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Swine meat production integrated with energy cogeneration: challenges and opportunities in using anaerobic biodigestion
Get PDFAs environmental concerns and regulatory requirements increase over time, new alternatives for swine manure disposal emerge. Among them, anaerobic biodigestion is a relevant technology because it reduces the organic load of wastewater before its final disposal and provides economic benefits to farmers with biogas and biofertilizer production. Efficiently managing the anaerobic biodigestion process remains a challenge in developing countries, mainly due to the lack of information from swine meat producers to deal with the complexity of this system. A risk analysis can represent a promising tool for farm assistance because it provides a process overview. Hence, this study reports the results of a process mapping in a swine meat production farm in Minas Gerais, Brazil. This mapping was performed while monitoring biodigestion operational parameters and allowed the identification of the primary causes of process failures and potential environmental impacts. The results showed that anaerobic digestion promotes a relevant environmental gain. However, the need for improved process monitoring, investments in environmental assessment equipment, and technical training for producers also stood out as an improvement opportunity
The influence of different culture media on Pseudomonas aeruginosa, Escherichia coli, and Staphylococcus aureus biofilm formation
Get PDFMicroorganisms such as Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus are frequently isolated in samples of urinary, blood, intestinal, and respiratory infections, among others. These bacteria are also associated with microbial biofilm formation. E. coli, P. aeruginosa, and S. aureus biofilm infections are particularly hard to manage and often associated with nosocomial problems. This study investigated the influence of different culture media on E. coli, P. aeruginosa, and S. aureus biofilm formation. Bacterial performance was evaluated in brain heart infusion broth, Mueller-Hinton broth, or tryptic soy broth, with or without supplementing with different glucose levels (1-5%). The study quantified biofilm biomass and the count of viable biofilm colonies. This is the first study that compares the biofilm formation of E. coli, P. aeruginosa and S. aureus in polystyrene using different culture media and with different glucose concentrations. The most robust growth of E. coli, P. aeruginosa, and S. aureus occurred in brain heart infusion broth supplemented with 5% glucose, Mueller-Hinton broth without glucose, and tryptic soy broth with 2% glucose, respectively. Our data demonstrate that behavioral and morphological characteristics of each bacterium require a specific broth to enhance the growth of these microorganisms. These findings will contribute to future tests for therapeutic alternatives with anti-biofilm potential
Subjective oral health measures in caregivers of patients with autism and Down syndrome: a preliminary study
No full textThis study aimed to address the subjective oral health measures of caregivers of individuals with autism spectrum disorder (ASD) and Down syndrome. This cross-sectional study included 15 caregivers of individuals with ASD (n = 7) and Down syndrome (n = 8). Sociodemographic data, sense of coherence (SOC) (SOC-13 scale), social support (Social Support Scale [MOS-SSS]), oral health-related quality of life (OHRQoL) (OHIP-14), and self-rated oral health assessed on a 5-point Likert scale were collected. A descriptive analysis was performed in addition to correlation analyses (Spearman correlation coefficient). Most primary caregivers were parents of the individual (86.6%). The age of the caregivers ranged between 40 and 59 years (60%). Most caregivers have had 9 to 11 years of education (53.3%). Monthly family income was less than USD 186,28 for ASD caregivers (57.2%) and between USD 327,56 and USD 931,40 for Down syndrome caregivers (50%). Of the caregivers, 33.3% reported good oral health and 33.3% reported neither good nor bad. The average SOC score, social support and OHRQoL was 48.9, 69.3 and 10.9, respectively. The higher the family income, the better the OHRQoL (rs = -0.62, p = 0.014). SOC was correlated with the score of the emotional support domain (rs = 0.54, p = 0.039). It was concluded that caregivers had a strong SOC and high perceived support. Moreover, caregivers did not report a high impact on OHRQoL A better understanding of the caregivers’ protective and coping factors in caring for individuals with disabilities may better promote their quality of life
Spatial variability of soil fertility under agroforestry system and native forest in eastern Amazonia, Brazil
Get PDFThe usage of spatial tools might be helpful in the optimization of decision-making regarding soil management, with technologies that assist in the interpretation of information related to soil fertility. Therefore, the present study evaluated the spatial variability of chemical attributes of the soil under an agroforestry system compared to a native forest in the municipality of Tomé-açu, Eastern Amazon, Brazil. Soil samples were performed at 36 points arranged in a 55 x 55 m grid. The soils were prepared and submitted to analysis in order to determine pH in H2O, exchangeable calcium, magnesium, potassium and aluminium, available phosphorus, potential acidity, organic matter, bases saturation and aluminium saturation. For each soil attribute, the spherical, gaussian and exponential models were adjusted. After the semivariograms fitting, data interpolation for assessment of spatial variability of the variables was performed through ordinary kriging. The spherical and gaussian models were the most efficient models in estimation of soil attributes spatial variability, in most cases. Most of variables presented a regular spatial variability in their respective kriging maps, with some exceptions. In general, the kriging maps can be used, and we can take them as logistical maps for management and intervention practices in order to improve the soil fertility in the study areas. The results principal components indicate the need for integrated management of soil chemical attributes, with localized application of acidity correctors, fertilizers and other types of incomes, using the spatial variability of these fertility variables
Proposal of a non-linear model to adjust in vitro gas production at different incubation times
Get PDFThis work aims to propose a new model named Gompertz-Von Bertalanffy bicompartmental (GVB), a combination of the models Gompertz and Von Bertalanffy. The GVB models is applied to fit the kinetic curve of cumulative gas production (CGP) of four foods (SS – sunflower silage; CS – corn silage; and the mixtures 340SS – 660 gkg-1 of corn silage and 340 gkg-1 of sunflower silage; and 660SS – 340 gkg-1 of corn silage and 660 gkg-1 of sunflower silage). The GVB fit is compared to models Logistic-Von Bertalanffy bicompartmental (LVB) and bicompartmental logistic (BL). All the process studied employed the semi-automatic “in vitro” technique of producing gases used in ruminant nutrition. The gas production readout was performed at times 2, 4, 6, 8, 10, 12, 15, 19, 24, 30, 48, 72, and 96 h. The data generated were used to estimate the models’ parameters by the least squared method with the iterative Gauss-Newton process. The data fit quality of the models was verified using the adjusted coefficient of determination criterion (), mean residual square (MRS), Akaike information criterion (AIC), and mean absolute deviation (MAD). Among the analyzed models, the LVB model presented the best quality of fit evaluators for CS. In contrast, the GVB model showed better quality of fit to describe CGP over time for 340SS, 660SS, and SS, presenting the highest values of () and the lowest values of MSR, AIC, and MAD
Molecular analysis of the prevalence of Acinetobacter baumannii in hospitals and the surrounding environments: a cross-sectional study
Get PDFAcinetobacter baumannii is widely recognized in clinical environments due to its infectious capacity, antimicrobial adaptability, and lethality. Analyzing the prevalence of this agent in intra- and extra-hospital environments may reveal target indicators for appropriate management interventions. In this observational cross-sectional study, we evaluated the prevalence of A. baumannii within hospitals with intensive care units and in their external surroundings in a macro-health region of Brazil. Samples of Columba livia (pigeon) droppings from the external environment of four hospitals (n = 40), from floor surfaces (n = 20), and door handles (n = 20) of different hospital wards were collected based on random sampling, all of which were evaluated for the presence of A. baumannii using polymerase chain reactions (PCR). The sensitivity and specificity of the technique was verified after the collected samples were contaminated with clinical samples positive for A. baumannii. We detected a significantly higher A. baumannii prevalence (87.50%, CI = 71.29–100.00) in samples collected within the hospital environment compared with those obtained from the external environment (12.50%, CI = 0.00–28. 71) (p = 0.003). In addition, samples collected from floor surfaces contained bacterial densities (181.3 ± 11.58) that exceeded those in environmental (93.32 ± 1.56) and door handle (142.70 ± 17.14) samples by 94% and 78.71%, respectively. The findings of this study will enhance our understanding of the spatial distribution of A. baumannii and additionally, validate the efficiency of PCR for diagnosis of this infectious agent
Does the mycotoxin ingestion by beef heifers on feedlot change the productive parameters?
Get PDFIn intensive beef cattle production systems, silage, corn, soy bean, and their coproducts are commonly used as feed. However, these ingredients are highly susceptible to contamination by fungi and mycotoxins, which may lead to immunological challenges and reduce animal production. The aim of the present study was to evaluate the effects of mycotoxin contamination of diet on intake, digestibility, and performance of heifers. Twenty non-pregnant (Nellore) heifers (age, >18 months; initial body weight, 348±30 kg) were used and randomly distributed in two treatments: (1) control (non-contaminated diet) and (2) zearalenone-contaminated diet (300 ppb). The diet comprised 70% corn silage and 30% concentrate. Individual dry matter intake and digestibility were estimated using external and internal markers. Heifer body weight was evaluated every week without fasting to calculate performance. The experimental design was completely randomized. Each animal was considered one experimental unit. Assumptions were tested for variance analyses (error normality, independence of errors, and homogeneity of variances) (p<0.05). There were no differences in dry matter intake (p=0.96) and digestibility (p=0.62). Performance (kg/day) did not vary as a function of zearalenone ingestion (p=0.68). Therefore, contamination of diet with 300 ppb zearalenone did not affect the intake, digestibility, and performance of feedlot-finished heifers.Nos sistemas intensivos de produção de gado de corte, silagems, milho, soja e outros coprodutos são tradicionalmente utilizados como alimentos para animais. Entretante, estes ingredientes são altamente susceptíveis a contaminação por fungos e micotoxinas, com potencial impacto negativo no sistema imunológico do animal e consequente redução de desempenho. O objetivo do presente estudo foi avaliar os efeitos da ingestão de dieta contaminada por micotoxina para novilhas confinadas sobre o consumo, digestibilidade e ganho de peso. Vinte novilhas (Nelore, >18 meses; peso corporal inicial 348±30 kg) foram distribuídas aleatoriamente em dois tratamentos: (1) controle (dieta não contaminada) e (2) dieta contaminada com Zearalenona (300 ppb). A dieta era composta por 70% de silagem de milho e 30% de concentrado. O consumo individual de matéria seca e digestibilidade foram estimados usando marcadores interno e externo. O peso corporal das novilhas foi mensurado semanalmente sem jejum, para cálculo do ganho de peso. Cada animal foi considerado uma unidade experimental. Foram testadas as pressuposições para análise de variância (normalidade dos erros, independência dos erros e homogeneidade das variâncias), e então, esta foi realizada (p<0.05). Não foram constatadas diferenças no consumo de matéria seca (p=0.96) e digestibilidade (p=0.62). O ganho de peso (kg/dia) não foi influenciado pela ingestão de Zearalenona (p=0.68). Assim, a ingestão de dieta contaminada com 300 ppb de Zearalenone não influenciou o consumo, digestibilidade e ganho de peso no confinamento de novilhas de corte
New alternative for adsorption of 2,4-dichlorophenoxyacetic acid herbicide (2,4-D)
Get PDFThe adsorptive capacity of charcoal from the husk of the brazil nut fruit, called “ouriço” (the hard ball with nuts inside) for the herbicide dichlorophenoxyacetic acid (2,4-D) was evaluated. Activated carbons were produced from the brazil nut in a tubular oven at 800 °C and activated with CO2 or water steam. The specific surface area was determined by the Brunauer, Emmett and Teller (BET) method, demonstrating the mean density of micropores. Analysis of N2 adsorption/desorption isotherms was undertaken and the morphology of activated carbons was visualized by Scanning Microscopy (SEM). The activated carbons were successfully obtained and had a specific surface area of 395 m2.g-1 and 401 m2.g-1 after activation with either CO2 or water steam, respectively. The highest pore mean density occurred with a diameter of 1.17 nm for carbons activated in both atmospheres. The graph of the adsorption/desorption isotherms of N2 showed Type I isotherms, regardless of the activation atmosphere. The SEM analysis showed that, for both activation atmospheres, pore formation occurred in the shape of uniform honeycomb craters. Adsorption kinetics followed the pseudo-second order model, indicating chemisorption. Regardless of the activation atmosphere, the activated carbon from the brazil nut “ouriço”, was highly efficient for 2,4-D adsorption.A capacidade adsortiva do carvão vegetal da casca da castanha-do-brasil, denominada “ouriço” para o herbicida ácido diclorofenoxiacético (2,4-D) foi avaliada. Os carvões ativados foram produzidos a partir da castanha-do-brasil em forno tubular a 800°C e ativados com CO2 ou vapor d\u27água. A área superficial específica foi determinada pelo método de Brunauer, Emmett e Teller (BET), demonstrando a maior intensidade dos microporos. A análise das isotermas de adsorção/dessorção de N2 foi realizada e a morfologia dos carvões ativados foi visualizado por Microscopia de Varredura (MEV). Os carvões ativados foram obtidos apresentaram área superficial específica de 395 m2g-1 e 401 m2g-1 após ativação com CO2 ou vapor d\u27água, respectivamente. A maior intensidade de poros ocorreu com diâmetro de 1,17 nm para carvões ativados em ambas as atmosferas. O gráfico das isotermas de adsorção/dessorção do N2 mostrou isotermas do Tipo I, independente da atmosfera de ativação. A análise MEV mostrou que, para ambas as atmosferas de ativação, a formação de poros ocorreu na forma de crateras de favo de mel uniformes. A cinética de adsorção seguiu o modelo de pseudo-segunda ordem, indicando quimissorção. Independentemente da atmosfera de ativação, o carvão ativado do ouriço da castanha-do-brasil, foi altamente eficiente na adsorção de 2,4-D. O carvão ativado com vapor d\u27água apresentou resultados superiores em relação à quantidade de herbicida adsorvido nos primeiros minutos
Biochemical and insecticidal efficacy of clove and basil essential oils and two photosensitizers and their combinations on Aphis gossypii glover (Hemiptera: Aphididae)
Get PDFThe present study investigates the insecticidal and biochemical effects of two essential oils (EOs) and two photosensitizers against cotton aphids in a laboratory setting. The EOs evaluated were clove (Syzygium aromaticum L.) and basil (Ocimum basilicum), while the photosensitizers were rose bengal and rhodamine B. The individual median lethal concentrations (LC50) revealed that clove was ~4.44 times more potent than basil, and rhodamine B was ~1.34 times more potent than rose bengal. The mortality rates increased using higher concentrations of the photosensitizers and prolonging exposure time to sunlight. The most effective combination against adult aphids was found to be a mixture of sub-lethal concentrations of clove and rhodamine B, resulting in a mortality rate of 92.31%. Conversely, the combination of basil and rose bengal exhibited the lowest efficacy with a mortality rate of 33.33%. Biochemical analyses indicate that Rhodamine B, basil, and the basil-rhodamine B mixture (mixture C) significantly reduced trehalase activity. However, the protease activity significantly increased in aphids treated with rose bengal, clove, and the clove-rose bengal mixtures (mixtures A and B). The lipase activity is notably decreased upon treatment with rhodamine B and clove. Glutathione S-transferase (GST) activity decreased in aphids treated with rose bengal and the basil-rhodamine B mixtures (mixtures C and D), suggesting that GST did not play a role in detoxifying these compounds, thereby explaining the susceptibility of A. gossypii. Overall, the combination of essential oils and photosensitizers has demonstrated a synergistic effect in controlling Aphis gossypii, offering great potential as an effective strategy for aphid management
Microbial biostimulants as alternatives for the rooting of olive tree cuttings
Get PDFCurrently, southern Minas Gerais (MG) state is an important producer of different olive tree (Olea europaea L.) cultivars because, in this region, the plants can differentiate the buds to produce flowers and fruit. To stimulate the rooting of cuttings, the synthetic hormone indole-3-butyric acid (IBA) at a concentration of 3 g L−1 is used commercially. However, few studies have investigated arbuscular mycorrhizal fungi (AMF), isolated or combined with rhizobacteria, as a biotechnological tool to produce hormones that function in the rooting of olive tree cuttings. The aim of this study was to evaluate the capacity of different AMF species (Rhizophagus clarus, Gigaspora rosea, or Acaulospora scrobiculata), combined or not with IBA or rhizobacteria, to promote the rooting of three olive tree cuttings (Arbequina, Grappolo 541, and Maria da Fé) with potential for cultivation in this region. For this, three experiments were conducted at the Experimental Farm of EPAMIG in Maria da Fé (MG), and the rooting potential of the olive tree cuttings inoculated with I) AMF, II) AMF combined with increasing doses of IBA, and III) AMF combined with three isolates of rhizobacteria was evaluated. The inoculation of olive tree cuttings of cultivars Arbequina, Grappolo 541, and Maria da Fé with Rhizophagus clarus, Gigaspora rosea, or Acaulospora scrobiculata combined or not with IBA or rhizobacteria did not significantly promote rooting. Alternative forms of rooting olive tree cuttings are still a challenge, and further studies for standardizing methodologies and experimental conditions are required.Atualmente, o sul de Minas Gerais (MG) é um importante produtor de diferentes cultivares de oliveira (Olea europaea L.), pois nessa região é possível haver diferenciação dos brotos das plantas em flores e, posteriormente, frutos. Para estimular o enraizamento das estacas, o hormônio sintético ácido indol-3-butírico (AIB), na concentração de 3 g L-1, tem sido utilizado comercialmente. No entanto, poucos estudos investigaram fungos micorrízicos arbusculares (FMA), isolados ou combinados com rizobactérias, como uma ferramenta biotecnológica para a produção de hormônios que atuam no enraizamento de estacas de oliveiras. O objetivo deste trabalho foi avaliar a capacidade de diferentes espécies de FMA (Rhizophagus clarus, Gigaspora rosea ou Acaulospora scrobiculata), combinadas ou não com AIB ou rizobactérias, de promover o enraizamento de estacas de 3 cultivares de oliveira (Arbequina, Grappolo 541 e Maria da Fé) com potencial para cultivo nessa região. Para isso, três experimentos foram conduzidos na Fazenda Experimental da EPAMIG em Maria da Fé (MG), avaliando-se o potencial de enraizamento de estacas de oliveiras inoculadas com I) FMA, II) FMA combinados com doses crescentes de AIB e III) FMA combinados com três isolados de rizobactérias. A inoculação de estacas de oliveira das cultivares Arbequina, Grappolo 541 e Maria da Fé com Rhizophagus clarus, Gigaspora rosea ou Acaulospora scrobiculata, combinadas ou não com IBA ou rhizobacteria, não promoveu significativamente o enraizamento de estacas de oliveira. Formas alternativas de enraizamento de estacas de oliveira ainda são um desafio, sendo necessários mais estudos para padronizar metodologias e condições experimentais