Antibacterial efficacy of commercial disinfectants on dirt floor used in poultry breeder houses

Dirt floors are used on most Brazilian poultry farms since the construction of concrete floors is very expensive. In vitro tests carried out to verify the effectiveness of disinfectants do not consider the adverse conditions found in poultry farms. Therefore, the present study aimed at evaluating the effect of six commercial disinfectants on the reduction of total and fecal coliforms on the dirt floor of breeder houses. The amount of disinfectant solution to be used per square meter was defined by counting total and fecal coliforms at different soil depths and by analyzing soil physical properties. Coliforms were detected at 0.5 cm, and one liter of disinfectant solution was sufficient for soil saturation at this depth. After that, the efficacy of six commercial products (caustic soda, hydrated lime, phenols 1 and 2, iodine, glutaraldehyde, and quaternary ammonium) in reducing the number of coliforms, after six hours of contact with the dirt floor, was assessed using the most probable number (MPN) method. Escherichia coli specimens isolated from the dirt floor were used to evaluate in vitro effectiveness of disinfectants. Products that yielded the best results in the MPN method were also effective in the in vitro tests. Among the tested disinfectants, hydrated lime was the most efficient, reducing the initial contamination by 2.9 log after six hours of contact with the dirt floor

Qualidade do solo em sistemas de produção de hortaliças orgânico e convencional Soil quality in organic and conventional vegetables production systems

Sendo o solo um dos principais pilares de sustentabilidade de todo sistema de produção, a análise integrada dos atributos edafobiológicos pode constituir-se em ferramenta importante para avaliar a qualidade do mesmo. O objetivo do trabalho foi avaliar a qualidade do solo em função das práticas agrícolas adotadas, mediante a análise integrada de atributos físicos, químicos e biológicos. A pesquisa foi realizada em 2006 e 2007 nas microrregiões de Ibiúna e Socorro, no estado de São Paulo, em pequenas propriedades familiares orgânicas e convencionais. Foram avaliados os atributos físicos, químicos e biológicos, mediante coletas de amostras de solos sob cultivo de hortaliças e em solos de mata ou pastagem. O levantamento de dados sobre as práticas agrícolas foi realizado em cada sistema de produção. Os dados obtidos foram submetidos à análise de componentes principais (ACP). A ACP identificou maior grau de similaridade entre os solos sob cultivo em Socorro e suas respectivas testemunhas que os solos de Ibiúna, nitidamente separados em função do seu uso (mata ou cultivo) e indicando melhor manejo dos mesmos em Socorro. De maneira geral, concluiu-se que as práticas agrícolas utilizadas na maioria das propriedades orgânicas e convencionais favoreceram a degradação do solo, devida principalmente ao revolvimento intensivo e à ausência de cobertura do solo. Estes fatores provocaram redução dos teores de matéria orgânica do solo, da biomassa microbiana, da emergência de plântulas e da estabilidade de agregados nas áreas de cultivo em relação às áreas testemunhas.<br>The soil is one of the most important sustainability columns of the production system. The integrated analysis of the edaphobiological attributes can be an important tool for soil quality evaluation. We evaluated the soil quality regarding the adopted agriculture practices, using the integrated analysis of physical, chemical and biological attributes. The research was carried out in Ibiúna and Socorro, São Paulo state, Brazil, in organic and conventional production, on small and family farms. Physical, chemical and biochemical parameters were evaluated during 2006 and 2007 in soils under vegetable cultivation, native forest or fallow, taken as reference of natural soil. Agricultural practices data were collected in each production system. The obtained data were submitted to principal component analysis (PCA). There was no pronounced grouping trend according to the production system, organic or conventional, but there was a grouping according to the soil use (forest/fallow land or cultivation). The PCA identified greater degree of similarity between Socorro's cultivation soil and its respective controls compared to Ibiuna's soil, clearly separated according to its use (forest or cropping), indicating better soil management in Socorro. In general, the results allow to conclude that agricultural practices in most of both organic and conventional production systems, caused soil degradation, due to, mainly, intensive soil tillage and no soil mulching, as indicated by the reduction of soil organic matter, microbial biomass, plant emergence and aggregate stability in cultivated areas relative to control ones