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Palmeira das Missões, Brazil

Righi E.Z.,Federal University of Santa Maria | Heldwein A.B.,Federal University of Santa Maria | Maldaner I.C.,Instituto Federal Farroupilha | Lucas D.D.P.,Secretaria da Agricultura | Stuker P.E.,ABG Engineering e Meio Ambiente LTDA
Revista Ciencia Agronomica

New coefficients were determined for the weighting term for cloudiness in the Brunt-Penman equation using the rate of solar radiation (RK) in place of the rate of sunshine duration (n/N). The coefficients in the Brutsaert method proposed for daytime in southern Brazil were also tested and adjusted, and the method was selected which gave the more accurate daily results in relation to the original Brunt-Penman equation, for Santa Maria in the state of Rio Grande do Sul, Brazil (RS). Meteorological data covering 2,472 days obtained from the automatic and conventional weather stations in Santa Maria were used. The coefficients were adjusted by linear and nonlinear regression methods depending on the model, using 2/3 of the data. The adjusted equations were tested with the remaining 1/3 of the data. The Brunt-Penman equation modified by the term for cloudiness weighted both for solar radiation incident on the surface with no cloudiness (RK,R) and for solar radiation incident at the top of the atmosphere (RK,K), were those that resulted in the best statistical indices relative to the original Brunt-Penman equation. In those equations the boundary conditions, 0.3≤RK,R≤1 or RK,K≥0.22, were imposed. Although having similar statistical indices, a sensitivity analysis showed that the Brutsaert equation and other weightings for cloudiness resulted in larger deviations when compared to the original Brunt-Penman equation, in addition to having greater complexity for practical application. Source

Lucas D.D.P.,Secretaria da Agricultura | Heldwein A.B.,Federal University of Santa Maria | Hinnah F.D.,Escola Superior de Agronomia Luiz de Queiroz | Maldaner I.C.,Instituto Federal Farroupilha | Loose L.H.,Federal University of Santa Maria
Revista Ciencia Agronomica

The aim of this study was to obtain a mathematical model for estimating the leaf area index (LAI) of a sunflower crop as a function of accumulated thermal time. Generating the models and testing their coefficients was carried out using data obtained from experiments carried out for different sowing dates in the crop years of 2007/08, 2008/09, 2009/10 and 2010/11 with two sunflower hybrids, Aguará 03 and Hélio 358. Linear leaf dimensions were used for the non-destructive measurement of the leaf area, and thermal time was used to quantify the biological time. With the data for accumulated thermal time (TTa) and LAI known for any one day after emergence, mathematical models were generated for estimating the LAI. The following models were obtained, as they presented the best fit (lowest rootmean-square error, RMSE): gaussian peak, cubic polynomial, sigmoidal and an adjusted compound model, the modified sigmoidal. The modified sigmoidal model had the best fit to the generation data and the highest value for the coefficient of determination (R2). In testing the models, the lowest values for root-mean-square error, and the highest R2 between the observed and estimated values were obtained with the modified sigmoidal model. Source

Neto M.R.T.,Pos Graduacao em Zootecnia | da Cruz J.F.,UESB | Malhado C.H.M.,UESB | Carneiro P.L.S.,UESB | And 3 more authors.
Revista Brasileira de Zootecnia

The objective of this study was to characterize body biometrics of Santa Ines sheep during growth. Data from 4,038 animals, males and females, with ages from four to 36 months, from different herds participating in the National Agricultural Fair in Bahia from 2003 to 2008 were used. The characteristics evaluated were: body weight, average daily gain, body length, thoracic circumference, anterior height and posterior height. The mean values found were compared by the Student-Newman-Keuls test. All characteristics studied showed gradual change with aging, and it is worth-noting that age had positive effect on body weight, body length, thoracic circumference, anterior height and posterior height and negative effect on average daily gain. Average daily gain was reduced by 68.5% from four to 36 months of age, while the mean improvements observed in both sexes in this age range, for body weight, body length, thoracic circumference, anterior height and posterior height were 137.8%, 23.5%, 43.2%, 19.3% and 19.6%, respectively. However, the increments for body weight, body length and thoracic circumference were higher until 12 months of age, when an increase of 72.7%, 14.6% and 24.8% in their respective characteristics was verified. For anterior height and posterior height, the greatest increase occurred up to eight months of age with improvement of 8.4% for both measures. Santa Ines sheep have different growth rates for body measurements; whereas growth in posterior height stabilizes earlier, the thoracic circumference, along with body weight, remains growing for longer time. © 2012 Sociedade Brasileira de Zootecnia. Source

Raymundo D.L.,Federal University of Lavras | Gomes D.C.,Federal University of Rio Grande do Sul | Boabaid F.M.,Federal University of Rio Grande do Sul | Colodel E.M.,Federal University of Mato Grosso | And 4 more authors.
Pesquisa Veterinaria Brasileira

The p aper addresses the epidemiologic data of the death of pigs during the period of 2002 to 2009 following the ingestion of botulinum neurotoxin type C. This neurotoxin was present in food residues originating from restaurant and hotel kitchens, stored in barrels without shelter from the sun and administered in a collective trough without prior thermal treatment. Animals which died at different ages showed clinical signs of botulism characterized by flaccid paralysis, weight loss, anorexia, weakness, lack of coordination, locomotion difficulties with the evolution of lateral recum bency with involuntary urination and defecation. No alterations were observed at postmortem and histological examination. The bioassay with serum neutralization in mice was carried out on samples of intestinal contents from pigs affected and revealed the presence of large quantities of botulinum toxin type C. Source

De Sousa e Silva G.,Federal University of Rio Grande do Sul | Costa E.,Federal University of Rio Grande do Sul | Bernardo F.A.,Companhia de Processamento de Dados do Rio Grande do Sul | Groff F.H.S.,Secretaria da Agricultura | And 3 more authors.
Acta Scientiae Veterinariae

Background: The economy of Rio Grande do Sul (RS) relies majorly on agriculture; among the livestock production chains, cattle production has the largest economic, historical, and cultural importance in RS. The cattle industry is the main zootechnical activity in RS. Due to this, there is an actual need for updated characterization of the animal population, considering the population dynamics and the requirements imposed by the Official Veterinary Service (SVO) to meet certain characteristics. This would facilitate appropriate policies and measures to safeguard the health of the cattle in RS, as well as safeguard public health, and consequently avoid the economic impacts of possible health events. Materials, Methods & Results: Based on data from the livestock survey of 2013 from the Department of Animal Health (DDA), the Secretariat of Agriculture, Livestock, and Agribusiness of the State of Rio Grande do Sul (SEAPA-RS), descriptive and spatial analyses of the cattle population were performed using software R and ArcMap TM 10, respectively. It was observed that the state has more than 13 million cattle distributed over approximately 346,000 farms. The majority of the bovine population consists of females over the age of 36 months. The predominant function of these farms is a complete cycle (breeding to fattening). Beef production is the predominant activity, followed by a mix of beef production and dairy production, and then sole dairy production. These characteristics differ depending on the state's region. Regarding the number of animals per property, 88% of properties are small having up to 50 cattle, and about 1% of properties have more than 500 animals. The general average in the state for the proportion of T:V (calf: cow) is 57 calves per 100 cows, and this is close to the national average. Discussion: About 60.62% of cattle herds consisted of animals aged over 24 months, and most of this group were females over 36 months of age (38.95%). About 50% of properties have up to 10 animals, demonstrating a large proportion of small farms. RS has an imbalance in its production system, with a large number of breeding females for the activity of beef production. The cattle in RS are mostly bred for the production of beef in a full cycle system (with all stages of production on the property), and only 10% of cattle raised in RS are bred solely for milk production. With regard to the proportion of T:V, we concluded that the state's beef production shows modest productivity and needs to improve production rates to increase financial returns for producers and enable competitiveness in the domestic and international markets. Furthermore, this information correlates with previous studies that have reported that farms in the business of beef production use low technology and low performance animals. Dairy farming, in contrast with beef farming, has been modernizing and developing in recent years by increasing co-operatives and agribusinesses, which has led to greater knowledge through technical assistance to the farms. Extensive farming is dependent on field areas and is historically associated with the natural fields in the campaign region, since dairy farming is dependent on areas where there is a supply of specialized food. Thus, despite the state having a greater concentration of animals in the south-southwest, production indices are similar to other regions, and the type of farming undertaken exerts a great influence on the regional animal population structure. Source

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