Hatchery hygiene evaluation by microbiological examination of hatchery samples
ABSTRACT This study was conducted to investigate the bacterial contamination of air and the surface of equipment and facilities in hatchery. In addition, the inhibitory effects of formaldehyde application methods on aerosol bacterial counts in the hatchers were also investigated. In the operating hatchers, the contamination of air by aerobic bacteria, coliform, and fungi was high, measuring over 300 cfu/63.6 cm(2). In the egg sorting room, contamination was moderate, whereas in the remaining sampling sites such as the setter room, candling-transfer room, and chick counting room, contamination was minimal, measuring less than 10 cfu/63.6 cm(2) for aerobic bacteria, 5 cfu/63.6 cm(2) for coliform, and 2 cfu/63.6 cm(2) for fungi. The bacterial contamination on the surface of the equipment and facilities showed similar tendencies with that of air. However, on the surfaces of the equipment and facilities in the hatcher room corridors and nonoperating hatchers where the bacterial contamination of the air was low, bacterial counts were high, measuring over 100 cfu/16 cm(2). Salmonella was mainly isolated from the hatcher rooms, chick counting room, and the related equipment and facilities but not from the areas used for the earlier processing step such as the egg receiving room, egg sorting room, setter rooms, and candling-transfer room. The Salmonella serotype that was most frequently isolated from the hatchery was Salmonella Senftenberg. The other occasional Salmonella serotypes such as Salmonella Schwarzengrund, Salmonella Madelia, Salmonella Montevideo, and Salmonella Enteritidis were isolated. The experimental group receiving formaldehyde by constant rate infusion during hatching had a significantly superior inhibitory effect on aerosol bacterial count 4 h before hatching as compared with the group receiving formaldehyde into a basin and the negative control group (P < 0.05).
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ABSTRACT: The inherent parallelism of artificial neural networks (ANNs) introduces several difficulties for its software implementation because of the sequential nature of von Neumann architectures. In contrast, hardware implementations offer the possibility to explore the massive parallelism implicit in this model. Also, due to the dynamic nature of ANN's synapses, a flexible hardware platform is required for obtaining efficient solutions. Implementations of ANNs in FPGAs overcome the lack of flexibility of ASICs, and are the most adequate technology for this task. One important question in this field is how to quickly and efficiently evaluate several alternative implementations taking into account the area and timing restrictions of the circuit. This paper presents a flexible high level description and synthesis tool called VANNGen, which allows the designer to explore different hardware implementations of ANNs. In addition, the user can generate synthesizable VHDL code for the Xilinx and Altera FPGA devicesReconfigurable Computing and FPGAs, 2005. ReConFig 2005. International Conference on; 10/2005
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ABSTRACT: In this study, single-walled carbon nanotube (SWNT) filters were prepared using mixed cellulose ester (MCE) filters and carbon nanotubes with three levels of loading: 0.02, 0.16 and 0.64mg/cm2. Both MCE and SWNT filters were used to collect bacterial and fungal aerosols with a total volume of 200L air sampled in indoor and outdoor environments. After sampling, the filters were directly placed on agar plates at 26°C for culturing. The culturable aerosol counts were manually obtained both for MCE and SWNT filters, and the resulting bacterial colony forming units (CFUs) were washed off and subjected to the culturable bioaerosol diversity analysis using polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE). For fungal CFUs, microscopy method was used to study the diversity obtained using different filter types.The results showed that use of SWNT filters with medium and high CNT loadings resulted in significant reduction (up to 2 logs) of culturable bacterial and fungal aerosol counts compared to MCE filters in both environments. For low CNT loading (0.02mg/cm2), very limited inactivation effects were observed for fungal aerosols, while more bacterial counts were obtained possibly due to increased sampling efficiency. PCR-DGGE analysis revealed that SWNT filters at high CNT loading (0.64mg/cm2) resulted in lowest culturable bioaerosol diversity, especially pronounced for outdoor bacterial aerosols. For low and medium CNT loading, the culturable bacterial aerosol diversity remained similar. Fungal aerosol analysis showed that the use of SWNT filters with medium to high CNT loading also resulted in significant reduction of fungal species diversity. The results here demonstrated great promise of the SWNT hybrid filter in controlling biological aerosols, and suggested its potential to impact current air conditioning system.Journal of Aerosol Science 06/2011; 42(6):387-396. DOI:10.1016/j.jaerosci.2011.03.003 · 2.71 Impact Factor