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In this research, the Volumetric Median Diameters (VMDs), Relative Span (RS), percentage of droplets with a diameter smaller than 100 µm (V100), and percentage ofdrift (% drift) of four droplet classes (Fine, Medium, Coarse, and Very Coarse) were analyzedin two spray volumes (77 L.ha-1and 144 L.ha-1) employinga tank-mix of atrazine and nicosulfuron herbicides (2500 + 15 gaiha-1), usingParticle/Droplet Imaging Analyze (PDIA) and wind tunnel techniques. The experiments were performed under Completely Randomized Design, in a 4 × 2 factorial scheme (droplet classes × sprayvolumes). Data underwent analysis of variance and Tukey's test at 5%, and the correlation between variables was computedconsidering Pearson's coefficient at 1% and 5%. The VMD of all droplet classes was considerably distinct in the two spray volumes. In both application spray volumes, the minimum VMD for the Coarsedropletclass classification was not attained. The highest means of RS were detectedin the spray volume of 77 L.ha-1. All treatments demonstratedsignificant differences in the analysis of V100 and % drift, with the highest means observed in the Fine droplet (144 L.ha-1) and Medium (77 L.ha-1). A negative correlation existed between VMD × V100 and VMD × % drift and a positive correlation between V100 × % drift in the two spray volumes. RS was negatively correlated with VMD and positively with V100 and % drift, in the spray volume of 77 L.ha-1. In the spray volume of 144 L.ha-1, the correlation between RSand VMD, V100, and % drift was insignificant.

Nesta pesquisa foram avaliados os Diâmetros Medianos Volumétricos (DMVs), Amplitude Relativa (AR), percentual de gotas com diâmetro menor que 100 µm (V100) e porcentagem de deriva (% deriva) de quatro classes de gota (Fina, Média, Grossa e Muito Grossa) em dois volumes de aplicação (77L.ha-1e 144L.ha-1) utilizando a mistura dos herbicidas atrazine e nicosulfuron (2500 + 15 gi.a. ha-1), utilizando os métodos de PDIA e de túnel de vento. Os experimentos foram realizados sob o delineamento inteiramente casualizado, no esquema fatorial 4 × 2 (classes de gota × volumes de aplicação), com cinco repetições. Os dados foram submetidos à análise de variância e ao teste de Tukey a 5%, e a correlação entre as variáveis calculada considerando o coeficiente de Pearson a 1% e 5%. O DMV de todas as classes de gotas foi significativamente diferente nos dois volumes. O DMV mínimo para a classificação da classe de gota Grossa não foi atingido nos dois volumes de aplicação. As maiores médias de AR foram observadas no volume de 77 L.ha-1. Todos os tratamentos apresentaram diferenças significativas na análise de V100 e % deriva com as maiores médias observadas nas classes de gota Fina (144 L.ha-1) e Média (77 L.ha-1). Verificou-se correlação negativa entre DMV × V100 e DMV × % deriva e correlação positiva entreV100 × % deriva nos dois volumes. No volume de 77 L.ha-1 a AR correlacionou-se negativamente com o DMV e positivamente com V100 e % deriva. No volume de 144 L.ha-1 a correlação entre AR e DMV, V100 e % deriva não foi significativa.

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The identification of promising commercial varieties for irrigated crops in semiarid conditions based on characters of interest to sugarcane agro-industries is important, considering the search for high sugarcane yields to obtain sustainable crops. Thus, the objective of this work was to evaluate production components of agroindustrial interest of different sugarcane varieties grown under subsurface drip irrigation in the Semiarid region of Brazil, during two crop cycles. A randomized block experimental design was used, in an 8×2 factorial arrangement (varieties and cycles) with three replications. The sugarcane juice quality, sugar yield, and culm yield were evaluated in each cycle. Gross sugar percentage, sugarcane culm yield, juice apparent sucrose content, and juice purity were affected by the crop cycles. Soluble solids content presented strong significant correlation with most variables of agroindustrial interest. The path coefficient analysis showed that juice apparent sucrose content was the explanatory character with higher direct effect on soluble solids and that this variable presented high indirect effects on most explanatory variables. The sugarcane varieties RB72454 and Q124 are recommended for production managements with drip irrigation under semiarid conditions. Soluble solids content can be used as an alternative for direct selection of varieties with higher sugar yields in different cycles.(AU)

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Several studies have reported the relationship of deforestation with increased incidence of infectious diseases, mainly due to the deregulation caused in these environments. The purpose of this study was to answer the following questions: a) is increased loss of vegetation related to dengue cases in the Brazilian Cerrado? b) how do different regions of the tropical savanna biome present distinct patterns for total dengue cases and vegetation loss? c) what is the projection of a future scenario of deforestation and an increased number of dengue cases in 2030? Thus, this study aimed to assess the relationship between loss of native vegetation in the Cerrado and dengue infection. In this paper, we quantify the entire deforested area and dengue infection cases from 2001 to 2019. For data analyses, we used Poisson generalized linear model, descriptive statistics, cluster analysis, non-parametric statistics, and autoregressive integrated moving average (ARIMA) models to predict loss of vegetation and fever dengue cases for the next decade. Cluster analysis revealed the formation of four clusters among the states. Our results showed significant increases in loss of native vegetation in all states, with the exception of Piauí. As for dengue cases, there were increases in the states of Minas Gerais, São Paulo, and Mato Grosso. Based on projections for 2030, Minas Gerais will register about 4,000 dengue cases per 100,000 inhabitants, São Paulo 750 dengue cases per 100,000 inhabitants, and Mato Grosso 500 dengue cases per 100,000 inhabitants. To reduce these projections, Brazil will need to control deforestation and implement public health, environmental and social policies, requiring a joint effort from all spheres of society.

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The drift of the herbicide glyphosate, used for desiccating crops or controlling weeds, can result in growth promoting or non-target plant development effects. Thus, it is possible to use the compound to increase the biomass of forage through the hormone effect. The objective of this study was to evaluate the effects of sublethal doses of glyphosate on the production of Urochloa brizantha cv. Marandu (Marandu grass) and its nutritional quality in ruminants. The design used was completely randomized, with five replications in a factorial scheme. The treatments used were as follows: control (without glyphosate application) and four sublethal doses of glyphosate (4, 10, 14, and 20 g ha-¹ of the acid equivalent). The monthly collections consisted of collecting the plant material (0.20 m) from the surface, comprising of leaves and pseudocolmos (stem and leaf sheath) to determine the dry matter production and forage chemical-bromatological parameters. The results showed that leaf/stem ratio, neutral detergent fiber, and acid detergent fiber were affected exclusively by the harvest factor. The hormone effect of the herbicide occurs in the production of dry matter and lignin in the evaluated subdoses. For crude protein, there was an interaction between the factor doses and harvest, due to the effect of glyphosate and the management applied to the harvests, showing that the sublethal doses of glyphosate promoted the production of dry matter and the food quality of Marandu grass.(AU)

A deriva do herbicida glifosato, usado para dessecação de culturas ou no controle de plantas daninhas, pode resultar em efeitos promotores de crescimento ou desenvolvimento de plantas não alvo. Assim, surge a possibilidade de utilização do composto para incremento da biomassa de forrageiras, por efeito hormese. O objetivo deste trabalho foi avaliar os efeitos da aplicação de doses subletais de glifosato na produção de Urochloa brizantha cv. Marandu (capim Marandu) e sobre a qualidade nutricional para ruminantes. O delineamento utilizado foi o inteiramente casualizado com cinco repetições, em esquema fatorial. Os tratamentos utilizados foram: controle (sem aplicação de glifosato) e quatro doses subletais de glifosato (4, 10, 14 e 20 g ha-¹ do equivalente ácido). As coletas mensais consistiram do recolhimento do material vegetal a 0,20 m da superfície, compreendendo folhas e pseudocolmos (colmo e bainha foliar) para determinação da produção de matéria seca e de parâmetros químico-bromatológicos da forragem. Os resultados mostraram que relação folha/colmo, fibra em detergente neutro e fibra em detergente ácido sofreram efeitos exclusivamente do fator corte. O efeito hormese do herbicida ocorre na produção de matéria seca e lignina nas subdoses avaliadas. Para proteína bruta houve interação entre os fatores doses e cortes, por efeito do glifosato e do manejo aplicado nos cortes, mostrando que as doses subletais do glifosato promovem a produção de matéria seca e a qualidade alimentar do capim Marandu.(AU)

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In this study, the stimulatory effects of application of glyphosate herbicide coupled with manganese sulfate (8%) foliar fertilizer on the production and bromatological characteristics of Brachiaria brizantha‘Marandu’ were evaluated. The experiments were performed using randomized complete block design with a 5×4 factorial scheme in plots subdivided over time (across four evaluations) with four repetitions, totaling 100 observations. The effects of sublethal doses of acid equivalent (a.e.) of glyphosate (5.40, 21.60, 64.80, and 108.00 g·a.e.·ha-1) and control plus manganese sulfate foliar fertilizer (1,000 g ha-1) were assessed in four successive evaluations at a defoliation frequency of 21 days. Foliage at 20 cm height (to evaluate forage production); leaf/stem ratio (LSR); and contents of crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), and lignin (LIG) were measured in experimental plots with a usable area of 7.5 m2. Application of sublethal doses of glyphosate plus manganese sulfate did not increase forage production, increased LSR, reduced LIG content, and did not affect CP content in all four evaluations. NFD and ADF indicated satisfactory qualitative indices for animal feed following the application of sublethal doses of glyphosate plus manganese sulfate in all four evaluations.

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In this study, the stimulatory effects of application of glyphosate herbicide coupled with manganese sulfate (8%) foliar fertilizer on the production and bromatological characteristics of Brachiaria brizantha‘Marandu were evaluated. The experiments were performed using randomized complete block design with a 5×4 factorial scheme in plots subdivided over time (across four evaluations) with four repetitions, totaling 100 observations. The effects of sublethal doses of acid equivalent (a.e.) of glyphosate (5.40, 21.60, 64.80, and 108.00 g·a.e.·ha-1) and control plus manganese sulfate foliar fertilizer (1,000 g ha-1) were assessed in four successive evaluations at a defoliation frequency of 21 days. Foliage at 20 cm height (to evaluate forage production); leaf/stem ratio (LSR); and contents of crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), and lignin (LIG) were measured in experimental plots with a usable area of 7.5 m2. Application of sublethal doses of glyphosate plus manganese sulfate did not increase forage production, increased LSR, reduced LIG content, and did not affect CP content in all four evaluations. NFD and ADF indicated satisfactory qualitative indices for animal feed following the application of sublethal doses of glyphosate plus manganese sulfate in all four evaluations.(AU)

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The drift of the herbicide glyphosate, used for desiccating crops or controlling weeds, can result in growth promoting or non-target plant development effects. Thus, it is possible to use the compound to increase the biomass of forage through the hormone effect. The objective of this study was to evaluate the effects of sublethal doses of glyphosate on the production of Urochloa brizantha cv. Marandu (Marandu grass) and its nutritional quality in ruminants. The design used was completely randomized, with five replications in a factorial scheme. The treatments used were as follows: control (without glyphosate application) and four sublethal doses of glyphosate (4, 10, 14, and 20 g ha-¹ of the acid equivalent). The monthly collections consisted of collecting the plant material (0.20 m) from the surface, comprising of leaves and pseudocolmos (stem and leaf sheath) to determine the dry matter production and forage chemical-bromatological parameters. The results showed that leaf/stem ratio, neutral detergent fiber, and acid detergent fiber were affected exclusively by the harvest factor. The hormone effect of the herbicide occurs in the production of dry matter and lignin in the evaluated subdoses. For crude protein, there was an interaction between the factor doses and harvest, due to the effect of glyphosate and the management applied to the harvests, showing that the sublethal doses of glyphosate promoted the production of dry matter and the food quality of Marandu grass.

A deriva do herbicida glifosato, usado para dessecação de culturas ou no controle de plantas daninhas, pode resultar em efeitos promotores de crescimento ou desenvolvimento de plantas não alvo. Assim, surge a possibilidade de utilização do composto para incremento da biomassa de forrageiras, por efeito hormese. O objetivo deste trabalho foi avaliar os efeitos da aplicação de doses subletais de glifosato na produção de Urochloa brizantha cv. Marandu (capim Marandu) e sobre a qualidade nutricional para ruminantes. O delineamento utilizado foi o inteiramente casualizado com cinco repetições, em esquema fatorial. Os tratamentos utilizados foram: controle (sem aplicação de glifosato) e quatro doses subletais de glifosato (4, 10, 14 e 20 g ha-¹ do equivalente ácido). As coletas mensais consistiram do recolhimento do material vegetal a 0,20 m da superfície, compreendendo folhas e pseudocolmos (colmo e bainha foliar) para determinação da produção de matéria seca e de parâmetros químico-bromatológicos da forragem. Os resultados mostraram que relação folha/colmo, fibra em detergente neutro e fibra em detergente ácido sofreram efeitos exclusivamente do fator corte. O efeito hormese do herbicida ocorre na produção de matéria seca e lignina nas subdoses avaliadas. Para proteína bruta houve interação entre os fatores doses e cortes, por efeito do glifosato e do manejo aplicado nos cortes, mostrando que as doses subletais do glifosato promovem a produção de matéria seca e a qualidade alimentar do capim Marandu.

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INTRODUCTION: We sought to determine risk factors (RFs) associated with the presence of antibodies against Leishmania in dogs from a rural area of Ilha Solteira, SP, Brazil. METHODS: Serum samples were collected from 250 dogs and tested using indirect enzyme-linked immunosorbent assay (ELISA) and indirect immunofluorescence antibody tests (IFATs). Data concerning dogs, their environment, and their owners' knowledge of leishmaniasis were collected using a questionnaire. To determine RFs for contact with the parasite, univariate statistical analysis based on chi-squared and Fisher's exact tests, followed by logistic regression, was used. RESULTS: It was found that 79/250 (31.6%) of the dogs were positive by IFAT, and 72/250 (28.8%) by ELISA. A total of 82/250 dogs (32.8%) were positive in at least one test. The RFs associated with occurrences of Leishmania exposure were large body size (OR = 2.25; 95% CI = 1.26-4.04; p = 0.003), presence of chickens (OR = 1.94; 95% CI = 1.05-3.65; p = 0.023), and lack of knowledge about Leishmania among dog owners (OR = 1.74; 95% CI = 0.96-3.21; p = 0.049). After multivariate analysis, the RFs for occurrence of Leishmania exposure in dogs that remained significantly associated were the dog's size (large dogs) (OR = 1.2; 95% CI = 1.06-1.35; p = 0.003) and presence of chickens on the properties (small farms) (OR = 1.15; 95% CI = 1.02-1.30; p = 0.023). CONCLUSIONS: These results may be useful for improving preventive practices to reduce the incidence of Leishmania exposure among dogs in rural areas.

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Abstract INTRODUCTION: We sought to determine risk factors (RFs) associated with the presence of antibodies against Leishmania in dogs from a rural area of Ilha Solteira, SP, Brazil. METHODS: Serum samples were collected from 250 dogs and tested using indirect enzyme-linked immunosorbent assay (ELISA) and indirect immunofluorescence antibody tests (IFATs). Data concerning dogs, their environment, and their owners' knowledge of leishmaniasis were collected using a questionnaire. To determine RFs for contact with the parasite, univariate statistical analysis based on chi-squared and Fisher's exact tests, followed by logistic regression, was used. RESULTS: It was found that 79/250 (31.6%) of the dogs were positive by IFAT, and 72/250 (28.8%) by ELISA. A total of 82/250 dogs (32.8%) were positive in at least one test. The RFs associated with occurrences of Leishmania exposure were large body size (OR = 2.25; 95% CI = 1.26-4.04; p = 0.003), presence of chickens (OR = 1.94; 95% CI = 1.05-3.65; p = 0.023), and lack of knowledge about Leishmania among dog owners (OR = 1.74; 95% CI = 0.96-3.21; p = 0.049). After multivariate analysis, the RFs for occurrence of Leishmania exposure in dogs that remained significantly associated were the dog's size (large dogs) (OR = 1.2; 95% CI = 1.06-1.35; p = 0.003) and presence of chickens on the properties (small farms) (OR = 1.15; 95% CI = 1.02-1.30; p = 0.023). CONCLUSIONS: These results may be useful for improving preventive practices to reduce the incidence of Leishmania exposure among dogs in rural areas.

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The objective of this study was to verify the presence of antimicrobial resistant strains of Escherichia coli in pig farms and to use it as a biomarker to evaluate phenotypic and genotypic profiles of antimicrobial susceptibility, as well as the presence of Extended Spectrum Beta-lactamases (ESBLs) and fluoroquinolone resistance genes. Several samples (n = 306) collected from swine farms (n = 100) of Southern Brazil were used for E. coli isolation: 103 of swine feces, 105 of water, and 98 of soil. E. coli isolates were submitted to the disk-diffusion test to verify their antimicrobial susceptibility, to disk-approximation test to detect ESBL-producers, and to PCR analysis to search for ESBLs genes (blaCTY-M2, blaSHV-1, blaTEM-1, blaCTX-M2, blaOXA-1, blaPSE-1) and quinolone resistance genes (qnrA, qnrB and qnrS). The percentage of E. coli isolates found in feces, water and soil samples was 66.02%, 30.48% and 35.71%, respectively. The highest percentages of resistance were obtained for sulfamethoxazole associated with trimethoprim (63.70%), colistin (45.19%) and enrofloxacin (39.26%). Regarding the levels of multidrug resistance, 37.04% of the isolates were resistant to three or more classes of antimicrobials. The most common profile (16%) of multirresistance was GEM-SUT-ENO-COL. The index of multiple resistance to antimicrobials (IRMA) was above 0.2 in 78% of the multiresistant isolates. Out of 135 E. coli isolates, 7.41% was ESBL-producers, of which 50% showed the blaCMY-M2 gene, 40% the blaTEM-1 and 70% the qnrS gene. Of non-ESBL-producing strains resistant to enrofloxacin, 13.04% were positives for qnrS gene. These results demonstrated the presence of fecal contamination in the environment, in addition to high resistance indexes for several antimicrobials, including beta-lactams and fluoroquinolones, which was confirmed by the genetic detection of ESBLs and qnr genes.

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