Pitfall traps baited with cattle dung are commonly used to characterize local assemblages of coprophilous insects. Baits can be made fresh or be prepared in advance and kept frozen until needed. Insect recoveries are expected to decline with the age of the bait and may be affected by the use of fresh vs.
View Article and Find Full Text PDFPreharvest contamination with bacteria borne by irrigation water may result in leafy vegetables serving as vehicles for transmission of Shiga toxin-producing (STEC) to humans. The influence of starvation-associated stress on the behavior of non-toxin-producing strains of serotype O157:H7 and serotypes O26, O103, O111, and O145 was examined subsequent to their introduction to the phyllosphere of field-grown romaine lettuce as inocula simulating starved (96 h in sterile deionized water) and nutrient-depleted (24 h broth culture) cells. As with O157:H7, leaf populations of the non-O157 strains declined rapidly during the first 72 h postinoculation, displaying the biphasic decay curve typical of serotype O157:H7 isolates.
View Article and Find Full Text PDFUnlabelled: Rapid methods to detect bacterial pathogens on food and strategies to control them are needed to mitigate consumer risk. This study assessed volatile emissions from whole cantaloupe melons (Cucumis melo) as an indicator of Listeria contamination and in response to steam vapor decontamination. Cantaloupe were inoculated with Listeria innocua, a nonpathogenic surrogate for L.
View Article and Find Full Text PDFUnlabelled: Recent bacterial illnesses and outbreaks associated with the consumption of fresh and fresh-cut fruit and vegetables emphasize the need to supply produce that is microbiologically safe while retaining its quality and nutrient value. We assessed the capacity of aerated steam to reduce initial levels and control the posttreatment proliferation of a 4-strain mixture of Listeria innocua, a surrogate for L. monocytogenes, and microflora native to the rind of whole cantaloupes.
View Article and Find Full Text PDFThe influence of liquid dairy manure (LDM) application rates (12.5 and 25 kL ha) and soil type on the decay rates of library-independent fecal source tracking markers (host-associated and mitochondrial DNA) and persistent (>58 d) population structure was examined in a field study. The soils compared were an Aquic Haplorthod and a Typic Haplorthod in Nova Scotia, Canada, that differed according to landscape position and soil moisture regime.
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