and 0.433, respectively. The best performance observed for the estimated SR and ETo was obtained when the monthly coefficients of the equation Angströn-Prescott were adopted.

Neto M.C.,SEBRAE | Campos J.M.S.,University of Pernambuco | de Oliveira A.S.,Institute Ciencias Agrarias e Ambientais | Gomes S.T.,Vicosa MG
Revista Brasileira de Zootecnia | Year: 2012

The objective of this study was to identify and quantify benchmarks of milk production systems. The technological profile and size, livestock and economic indicators of sixteen farms in the region of Triângulo Mineiro were analyzed. Indicators correlated with rate of return on capital (RRC) were identified and quantified in four scenarios of RRC (6, 8, 10 and 12% per year). The correlated indicators and their respective values in the four scenarios were: land (99, 90, 81 and 73 ha); relation of total cows in lactation (74, 77, 79 and 82%); lactating cows per area (0.89; 0.99; 1.11 and 1.22 cows/ha); milk production per lactating cow (12.04; 13.00; 13.96 and 14.92 liters/cow/day); milk production per total cows (9.19; 10.23; 11.27 and 12.31 liters/cow/day); labor productivity (322, 349, 375 and 402 liters/day/man); land productivity (4351, 5236, 6120 and 7004 liters/ha/year); participation of total effective operational cost of activity in the gross revenue of the activity (69, 66, 63 and 60%); participation of total operational cost of activity in the gross revenue of the activity (80, 76, 72 and 69%); participation of total cost of activity in the gross revenue of the activity (93, 88, 82 and 77%); labor cost in relation to milk gross revenue (15, 13, 11 and 9%); profitability (15, 19, 23 and 28%); and capital investment in the activity in relation to daily milk production (922, 829, 736 and 644 R$/liter-day). The productivity of the factors land and animals present more correlation with profitability than labor productivity, regardless of the production size. ©2012 Sociedade Brasileira de Zootecnia.

da Silva A.C.,Institute Ciencias Agrarias e Ambientais | da Souza A.P.,Institute Ciencias Agrarias e Ambientais | Ducatti C.,São Paulo State University | Leonel S.,São Paulo State University
Revista Brasileira de Fruticultura | Year: 2011

The aim of this study was to assess carbon-13 turnover in different organs of the fig tree cultivar 'Roxo de Valinhos'. The experiment was carried out in an orchard at School of Agronomical Sciences, FCA/UNESP, Botucatu Campus, São Paulo State, Brazil. The main photosynthetically active leaf was previously determined based on gas exchanges by means of an open portable photosynthesis system, IRGA. That leaf was placed in a chamber where the enriched gas injection occurred. The leaf enrichment time was 30 minutes. Treatments were constituted of seven fig trees harvested of soil after: 6; 24; 48; 72; 120; 168 and 360 hours of enrichment using 13C, and their parts were sectioned into: apical bud, young leaves, adult leaves (photosynthetically active), lateral sprouts, fruits, and branch. The results allowed the establishment of the carbon-13 metabolism sequence in the studied parts: Young leaves > Fruits > Sprouts > Adult leaves > Apical bud > branch > Labeled leaf. Fig trees 'Roxo de Valinhos' had 13C turnover of 24 hours and carbon-13 half-time shorter than 11 hours.

Souza A.P.,Institute Ciencias Agrarias e Ambientais | Escobedo J.F.,São Paulo State University | Pai A.D.,Av. Jose Italo Bacchi s n | Gomes E.N.,São Paulo State University
Revista Brasileira de Engenharia Agricola e Ambiental | Year: 2011

Statistics equations and validations with groups of annual and monthly data were evaluated for global, direct and diffuse solar radiation components incident on the tilted surface to 12.85, 22.85 and 32.85° with the face North, in climate and geographical conditions of Botucatu, SP. It was employed the fractions of three components of extraterrestrial radiation in correlation with the coefficient clearness index horizontal plane, in a database of April/1998 to December/2007, whose measures at different periods in three inclinations, however concomitant to the horizontal plane. Increasing the angle of the surface led to increased scattering of the daily values of clearness index for inclined and horizontal surfaces. In annual groups, the lower performances were observed in the estimation of inclined daily diffuse radiation, with maximum Root Mean Square Error to 3.89 MJ m -2 d -1 (43.65%) and adjustments around 62%. In estimates of global and direct components of solar radiation on inclined planes, both annual and monthly equtions can be applied, with performance dependents to climatic conditions.

Gomes H.F.B.,Institute Ciencias Agrarias e Ambientais | de Menezes J.J.L.,São Paulo State University | Goncalves H.C.,São Paulo State University | Canizares G.I.L.,São Paulo State University | And 4 more authors.
Revista Brasileira de Zootecnia | Year: 2011

This study was carried out with the objective of evaluating the influence of breed groups and sexual conditional on carcass traits of young goats raised in feedlot. It was used 91 animals, 52 males and 39 females, belonging to five breed groups: Alpine, 1/2Boer + 1/2Alpine, 1/2Nubian + 1/2Alpine, 3/4-Boer + 1/4Alpine and 1/2 Anglo-Nubian + 1/4Boer + 1/4Alpine. On the slaughter day, the shrunk weight was measured after 24 hours of solid fasting. Biometric and carcass measures were objectively and subjectively taken. Racial group influenced withers, internal and external carcass length, and leg length, which were greater for Alpine animals, as well as chest width, body condition score, carcass and leg compactness index and fat thickness on carcass, which were better in animals with Boer blood degree. Male animals showed greater withers, measures of sternebrae by ultrasound, internal carcass length, leg length, tissue depth height between 3rd and 4th sternebrae measured on carcass. On the other body evaluated characteristics, it was not found any differences among breed groups and sex of the animals. Crossing Boer with Alpine reduces carcass length, and increases fat thickness and deposited tissue, however, it does not change animal performance. © 2011 Sociedade Brasileira de Zootecnia.

Machado T.M.,Institute Ciencias Agrarias e Ambientais | Lancas K.P.,São Paulo State University | De Oliveira Junior M.B.,Trelleborg Santana do Parnaiba SP | Artioli J.A.,Trelleborg Santana do Parnaiba SP | Marasca I.,São Paulo State University
Engenharia Agricola | Year: 2015

The power consumption and load capacity of agricultural machines have grown and the effects of pressure on the soil by tires have been still little investigated. In concern with sustainable development, the relationship machine-tire-soil must be in balance to give more consistency on the best use of tires for a given load. This study aimed to evaluate four tires of two constructive types, the bias belted tires and radial tires, both with respective rim diameters of 22.5 and 26.5 inches with variables measuring the footprint, elastic deformation, sinkage and resistance to penetration. A hydraulic press with an attachment shaft for tire mounting and a box of soil in which the tire has been imposed on a load of 53.00 kN using nominal pressures recommended by the tire manufacturer. The radial construction tire with rim diameter of 26.5 inches obtained less sinkage and resistance to penetration; however, greater elastic deformation and footprint compared to other tires. The bias-belted tire with 22.5-inch rim presented the highest resistance to penetration and the lowest elastic deformation.

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