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11.
Background
Microbiological standards within pork slaughter processing plants in the European Union are currently governed by Commission Regulation (EC) 2073/2005, which describes detailed performance criteria at specific stages of the procedure (following carcass dressing and before chilling) for total viable counts (TVC), Enterobacteriaceae (EB) and Salmonella spp. In this study, 95 carcasses from an Irish pork slaughter plant were sampled by swabbing 100 cm2 of surface at three sites (belly, ham, jowl) to examine the effects of eight processing stages (stunning, bleeding, scalding, singeing, polishing, evisceration, final inspection and chilling) on contamination levels.Results
TVC ranged from approximately 1.7–6.3 log cfu cm2 during sampling. There were significant reductions in TVC for all sites after scalding and singeing (p < 0.05), whilst there was a significant increase in counts after polishing and evisceration (p < 0.05) compared with preceding stages. EB counts indicated hygienic weak points in the examined slaughter plant leading to faecal (cross)-contamination, with elevated counts after stunning, bleeding and evisceration (p < 0.05), compared with final counts after chilling.Conclusions
Although the bacterial numbers reported in this study may reflect specific plant practices and temporal influences, results show that contamination can be introduced at various steps in the process and highlight the importance of monitoring locations other than those required by legislation within the process. Monitoring can be used to establish baseline levels for high-risk stages specific to each plant and to assess the effectiveness of additional interventions. 相似文献12.
Luke A. Roy David Teichert-Coddington Sunni Dahl Benjamin H. Beck Craig A. Shoemaker Gregory N. Whitis 《Journal Of Applied Aquaculture》2020,32(3):193-204
ABSTRACT Shrimp farmers in Alabama who produce the Pacific white shrimp, Litopenaeus vannamei, have recently reported abnormally low survival at harvest. Farmers have hypothesized that this phenomenon may be due to disease, toxic algae, shrimp source, or reduced shrimp robustness in later stages of production. To compare performance of shrimp from different sources, postlarvae were obtained from three different hatcheries and stocked on the same day in on-levee tank systems (TS) on two farms (Farm 1-TS; Farm 2-TS1; Farm 2-TS2). Following 104 days of culture on Farm 2-TS1 and Farm 2-TS2, there were no differences in survival (72.8%–91.2%) or final weight (19.8–24.6 g). At Farm 1-TS following 107 days of culture, there were differences in survival from shrimp sourced from one hatchery (40.5%) compared to the other two hatcheries (61.0%–69.8%). Results demonstrated acceptable growth performance and survival from all hatchery sources. 相似文献
13.
14.
The Effects of Mepivacaine Hydrochloride on Antimicrobial Activity and Mechanical Nociceptive Threshold During Amikacin Sulfate Regional Limb Perfusion in the Horse 下载免费PDF全文
15.
Luke Randall Katharina Heinrich Robert Horton Lucy Brunton Matthew Sharman Victoria Bailey-Horne Meenaxi Sharma Ian McLaren Nick Coldham Chris Teale Jeff Jones 《Research in veterinary science》2014
Waste milk samples from 103 farms in England and Wales were examined for the presence of β-lactam antibiotics and ESBL-producing Enterobacteriaceae. Approximately 10 months after the initial sampling, further waste milk, environmental and faecal samples from farms shown to be positive for CTX-M Escherichia coli were investigated further. Isolates with an ESBL phenotype were tested by PCR for the presence of blaCTX-M, blaOXA, blaSHV and blaTEM genes. Isolates positive for blaCTX-M were sequenced to determine CTX-M type. Representative isolates were further examined by PFGE, plasmid replicon typing and serotyping. Of particular interest, 21.4% of waste milk samples contained residues of the cephalosporin cefquinome, which was significantly associated with CTX-M bacteria. Such bacteria occurred in 5.8% of the waste milk samples (including 3.9% CTX-M E. coli). CTX-M types identified were 1, 14, 14b and 15, but none of the E. coli were serotype O25, the serotype of the human pandemic strain. 相似文献
16.
Haitham Sayed Hamed Kayyal Luke Ramsey Salvatore Ceccarelli Michael Baum 《Euphytica》2002,125(2):265-272
A total of 147 simple sequence repeat (SSR) markers (including86 barley and 61 wheat microsatellite markers) were tested for
their segregation in a doubled haploid (DH) and an F2 population of barley. The DH population consisted of 71 doubled haploid lines, developed from F1 plants of a cross between Tadmor and WI2291using isolated microspore culture technique. A genetic linkage map consisting
of 43 microsatellite markers was constructed using the DH population. Particularly on chromosome 4H microsatellite markers
showed distorted segregation ratios. Segregation of DH lines based on molecular markers were compared with segregation of
92 F2 lines from the same cross. The proportion of loci deviating from the expected monogenic segregation ratios in the DH population
was significantly higher (19/43loci, 44%) than in the F2 population (7/43 loci, 16%). The deviation was biased towards the WI2291 parent alleles. In line with this observation, WI2291
was found to perform better than Tadmor in regenerating green plantlets with the isolated microspore-culture technique.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
17.
An experiment to examine the effect of streptobacillary arthritis on mouse populations was conducted in maturing sorghum crops
in mouse-proofed pens. There were three treatment pens and three control pens in which mice with and without clinical signs
of streptobacillary arthritis were introduced, respectively. A constant mouse density (533 mice ha−1) was introduced to the pens by releasing 12 mice in each pen. The sex ratio of introduced mice was also constant by releasing
in each pen nine males and three females. Mean track index was lower in treatment pens than in control pens, indicating that
streptobacillary arthritis reduced the activity of mice. However, this was not translated into a reduction in other population
responses. Mean mouse density at harvest, percentage of female pregnant at harvest, yield loss caused by mice and a feeding
index (oil card index) did not differ significantly between treatment and control groups. A plausible explanation for these
findings was that mice with the clinical signs might be less active but were able to consume as much grains as mice without
the clinical signs because food was in abundant supply. 相似文献
18.
Luke K. Craven 《Asia Pacific viewpoint》2015,56(2):223-236
Migration is increasingly being promoted as a possible adaptive response to risks associated with climate change and other stresses. While migration may present an adaptation pathway in certain contexts, existing research fails to consider the ways in which migration could contribute to vulnerability in sending communities. This paper examines the impact of migration‐affected change on local vulnerability in Lamen Bay, Vanuatu. Qualitative methods, including interviews and focus groups with 58 individuals, were used to determine how migration interacts with the multiple stressors faced by the community. The results show that migration is likely to contribute to vulnerability in already vulnerable communities. In Lamen Bay, migration affects a number of contextual factors that influence exposure and the capacity to respond to change, including labour supply, food security, migrant attitudes, underdevelopment and institutional viability. These results suggest that development policy in Vanuatu needs to address existing vulnerabilities while offering the opportunity to migrate. 相似文献
19.
Low-intensity fires were important for maintaining the structure of Eastern deciduous forests (EDFs) for thousands of years before European settlement of North America, though fire suppression became a standard management practice in the 1930s. More recently, prescribed fires have been reintroduced to EDF habitats to aid in the restoration of native plant diversity, but invasions of non-native species such as Microstegium vimineum (Japanese stiltgrass) may increase prescribed fire intensity and suppress colonization of native species. As fire becomes a more common management tool in these habitats, it is vital to predict fire temperature effects on the native and non-native species present in the system. In this study, we found that prescribed fires in areas invaded by Microstegium can be 250-300 °C hotter than fires in nearby native-dominated areas. We then compared the effects of fire on germination rates of six native and three non-native EDF understory species representing the range of functional groups common in this habitat. We manipulated both fire intensity (temperature and length of exposure) and type of fire effect (direct flame and indirect furnace heat) to generate germination curves and make predictions about potential prescribed fire effects on populations of these species. There were very different responses among species to both direct (flame) and indirect (furnace) heating. Germination of three native species, Lycopus americana (American water horehound), Verbesina alternifolia (wingstem), and Vernonia gigantea (tall ironweed), showed signs of being stimulated by heating at low temperatures, while germination of all non-native species (M. vimineum, Elaeagnus umbellata, and Schedonorus phoenix) were inhibited at these lower intensities. High fire intensity (temperatures above 300 °C) effectively killed most species, though one native species, Senna hebacarpa (American senna) and one non-native species, E. umbellata (autumn olive), were capable of tolerating 500 °C temperatures. We conclude that high-intensity prescribed fires in habitats invaded by Microstegium may reduce seed germination of some non-native species, but may also inhibit the regeneration of native understory species. 相似文献
20.
B G Luke J C Richards 《Journal of the Association of Official Analytical Chemists》1984,67(5):902-904
This paper describes the isolation of 5 organophosphorus residues in beef fat by a commercial sweep co-distillation unit (Unitrex). The operating conditions specified 223 degrees C and nitrogen flow at 230 mL/min. Recoveries of chlorpyriphos, monodechlorchlorpyriphos, bromophos-ethyl, debromobromophos-ethyl, and ethion ranged from 84 to 99%, with coefficients of variation between 3 and 5%. 相似文献