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In this work, silica nanospheres were used as support for gold nanoparticles and applied for bisphenol A electrochemical detection. The development of new silica-supported materials has attracted increasing attention in the scientific world. One approach of interest is using silica nanospheres as support for gold nanoparticles. These materials have a variety of applications in several areas, such as electrochemical sensors. The obtained materials were characterized by solid-state UV-vis spectroscopy, electron microscopy, X-ray diffraction, and electrochemical techniques. The electrode modified with AuSiO2700/CHI/Pt was applied as an electrochemical sensor for BPA, presenting an oxidation potential of 0.842 V and a higher peak current among the tested materials. The AuSiO2700/CHI/Pt electrode showed a logarithmic response for the detection of BPA in the range of 1-1000 nmol L-1, with a calculated detection limit of 7.75 nmol L-1 and a quantification limit of 25.8 nmol L-1. Thus, the electrode AuSiO2700/CHI/Pt was presented as a promising alternative to an electrochemical sensor in the detection of BPA.

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AIMS: This study aimed to evaluate the toxicity and humoral and cellular immune response of three heterologous vaccines against Leishmania infantum, yet containing synthetic peptides from Leishmania major in the experimental model in hamsters. METHODS AND RESULTS: Through bioinformatics analyses, two Leishmania major Gp63 peptides were predicted and selected for vaccine formulations. Hamsters were divided into four groups, with each group receiving doses of three vaccine formulations containing HLA-DR1 or HLA-A2 peptides plus MontanideTM or both associated with the adjuvant. The animals received three vaccine doses and were evaluated for toxicity after each dose, in addition to being analysed for the production of antibodies and lymphoproliferation on day 211 after the last vaccine dose. Peptides predicted in association with oily adjuvant induced a humoral response and strong lymphoproliferation to Leishmania infantum antigen-specific stimulation.

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We conducted an in silico analysis to search for important genes in the pathogenesis of Caseous Lymphadenitis (CL), with prospects for use in formulating effective vaccines against this disease. For this, we performed a survey of proteins expressed by Corynebacterium pseudotuberculosis, using protein sequences collected from the NCBI GenPept database and the keywords "caseous lymphadenitis" and "Corynebacterium pseudotuberculosis" and "goats". A network was developed using the STRING 10 database, with a confidence score of 0.900. For every gene interaction identified, we summed the interaction score of each gene, generating a combined association score to obtain a single score named weighted number of links (WNL). Genes with the highest WNL were named "leader genes". Ontological analysis was extracted from the STRING database through Kyoto Encyclopedia of Genes and Genomes (KEGG) database. A search in the GenPept database revealed 2,124 proteins. By using and plotting with STRING 10, we then developed an in silico network model comprised of 1,243 genes/proteins interconnecting through 3,330 interactions. The highest WNL values were identified in the rplB gene, which was named the leader gene. Our ontological analysis shows that this protein acts effectively mainly on Metabolic pathways and Biosynthesis of secondary metabolites. In conclusion, the in silico analyses showed that rplB has good potential for vaccine development. However, functional assays are needed to make sure that this protein can potentially induce both humoral and cellular immune responses against C. pseudotuberculosis in goats.

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Phytase plays a prominent role in monogastric animal nutrition due to its ability to improve phytic acid digestion in the gastrointestinal tract, releasing phosphorus and other micronutrients that are important for animal development. Moreover, phytase decreases the amounts of phytic acid and phosphate excreted in feces. Bioinformatics approaches can contribute to the understanding of the catalytic structure of phytase. Analysis of the catalytic structure can reveal enzymatic stability and the polarization and hydrophobicity of amino acids. One important aspect of this type of analysis is the estimation of the number of ß-sheets and α-helices in the enzymatic structure. Fermentative processes or genetic engineering methods are employed for phytase production in transgenic plants or microorganisms. To this end, phytase genes are inserted in transgenic crops to improve the bioavailability of phosphorus. This promising technology aims to improve agricultural efficiency and productivity. Thus, the aim of this review is to present the characterization of the catalytic structure of plant and microbial phytases, phytase genes used in transgenic plants and microorganisms, and their biotechnological applications in animal nutrition, which do not impact negatively on environmental degradation.

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O propósito deste trabalho foi avaliar a produção de biogás obtido com a biodigestão anaeróbia dos resíduos sólidos provenientes de biotério. Para tanto, foram confeccionados biodigestores a partir de bombonas plásticas com capacidade máxima para 200 L, providos de gasômetro com termômetro e orifício com mangueira para eliminação do biogás. Cada biodigestor foi carregado com 8% de sólidos totais de resíduo do biotério separadamente, isto é, resíduo de: coelho, cobaia, camundongo e hamster, sendo o restante completado com água para um volume final de aproximadamente 150 L. Em paralelo, foi montado um biodigestor carregado com a mistura de todos os dejetos do biotério. A biodigestão destas misturas de resíduos sólidos e água ocorreu sob temperatura ambiente de 30 (± 5) °C e temperatura interna de 33 (± 3) °C. Ao término do trabalho, a produção de biogás apresentou-se satisfatória, com produção mínima de 70,95 L.Kg-1 de dejeto de hamster, sendo a produção máxima oriunda dos dejetos de camundongos com 101,51 L.Kg-1, seguida por dejetos de cobaias com 91,91 L.Kg-1 e coelhos com 85,58 L.kg-1. Assim sendo, sugere-se que o processo de biodigestão anaeróbia aparenta ser eficiente para a produção de biogás.

The purpose of this study was to evaluate the production of biogas obtained from anaerobic digestion of solid waste from animal facilities. Plastic digesters with a capacity of 200 L, equipped with a thermometer and a hole with the gas hose for disposal were used. Each digester was loaded with 8% of total solid waste in the animal house separately, i.e., residues from rabbit, guinea pig, mouse and hamster, the remainder being completed with water to a final volume of about 150 L. Another digester loaded with a mixture of all the waste from the animal house was mounted in parallel. The bio digestion of such mixtures was conducted at room temperature at 30 (± 5) °C, and internal temperature of 33 (± 3) °C. At the end of the work, a satisfactory production of biogas was reached, with a minimum of 70.95 L.Kg-1 of hamster waste and a maximum production derived from the mice waste, 101.51 L.Kg-1, followed by guinea pigs waste, 91.91 L.Kg-1, and rabbits waste, 85.58 L.Kg-1. Therefore, it is suggested that the anaerobic digestion process seems to be efficient for the production of biogas.

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This study evaluated composting as a means of treating wastes from rabbits, guinea pigs, mice and hamsters from animal care facilities and its subsequent use for agricultural purposes. We built six compost windrows with 500kg solid wastes mixed with 221.65kg of cotton waste each, which gave a C:N ratio of nearly 30:1. Chemical, microbiological and parasitological analyses of the wastes and the composts were performed before and after treatment. Temperature and pH were measured inside the windrows throughout the experiment. The initial temperature of 28°C increased to a peak of 60°C and decreased to stabilization within approximately 100 days. The pH values oscillated between 6.5 and 8.0, the range indicated to assure pathogen removal and compost quality. At the end of the experiment, over 90% of Escherichia coli, Salmonella sp, protozoan oocysts and helminth eggs were efficiently eliminated in most of the composts. Chemical analyses detected suitable contents of macro and micronutrients and acceptable levels of heavy metals in the composts. We conclude that composting is an efficient method to treat the solid wastes produced by the studied species held in animal care facilities. It eliminates or reduces microorganism content, producing class B biosolids that can be used with restriction in agricultural practices.

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The objective of this study was to monitor temperature and pH in composting windrows constituted of rabbit, guinea pig, mouse and hamster wastes. Wastes from these laboratory animals were mixed to cotton wastes to produce 721.65 kg of composts. There were constructed 6 composting windrows and they were monitored daily for temperature and pH. Composts were watered daily until humidity level was near 55%. The compost piles were turned every 15 days. All the windrows passed through a thermophilic phase followed by a mesophilic phase, and maximum temperature was near 60°C. The pH values ranged from 6 to 8 in most of the windrows. In conclusion, characteristics of the compost studied such as humidity, pH, color and absence of foul odors makes it suitable for agricultural use.

Teve-se por objetivo monitorar a temperatura e pH de leiras de compostagem formadas a partir de dejetos de coelhos, cobaias, camundongos e hamsters. Foram misturados resíduos de animais de laboratório e resíduos de algodão, para uma quantidade de 721,65 kg. Foram montados 6 leiras de compostagens, as quais foram monitoradas diariamente quanto a pH e temperatura. As compostagens foram molhadas diariamente, até atingirem umidade próxima a 55%. As reviragens das compostagens foram realizadas a cada 15 dias. Verificou-se que em todas as compostagens ocorreu uma fase termofílíca e outra mesofílica, com temperatura máxima próxima a 60°C. Os valores de pH oscilaram dentro da faixa de 6 a 8 na maioria das leiras. Conclui-se que o composto estudado apresentou características desejáveis para a agricultura, como umidade, pH, coloração e ausência de maus odores.

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