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1.
Environ Sci Pollut Res Int ; 30(46): 102222-102230, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37667116

RESUMO

The most common alternative for the management and valorization of rice processing waste is the combustion of rice husk (RH) for energy generation. The environmental risk assessment of the ash generated during the combustion of the RH to obtain energy has remained understudied. Disposal of rice husk ash (RHA) on agricultural land is the most common outcome, which could pose a risk to both natural ecosystems and human health. The objective of this study was to characterize the physicochemical composition and the phytotoxicity, cytotoxicity, and genotoxicity of RHA obtained from three distinct combustion processes. The evaluation processes were 800-900 °C in up to 5 min (I), 800-900 °C in 15-20 min (II), and 600-700 °C in 15-20 min (III). Furthermore, the content, pH, and concentrations of Al, Cd, Cu, Fe, Mg, Mn, Mo, Na, Ni, and Ti present in the ashes were determined. The germination index for two vegetable seeds was subsequently evaluated. By measuring the mitotic index and frequency of chromosomal aberrations, the cytotoxicity and genotoxicity were determined. It was observed that RHA produced by combustion of RH at higher combustion temperatures for an extended period exhibited different physicochemical properties, in addition to higher levels of phytotoxicity, cytotoxicity, and genotoxicity.

2.
Environ Sci Pollut Res Int ; 30(5): 12872-12882, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36114968

RESUMO

Inorganic forms of As (arsenite - As(III) and arsenate - As(V)) are prevalent in soil and recognized for their high toxicity. Once in the soil, these forms of As can compromise key organisms for ecological processes, such as earthworms. The aim of the study was to evaluate the toxicity of arsenite and arsenate in the Californian earthworm Eisenia andrei exposed in natural soil and tropical artificial soil (TAS). Adverse effects were evaluated using avoidance test, acute toxicity test, and a sublethal concentration test to assess biochemical parameters. LC50 values for arsenite were 21.27 mg/kg in natural soil and 19.0 mg/kg in TAS and for arsenate were 76.18 mg/kg in natural soil and above 120 mg/kg in TAS. In the avoidance test, this behavior was shown to be significantly higher in the natural soil and for earthworms exposed to arsenite, while total antioxidant capacity, glutathione levels, lipid damage, and DNA damage were significantly higher in animals exposed to arsenite, but without differences in relation to the two types of soil tested. Animals exposed to As(V) showed increased activity of enzymes related to glutathione metabolism. The results obtained in the present study show the impact of As exposure on the health of the Californian earthworm E. andrei, especially in the form of arsenite, and alert the public authorities that legal limits should, whenever possible, consider the soil properties and also the different chemical species of the contaminants.


Assuntos
Arsenitos , Oligoquetos , Poluentes do Solo , Animais , Solo/química , Arseniatos/toxicidade , Arseniatos/metabolismo , Arsenitos/toxicidade , Arsenitos/metabolismo , Poluentes do Solo/análise
3.
Eng. sanit. ambient ; 27(1): 47-53, jan.-fev. 2022. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1364821

RESUMO

ABSTRACT One of the major drawbacks of this final disposal technique is leachate production, which occurs due to the degradation of organic matter and rainwater percolation. The leachate composition is quite varied, with high organic load and various compounds that may be toxic to the environment. To reduce the polluting potential of the leachate, it must be subjected to an appropriate treatment. Biological treatments are widely used in the treatment of leachate, although these technologies have some drawbacks. As an alternative to conventional biological treatments, rotating biological reactors are used. The objective of this study was to determine the efficiency of a pilot scale rotating biological reactors in the removal of biochemical oxygen demand, chemical oxygen demand, and phosphorus from the landfill leachate. Effluent toxicity and rotating biological reactors's ability to remove this toxicity were also verified by calculating the germination index of lettuce (Lactuca sativa) and cucumber (Cucumis sativus) seeds. The reactor showed an average efficiency of 75.99% of biochemical oxygen demand removal, 33.53% of chemical oxygen demand removal, and 16.04% of phosphorus removal. In fact, the cucumber and lettuce seeds proved sensitive to the toxicity of the effluent. For crude leachate, the germination index values of lettuce and cucumber were 13.28 and 49.61%, respectively. In this study, rotating biological reactors obtained a good efficiency in the removal of toxicity from leachate. The germination index of the seeds for the treated effluent was 60.9% for lettuce and 82.49% for cucumber.


RESUMO Diante do crescimento populacional acelerado e do desenvolvimento econômico, grande quantidade de resíduos tem sido gerada nos grandes centros urbanos. Esses resíduos devem ser coletados e dispostos adequadamente, sendo os aterros sanitários os locais mais adequados para a sua disposição. Um dos grandes inconvenientes dessa técnica de disposição final é a produção de um líquido lixiviado, proveniente da degradação da matéria orgânica e da percolação da água da chuva. A composição do lixiviado é bastante variada, com elevada carga orgânica e diversos compostos que podem ser tóxicos ao meio ambiente. Para determinar a toxicidade do lixiviado são amplamente utilizados testes fitotoxicológicos, como o índice de germinação de sementes. Com o intuito de reduzir o potencial poluidor do lixiviado, este deve ser submetido a um tratamento adequado. Tratamentos biológicos são bastante utilizados, mas possuem algumas desvantagens. Como alternativa aos tratamentos biológicos convencionais, surgem os reatores biológicos rotatórios. O objetivo deste estudo foi determinar a eficiência de uns reatores biológicos rotatórios em escala piloto na remoção da demanda bioquímica de oxigênio, da demanda química de oxigênio e de fósforo do lixiviado do aterro. Também foi verificada a toxicidade do efluente e a capacidade dos reatores biológicos rotatórios para remover essa toxicidade por meio do cálculo do índice de germinação de sementes de alface (Lactuca sativa) e pepino (Cucumissativus). O reator utilizado neste trabalho obteve eficiência média de 75,99% de remoção de demanda bioquímica de oxigênio, 33,53% de remoção de demanda química de oxigênio e 16,04% de remoção de fósforo. As sementes de alface e pepino mostraram-se bastantes sensíveis à toxicidade do efluente. Para o lixiviado bruto, os índices de germinação da alface e do pepino foram, respectivamente, 13,28 e 49,61%. Neste estudo, os reatores biológicos rotatórios obtiveram boa eficiência na remoção da toxicidade do lixiviado. O índice de germinação das sementes para o efluente tratado foi de 60,9% para a alface e de 82,49% para o pepino.

4.
Artigo em Inglês | MEDLINE | ID: mdl-34370597

RESUMO

This work aimed to evaluate the composting of the mixture of residues from fish filleting, using sawdust as a structuring material as an alternative for stabilization, through physical-chemical analysis and phytotoxicity. The experiment was carried out in a composter 1.10 m long, 1.50 m wide, and 1.20 m high and presenting 2.50 m in total height, which received the mixture of fish filleting wastes and sawdust in a5:3 ratio, respectively. The results demonstrated that composting in cells is an efficient alternative for the decomposition of the mixture of fish filleting and sawdust residues. The rapid decomposition of fish waste and the low C/N ratio harms the development of thermophilic microorganisms during the composting of the mixture of fish filleting and sawdust residues. The compaction of the sawdust layers and the absence of stirring in the composting method in cells collaborate for the compost to need a time greater than 60 days to be recommended as simple organic fertilizer. The biomass stirring is necessary so that sawdust can be considered a good structuring agent. The phytotoxicity test should be taken into account by the Normative Instruction n° 25/2009 as an indicator of compost maturity.


Assuntos
Compostagem , Animais , Fertilizantes , Solo , Madeira
5.
J Environ Manage ; 291: 112698, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-33971513

RESUMO

Seed germination tests have been widely used in recent years to indicate the toxicity levels of samples of organic compounds, biosolids, residues and effluents. Lactuca sativa L, commonly known as lettuce, has been one of the main indicative species for these tests due to its high sensitivity to low levels of toxicity, when compared to other seeds and also because it is cultivated worldwide. Although this type of analysis or essay is being widely used, it is necessary to reflect on the various adaptations of methods used by different researchers worldwide. This work presents an innovative methodology that makes it possible to compare the different phytotoxicity methods currently used in the world, through four stages that include the coefficient of variation (CV) as the main classification criterion, also counting on an eliminatory criterion. The existence of a significant difference (P value < 0.05) between the evaluated tests was proven. The phytotoxicity test that presented the lowest CV was T8 (test with lettuce seeds at 25 °C, 60 min agitation, resting overnight, 5 mL of sample on the plate, 90 mm size plate). It has concluded that not all adaptations of this type of test are reliable. It has also concluded that there is a lack of standardization for the phytotoxicity test on a global scale, which makes the various researchers in the field end up promoting variations, adaptations for the phytotoxicity test; therefore, there is an urgent need for ways to compare these variations, as the innovation proposed by this work. With a single standard methodology, we conclude that it will make it possible to compare phytotoxicity in samples directly between countries and continents, being able to generate a worldwide panorama of phytotoxicity, publicizing and comparing the standardized phytotoxicity levels in each region.


Assuntos
Germinação , Poluentes do Solo , Raízes de Plantas , Sementes
6.
Eng. sanit. ambient ; 25(2): 271-279, mar.-abr. 2020. tab, graf
Artigo em Português | LILACS-Express | LILACS | ID: biblio-1098209

RESUMO

RESUMO Os resíduos de serviços de saúde (RSS) são todos aqueles resíduos gerados nos serviços que prestam atendimento à saúde humana ou animal. Os RSS são classificados em cinco grupos (Grupo A, Grupo B, Grupo C, Grupo D e Grupo E), dos quais uma parcela apresenta periculosidade. A legislação brasileira recomenda que os resíduos pertencentes ao Grupo D sejam reciclados. Contudo, com base na má segregação existente, o encaminhamento desses materiais representa riscos aos profissionais que manejam os resíduos intra e extraestabelecimentos de saúde, incluindo os trabalhadores que atuam junto às cooperativas de triagem de materiais recicláveis. Nesse contexto, este trabalho teve como objetivo verificar a presença de RSS destinados inadequadamente às cooperativas de triagem de materiais recicláveis de um município da zona Sul do Rio Grande do Sul. Para tanto, foi realizada uma caracterização quali-quantitativa dos RSS incidentes nas cinco cooperativas do município durante o período de quatro semanas. A partir dos resultados obtidos, verificou-se a presença de RSS no programa de coleta seletiva (PCS) municipal e, também, que a quantidade incidente varia conforme a cooperativa estudada e a semana avaliada. Ao final das caracterizações, foram quantificados 36,23 kg de RSS entre todas as cooperativas. Tais resultados indicam falhas na segregação e na destinação de RSS, seja pela população e/ou pelos estabelecimentos de saúde, além de evidenciarem a fragilidade existente no PCS do município. À vista disso, torna-se necessária a implementação de políticas públicas, tanto educativas quanto de fiscalização, que sejam capazes de assegurar maior segurança no âmbito de trabalho das cooperativas de triagem de materiais recicláveis.


ABSTRACT Healthcare waste (HCW) is all the waste generated by human or animal health care activities. HCW is classified into five groups, of which a portion presents hazardousness. Brazilian legislation recommends that waste belonging to Group D be recycled. However, based on the poor existing waste segregation, the forwarding of these materials presents risks to the professionals who handle them inside and out of health care facilities, including the workers within recyclable material waste picker cooperatives. In such a context, this study aimed to investigate the presence of HCW inappropriately sent to waste pickers cooperatives of a municipality in the south of Rio Grande do Sul. To this end, a qualitative and quantitative characterization of HCW incidence in the five cooperatives of the municipality was performed during the period of four weeks. From the results obtained, it was possible to verify the presence of HCW in the municipal selective waste collection program and that HCW quantities vary according to the waste pickers cooperative studied and the week being evaluated. At the end of the characterizations, 36.23 kg of HCW were quantified amongst all the cooperatives. Such results indicate flaws in HCW segregation and destination, either by the population and/or by health care facilities, in addition to showing the fragility in the municipality's selective waste collection program. In view of this, it is necessary to implement public policies, both educational and supervisory, that can ensure greater safety in the work environment of recyclable material waste picker cooperatives.

7.
Bull Environ Contam Toxicol ; 101(5): 678-683, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30327819

RESUMO

The aim of this study was to evaluate the phytotoxicity of raw and treated effluents from a parboiling rice industry in the south of Brazil. The evaluation included 19 physicochemical parameters and a phytotoxicity test using lettuce and cucumber seeds as bioindicators. The germination index (GI) of both seeds was decreased when in contact with the raw effluent (p < 0.05) and with the treated effluent reduced the GI of cucumber seeds (p < 0.05) and the root length (RL) of lettuce seeds (p < 0.05). For lettuce seeds exposed to the treated effluent there was a negative correlation (p < 0.05) between RL and Mn (- 0.82) and between GI and Fe (- 0.68). For cucumber seeds in the raw effluent, the Fe showed negative correlation (p < 0.05) with seed germination (- 0.75), but, in the treated effluent, their GI presented positive correlation (0.61) with the ammoniacal-N (p < 0.05). The results indicated that both effluents showed phytotoxicity for lettuce and cucumber seeds.


Assuntos
Germinação/efeitos dos fármacos , Oryza , Águas Residuárias/análise , Brasil , Sementes
8.
Food Sci. Technol (SBCTA, Impr.) ; 38(1): 91-97, Jan.-Mar. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-892244

RESUMO

Abstract Flotation sludge (FS) is produced in huge amounts at slaughterhouses in western Santa Catarina, Brazil. This waste is rich in plant nutrients and a valuable resource for soil amendments. Five FS composts were tested as a replacement for chemical fertilizers (QF), namely T1 (75% poultry manure (PM) and 25% sawdust (SD)); T2 (50% PM and 50% SD); T3 (25% PM and 75% SD); T4 (100% PM and 0% SD); and T5 (0% PM x 100% SD). For lettuce plants, treatments containing composted FS resulted in an increased number of leaves, leaf area and leaf fresh weight (LFW). T1 presented the best results with increases of 1.4 fold in LFW compared to plants supplemented with QF. T2 was the most effective treatment for radish with the best results of root fresh weight and root diameter. Although T4 had the highest nitrogen content, it did not present the best results in growth performance for lettuce or radish. The presence of higher proportions of SD in composts (25% for lettuce and 50% for radish) improved the physical characteristics of the soil and proved to be a more balanced compost.

9.
Semina cienc. biol. saude ; 39(1): 29-40, jan. 2018. tab
Artigo em Português | LILACS | ID: biblio-988013

RESUMO

Alguns pesquisadores e laboratórios clínicos utilizam apenas uma técnica para detecção de parasitos intestinais, podendo isto subestimar os achados. Enteroparasitos afetam principalmente populações com vulnerabilidade social, como os catadores. Alguns destes trabalhadores se reúnem em cooperativas, melhorando a condição de trabalho e o rendimento mensal, porém ainda não é o adequado, sendo por vezes insalubre. Nosso objetivo foi verificar a prevalência de enteroparasitos e comparar duas técnicas parasitológicas em suas medidas de efeito em catadores de material reciclável que trabalhavam em cooperativas no Sul do Brasil. Três amostras de fezes de 48 catadores, de seis cooperativas, foram coletadas em dias alternados, para a análise de parasitos. Duas técnicas de concentração de amostra foram utilizadas (Faust e Ritchie) e testadas para verificação da melhor a ser utilizada. A prevalência de parasitos em catadores foi de 62,5% (30/48) utilizando as duas técnicas em paralelo, sendo que quando utilizadas sozinhas, essa prevalência foi menor. Diagnosticaram-se helmintos e protozoários, tanto patogênicos quanto comensais. A partir da análise estatística, provou-se que as técnicas parasitológicas fornecem melhores resultados quando utilizadas em paralelo, ou seja, quando utilizamos as duas técnicas juntas e em três amostras de fezes.


Some researchers and clinical laboratories use just one technique for the detection of enteroparasites, allowing substandard findings. Enteroparasites mostly affect the socially vulnerable population, like the waste pickers. Some of these workers are gathered in cooperatives where work conditions and monthly wage are better. However, this environment is still not adequate being, sometimes, unsanitary. The objective was to study the enteroparasite prevalence and compare the two parasitological techniques in their effect measure in recyclable waste picker who were working in cooperatives in the south of Brazil. Three stool samples from 48 pickers from six cooperatives were collected in alternate days for parasite analysis. Two sample concentration techniques were used (Faust and Ritchie) and tested to verify which was the best to use. The parasite prevalence in waste picker was 62.5% (30/48), using the two techniques concurrently. When used individually, the prevalence was lower. Commensal and pathogenic helminths and protozoan were diagnosed. From the statistical analysis, it was proved that the parasitological techniques provide better results when used concomitantly, that is, when using the two techniques at the same time in three stool samples.


Assuntos
Humanos , Parasitos , Saúde Pública , Reciclagem , Catadores , Enteropatias Parasitárias
10.
J Environ Manage ; 207: 141-150, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29156437

RESUMO

The negative environmental impacts associated with home composting may be due to the absence of a defined operation criteria for the degradation process. In addition to the potentially low environmental impact in terms of energy and water usage, which is minimal to the manufacture of the composting unit and avoiding the processing and transportation of waste or byproduct, composting at home can also promote a reduction in the emission of unpleasant gases. The proportion of the food waste and bulking agents in the composting mixture may be decisive to fulfill good practices of waste stabilization. The aim of this study was to investigate how different ratios of bulking agent and organic household waste can affect the progress and outcome of the composting process. Three treatments, varying in the ratio of rice husk: raw fruit and vegetable leftovers (70:30, 50:50, 30:70; v:v) were used in a home composting system on a pilot scale. Results show that the proportion of starting materials used in the composting mixture influenced the degradation of organic matter, nitrogen dynamics of the process and its toxicity on germinating plants. The proportions with greater amounts of food waste had higher concentrations of mineral matter, higher peak temperature, and a better initial carbon-to-nitrogen ratio, while the proportion containing 70% of bulking agent lacked odors and leachate generation and showed a low nitrogen loss. A higher proportion of food waste presented better conditions for microbiological development and less time to obtain characteristics of matured composts. A higher proportion of bulking agents resulted in favorable conditions for household handling and less potential for environmental impacts.


Assuntos
Compostagem , Alimentos , Eliminação de Resíduos , Carbono , Nitrogênio , Solo , Temperatura
11.
Sci Total Environ ; 592: 86-90, 2017 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-28314134

RESUMO

This study evaluated the phytotoxic effects of raw and treated effluents from a swine slaughterhouse on cucumber and lettuce seeds and determined correlations among physicochemical characteristics of such effluents and the germination of seeds used as bioindicators. Physicochemical parameters were characterized for both effluents and their phytotoxicity was determined through the germination index (GI), the root length (RL) and the number of germinated seeds (SG) for both plant species. The effluents treatment system was efficient to reduce the concentration of some physicochemical parameters to levels within those recommended by the Brazilian legislation, except for P, ammoniacal N and TKN concentration. Although phytotoxicity of the treated effluent was less in comparison to the raw effluent, the GI for cucumber and lettuce seeds submitted to each of the tested effluents was lower than 80%. Thus, both effluents were phytotoxic for the tested bioindicators (p<0.05). For lettuce seeds, the GI presented negative correlations (p<0.05) with the total Kjeldahl N (-0.93) and the surfactants concentration (-0.83) in the raw effluent. The Zn concentration in the treated effluent showed a negative correlation (p<0.05) with the GI of both lettuce (-0.63) and cucumber seeds (-0.64). Therefore, effluents from swine slaughterhouses may impair the germination of the evaluated plant species if used for agricultural purposes.


Assuntos
Matadouros , Germinação/efeitos dos fármacos , Esterco , Sementes/efeitos dos fármacos , Resíduos/efeitos adversos , Animais , Brasil , Cucumis sativus/efeitos dos fármacos , Resíduos Industriais/efeitos adversos , Suínos
12.
Braz. j. microbiol ; 47(3): 675-679, July-Sept. 2016. tab, graf
Artigo em Inglês | LILACS | ID: lil-788961

RESUMO

ABSTRACT The need for cleaner sources of energy has stirred research into utilising alternate fuel sources with favourable emission and sustainability such as biodiesel. However, there are technical constraints that hinder the widespread use of some of the low cost raw materials such as pork fatty wastes. Currently available technology permits the use of lipolytic microorganisms to sustainably produce energy from fat sources; and several microorganisms and their metabolites are being investigated as potential energy sources. Thus, the aim of this study was to characterise the process of Staphylococcus xylosus mediated fermentation of pork fatty waste. We also wanted to explore the possibility of fermentation effecting a modification in the lipid carbon chain to reduce its melting point and thereby act directly on one of the main technical barriers to obtaining biodiesel from this abundant source of lipids. Pork fatty waste was obtained from slaughterhouses in southern Brazil during evisceration of the carcasses and the kidney casing of slaughtered animals was used as feedstock. Fermentation was performed in BHI broth with different concentrations of fatty waste and for different time periods which enabled evaluation of the effect of fermentation time on the melting point of swine fat. The lowest melting point was observed around 46 °C, indicating that these chemical and biological reactions can occur under milder conditions, and that such pre-treatment may further facilitate production of biodiesel from fatty animal waste.


Assuntos
Animais , Staphylococcus/metabolismo , Biocombustíveis , Fermentação , Resíduos Industriais , Biotransformação , Indústria Alimentícia , Carne Vermelha
13.
Braz J Microbiol ; 47(3): 675-9, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27266633

RESUMO

The need for cleaner sources of energy has stirred research into utilising alternate fuel sources with favourable emission and sustainability such as biodiesel. However, there are technical constraints that hinder the widespread use of some of the low cost raw materials such as pork fatty wastes. Currently available technology permits the use of lipolytic microorganisms to sustainably produce energy from fat sources; and several microorganisms and their metabolites are being investigated as potential energy sources. Thus, the aim of this study was to characterise the process of Staphylococcus xylosus mediated fermentation of pork fatty waste. We also wanted to explore the possibility of fermentation effecting a modification in the lipid carbon chain to reduce its melting point and thereby act directly on one of the main technical barriers to obtaining biodiesel from this abundant source of lipids. Pork fatty waste was obtained from slaughterhouses in southern Brazil during evisceration of the carcasses and the kidney casing of slaughtered animals was used as feedstock. Fermentation was performed in BHI broth with different concentrations of fatty waste and for different time periods which enabled evaluation of the effect of fermentation time on the melting point of swine fat. The lowest melting point was observed around 46°C, indicating that these chemical and biological reactions can occur under milder conditions, and that such pre-treatment may further facilitate production of biodiesel from fatty animal waste.


Assuntos
Biocombustíveis , Fermentação , Resíduos Industriais , Staphylococcus/metabolismo , Animais , Biotransformação , Indústria Alimentícia , Carne Vermelha
14.
Ciênc. rural ; 39(4): 1189-1194, jul. 2009. graf, tab
Artigo em Português | LILACS | ID: lil-519117

RESUMO

O objetivo deste trabalho foi avaliar a eficácia do uso de cal virgem (CaO) para a redução de Salmonella spp. e Clostridium spp. em cama de aviário. Foram aplicados quatro tratamentos: T1- sem adição de cal virgem (controle), T2- aplicação de cal virgem na dose de 300g m-2, T3- aplicação de cal virgem na dose de 600g m-2 e T4- aplicação de cal virgem na dose de 900g m-2. Os valores médios observados para o pHda cama após o 12o dia de aplicação de cal virgem foram 8,95 e 9,91, 10,75 e 11,11 para os tratamentos 1, 2, 3 e 4,respectivamente. O número mais provável Log10 (UFC) de Salmonella spp. e Clostridium spp foi reduzido em 82 e 97% com a aplicação de cal na dosagem de 300g m-2 e 100% na dosagem de 600 e 900g m-2, ambos diferindo significativamente em relação ao controle (antes da aplicação da cal). A atividade de água da cama reduziu progressivamente (de 0,2 a 3,82%)com a utilização de níveis crescentes de cal. Conclui-se que o uso da cal na cama de aviário, mesmo nas doses mais baixas, reduz o número mais provável de Salmonella e Clostridium ssp.


This study aimed to evaluate the efficacy of quicklime (CaO) for reducing Salmonella and Clostridium spp. population in used litter from floor pens of broilers. Four treatments were tested: (T1) control (without quicklime); (T2) 300g quicklime m-2; (T3) 600g quicklime m-2; and (T4) 900g quicklime m-2. The following average pH values were observed 12 days after adding quicklime: 8.95, 9.91, 10.75 and 11.11 for treatments 1, 2, 3 and 4, respectively. An 82 and 97%reduction in the most probable number Log10 (CFU) of Salmonella and Clostridium spp, respectively, was observed when 300g m-2 of quicklime was added to the used litter from floor pens of broilers. Additionally, a 100% reduction was obtained when both 600 and 900g m-2 of quicklime were added,differing significantly from control (before adding quicklime). A progressive reduction in water activity (from 0.2 to 3.82%) was observed when growing levels of quicklime were used. In conclusion, even the lowest level of quicklime added to litter from floor pens of broilers reduces the most probable number of Salmonella and Clostridium spp.


Assuntos
Animais , Óxido de Cálcio , Clostridium , Salmonella , Aves Domésticas
15.
Ciênc. rural ; 39(3): 838-843, maio-jun. 2009. ilus, tab
Artigo em Inglês | LILACS | ID: lil-514091

RESUMO

Deep litter systems represent low cost alternatives to raise growing-finishing pigs, reducing slurry accumulation, although pig's thermal comfort may be negatively affected by the heat produced inside the litter. This study compared environmental and performance parameters for growing-finishing pigs raised on deep litter systems having distinct depths and on solid floor. The experiment was conducted in a region of temperate climate of Brazil, comparing three treatments: litter having rice husk 0.5m (T1); and 0.25m deep (T2); and solid concrete floor (T3). The first litter was used in two lots and replaced by a second litter used in other two lots, during 52 weeks. Each lot included five pigs in a 7m² pen, from 60 to 145 d of age. Environmental parameters were determined at weekly intervals, including: atmospheric temperature; relative humidity; temperature at the center of the pen, in the surface (TSF); and at half of the depth (THD), only for T1 and T2. Feed consumption and weight of pigs were measured every four weeks. Atmospheric temperature and relative humidity were not influenced by the treatments (P>0.05). Mean TSF was 22.8 ± 3.6°C, being lower for T3 (P<0.05), but with no difference between T1 and T2 (P>0.05). TSF was higher for new than for used litters (P<0.001) and for the first than for the second litter (P=0.03), apparently increasing in lots raised during termophilic phases. Mean THD was 33.8±10.8°C, being higher for T1 than for T2 (P<0.05). THD was also higher for new than for used litters (P<0.001) and for the first than for the second litters (P<0.05). No growth performance parameter differed across treatments (P>0.05). Despite the potential unfavorable thermal comfort under high temperatures, deep litter systems can be used to raise pigs in the growing-finishing phases due to the absence of negative effects for growth performance.


O uso de cama representa uma alternativa de baixo custo para a criação de suínos em crescimento e em terminação, promovendo redução do acúmulo de dejetos, embora o conforto térmico dos animais possa ser prejudicado pelo calor produzido no interior da cama. Este estudo compara os parâmetros ambientais e o desempenho de crescimento de suínos em sistemas de criação sobre cama, com profundidades distintas, e sobre piso concreto. O experimento foi realizado em uma região de clima temperado na região Sul do Brasil, comparando três tratamentos: cama de casca de arroz com 0,5m (T1), com 0,25m de profundidade (T2) e piso de concreto (T3). A primeira cama foi usada em dois lotes de animais e foi substituída por uma segunda, usada em outros dois lotes, compreendendo 52 semanas. Cada lote foi constituído por cinco animais criados dos 60 aos 145 dias de idade, em uma baia de 7m². Os seguintes parâmetros ambientais foram medidos semanalmente: temperatura ambiente, umidade relativa e temperatura no centro da baia, na superfície (TSF) e na metade da profundidade da cama (TMP), apenas em T1 e T2. O consumo de ração e o peso dos animais foram aferidos a cada quatro semanas. A temperatura ambiente e a umidade relativa não foram influenciadas pelos tratamentos (P>0,05). A TSF média foi de 22,8±3,6°C, sendo menor no T3 (P<0,05), mas sem diferir entre T1 e T2 (P>0,05). A TSF foi mais alta nas camas novas do que nas usadas (P<0,001) e nas primeiras camas em comparação com as segundas (P=0,03), aparentemente sendo mais alta nos lotes criados durante as fases termofílicas. A TMP média foi de 33,8 ± 10,8°C, sendo mais alta no T1 do que no T2 (P<0,05). A TMP também foi mais alta nas camas novas do que nas usadas (P<0,001) e nas primeiras camas em comparação com as segundas (P<0,05). Nenhum dos parâmetros de crescimento diferiu entre os tratamentos (P<0,05). Ainda que possam ocorrer condições de conforto térmico desfavoráveis aos animais, principalmente ...

16.
Ciênc. rural ; 38(9): 2650-2653, dez. 2008. tab
Artigo em Português | LILACS | ID: lil-498431

RESUMO

Foram avaliados os efeitos da aplicação de Impact P® sobre a cama de aviário de matrizes de corte mediante o monitoramento de parâmetros microbiológicos. O Impact P® é um produto formulado através de Bacillus subtillis e suas enzimas que atuam sobre os dejetos animais e matéria orgânica, utilizando-os como fonte alimentar, visando melhorar as condições da cama dentro de aviários. Na 58ª semana de idade das matrizes foi trocado todo material de cama e então aplicados os seguintes tratamentos: T1- controle; T2 - Impact P® na dosagem de 2,5gm-2 de cama; T3 - Impact P® na dosagem de 5,0g m-2 de cama. Foram realizadas contagens de enterobactérias totais em agar McConkey em amostra de cama nova e após 3, 10, 17, 24 e 31 dias de uso da cama pelas aves e tratamentos com Impact P®. A análise estatística foi realizada no procedimento General Linear Models - GLM que utiliza o método dos quadrados mínimos, em um esquema fatorial 3x4 (tratamento x tempo de uso da cama) em delineamento completamente casualizado, com quatro repetições por tratamento, sendo as médias comparadas pelo teste de Tukey. A dosagem de 5,0g de Impact P® por m² de cama foi eficiente para reduzir em aproximadamente 13% a contagem logarítmica total de enterobactérias em comparação com o grupo não tratado (2,89 versus 3,31log10 (UFC), respectivamente, P<0,05).


This study aimed to evaluate the utilization of Impact P® in used litter from floor pens of broiler breeders through the monitoring of microbiological parameters. Impact P® is a commercial product obtained from Bacillus subtillis and it enzymes. Using animal litter and organic matter as a feed source, the product was designed to improve the quality of floor pens of broiler breeders. When hens aged 58 weeks, all used floor pens material was replaced with a new one and the following treatments were tested: T1 - control; T2 - 2.5g Impact P® m-2 litter; T3- 5.0g Impact P® m-2 litter. Counting of number of enterobacterium colonies in agar Mac-ConcKey was performed in a sample of new floor pens material and after 3, 10, 17, 24 and 31 days of litter treatment with Impact P®. The statistical analysis was accomplished with the General Linear Models - GLM procedure, using the minimum square method in a 3x4 factorial (treatment vs. time of floor pens utilization), in a completely randomized design with four replications. The averages were compared by Tukey test. The utilization of 5.0g Impact P® m-2 litter was efficient to reducing approximately 13% logarithmic total counting of the enterobacterium in comparison to the untreated group (2.89 versus 3.31log10 (CFU), respectively, P<0.05).

17.
Ciênc. rural ; 38(7): 1978-1983, out. 2008. tab
Artigo em Português | LILACS | ID: lil-495111

RESUMO

Este estudo teve por objetivo avaliar o uso da dimetilacetamida (DMA) e de glicerol na criopreservação de sêmen suíno sobre as taxas de concepção e fertilização in vivo, utilizando o método de inseminação artificial pós-cervical. Foram sincronizadas 60 leitoas pré-púberes e inseminadas com o uso de sêmen congelado com glicerol 3 por cento (30 fêmeas) e DMA 5 por cento (30 fêmeas). O método de inseminação utilizado foi o pós-cervical, com concentração de 1 x 10(9) espermatozóides vivos por dose. Após 36 a 40h da inseminação, as fêmeas foram abatidas, sendo realizada a contagem de corpos hemorrágicos (CH) nos ovários. Foi realizada a lavagem dos ovidutos das fêmeas, verificando o número de estruturas recuperadas (oócitos e embriões), calculando-se as taxas de concepção e fertilização. A média de CH nas fêmeas do grupo glicerol 3 por cento não diferiu (P>0,05) daquelas do grupo DMA 5 por cento (10,4 x 10,2, respectivamente). Não houve diferença (P>0,05) nas taxas de recuperação de estruturas entre os grupos glicerol 3 por cento (68,9 por cento) e DMA 5 por cento (66,9 por cento). Os resultados obtidos nos grupos glicerol 3 por cento e DMA 5 por cento para as taxas de concepção (73,3 x 76,6 por cento) e fertilização (48,6 x 59,4 por cento) não apresentaram diferença (P>0,05). Conclui-se que não há diferenças nas taxas de concepção e fertilização in vivo utilizando-se sêmen congelado com o uso de dimetilacetamida ou de glicerol.


The objective of this study was to evaluate the use of dimethylacetamide (DMA) and glycerol in boar semen cryopreservation on the conception and fertility rates.Sixty pre-pubertal gilts were synchronized and inseminated with semen including either glycerol 3 percent or DMA 5 percent as cryoprotectants (n=30 for both groups). Artificial insemination was conducted with the intrauterine method using doses with 1 x 10(9) viable spermatozoa. The gilts were slaughtered 36-40h after the insemination and the hemorrhagic bodies (CH) in the ovaries were counted. The oviducts were washed, so oocytes and embryos could be recovered to determine the conception and fertility rates. The average CH obtained with glycerol 3 percent did not differ (P>0.05) from those observed with DMA (10.4 x 10.2, respectively). Recovery rates also did not differ (P>0.05) between groups (68.9 percent with glycerol and 66.9 percent with DMA). Conception (73.3 x 76.6 percent) and fertility rate (48.6 x 59.4 percent) were also similar (P>0.05) for glycerol and DMA, respectively. Those results indicate that DMA 5 percent can replace glycerol 3 percent in the composition of extenders for frozen boar semen.


Assuntos
Animais , Feminino , Criopreservação/veterinária , Inseminação Artificial/métodos , Inseminação Artificial/veterinária , Sêmen , Suínos , Amidas , Crioprotetores , Glicerol
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