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1.

Background  

Following increased rates of human campylobacteriosis in the late 1990's, and their apparent association with increased consumption of fresh chicken meat, a longitudinal study was conducted in Iceland to identify the means to decrease the frequency of broiler flock colonization with Campylobacter. Our objective in this study was to identify risk factors for flock colonization acting at the broiler farm level.  相似文献   

2.

Background  

Costs and benefits of two Salmonella control policies for broiler production were described and compared. The control options were the Zoonosis Directive 92/117/EC and the more intense strategy, the Finnish Salmonella Control Programme (FSCP).  相似文献   

3.

Background  

Salmonellosis may be a food safety problem when raw food products are mishandled and not fully cooked. In previous work, we developed bioluminescent Salmonella enterica serotypes using a plasmid-based reporting system that can be used for real-time monitoring of the pathogen's growth on food products in short term studies. In this study, we report the use of a Tn7-based transposon system for subcloning of luxCDABE genes into the chromosome of eleven Salmonella enterica serotypes isolated from the broiler production continuum.  相似文献   

4.

Background  

Campylobacter is the most commonly reported bacterial cause of enteritis in humans in the EU Member States and other industrialized countries. One significant source of infection is broilers and consumption of undercooked broiler meat. Campylobacter jejuni is the Campylobacter sp. predominantly found in infected humans and colonized broilers. Sequence analysis of the 16S rRNA gene is very useful for identification of bacteria to genus and species level. The objectives in this study were to determine the degree of intraspecific variation in the 16S rRNA genes of C. jejuni and C. coli and to determine whether the 16S rRNA sequence types correlated with genotypes generated by PFGE analysis of Sma I restricted genomic DNA of the strains.  相似文献   

5.

Background  

The ionophoric coccidiostat salinomycin is widely used in chicken feed. In the near future the use of ionophore coccidiostats may be banned as has been the case for other antimicrobial growth promoters. This study was conducted to examine the effect of salinomycin on Campylobacter jejuni infection and on the composition of the caecal microflora in broiler chickens.  相似文献   

6.

Aim

To examine the inhibition effects of rhizosphere fungal strain MF‐91 on the rice blast pathogen Magnaporthe grisea and sheath blight pathogen Rhizoctonia solani.

Methods and Results

Rhizosphere fungal strain MF‐91 and its metabolites suppressed the in vitro mycelial growth of R. solani. The inhibitory effect of the metabolites was affected by incubation temperature, lighting time, initial pH and incubation time of rhizosphere fungal strain MF‐91. The in vitro mycelial growth of M. grisea was insignificantly inhibited by rhizosphere fungal strain MF‐91 and its metabolites. The metabolites of rhizosphere fungal strain MF‐91 significantly inhibited the conidial germination and appressorium formation of M. grisea. Moreover, the metabolites reduced the disease index of rice sheath blight by 35·02% in a greenhouse and 57·81% in a field as well as reduced the disease index of rice blast by 66·07% in a field. Rhizosphere fungal strain MF‐91 was identified as Chaetomium aureum based on the morphological observation, the analysis of 18S ribosomal DNA internal transcribed spacer sequence and its physiological characteristics, such as the optimal medium, temperature and initial pH for mycelial growth and sporulation production.

Conclusions

Rhizosphere fungus C. aureum is effective in the biocontrolling of rice blast pathogen M. grisea and sheath blight pathogen R. solani both in in vitro and in vivo conditions.

Significance and Impact of the Study

This study is the first to show that rhizosphere fungus C. aureum is a potential fungicide against rice blast and sheath blight pathogens.  相似文献   

7.

Background  

European starlings (Sturnus vulgaris) are an invasive bird species known to cause damage to plant and animal agriculture. New evidence suggests starlings may also contribute to the maintenance and spread of diseases within livestock facilities. Identifying and mitigating the risk pathways that contribute to disease in livestock is necessary to reduce production losses and contamination of human food products. To better understand the impact starlings have on disease transmission to cattle we assessed the efficacy of starling control as a tool to reduce Salmonella enterica within a concentrated animal feeding operation. We matched a large facility, slated for operational control using DRC-1339 (3-chloro-4-methylaniline hydrochloride, also 3-chloro p-toluidine hydrochloride, 3-chloro-4-methylaniline), with a comparable reference facility that was not controlling birds. In both facilities, we sampled cattle feed, cattle water and cattle feces for S. enterica before and after starling control operations.  相似文献   

8.

Background  

The bananaquit (Coereba flaveola) is a small nectivorous and frugivorous emberizine bird (order Passeriformes) that is an abundant resident throughout the Caribbean region. We used multi-gene analyses to investigate the evolutionary history of this species throughout its distribution in the West Indies and in South and Middle America. We sequenced six mitochondrial genes (3744 base pairs) and three nuclear genes (2049 base pairs) for forty-four bananaquits and three outgroup species. We infer the ancestral area of the present-day bananaquit populations, report on the species' phylogenetic, biogeographic and evolutionary history, and propose scenarios for its diversification and range expansion.  相似文献   

9.

Background  

The apparent rediscovery of the Ivory-billed Woodpecker Campephilus principalis in Arkansas, USA, previously feared extinct, was supported by video evidence of a single bird in flight (Fitzpatrick et al, Science 2005, 308:1460–1462). Plumage patterns and wingbeat frequency of the putative Ivory-billed Woodpecker were said to be incompatible with the only possible confusion species native to the area, the Pileated Woodpecker Dryocopus pileatus.  相似文献   

10.

Background  

The subtropical island of Taiwan is an area of high endemism and a complex topographic environment. Phylogeographic studies indicate that vicariance caused by Taiwan's mountains has subdivided many taxa into genetic phylogroups. We used mitochondrial DNA sequences and nuclear microsatellites to test whether the evolutionary history of an endemic montane bird, Steere's Liocichla (Liocichla steerii), fit the general vicariant paradigm for a montane organism.  相似文献   

11.
12.

Aims

To determine the herd prevalence of Enterobacteriaceae producing CTX‐M‐type extended‐spectrum β‐lactamases (ESBLs) among 381 dairy farms in Japan.

Methods and Results

Between 2007 and 2009, we screened 897 faecal samples using BTB lactose agar plates containing cefotaxime (2 μg ml?1). Positive isolates were tested using ESBL confirmatory tests, PCR and sequencing for CTX‐M, AmpC, TEM and SHV. The incidence of Enterobacteriaceae producing CTX‐M‐15 (= 7), CTX‐M‐2 (= 12), CTX‐M‐14 (= 3), CMY‐2 (= 2) or CTX‐M‐15/2/14 and CMY‐2 (= 4) in bovine faeces was 28/897 (3·1%) faecal samples. These genes had spread to Escherichia coli (= 23) and three genera of Enterobacteriaceae (= 5). Herd prevalence was found to be 20/381 (5·2%) dairy farms. The 23 E. coli isolates showed clonal diversity, as assessed by multilocus sequence typing and pulsed‐field gel electrophoresis. The pandemic E. coli strain ST131 producing CTX‐M‐15 or CTX‐M‐27 was not detected.

Conclusions

Three clusters of CTX‐M (CTX‐M‐15, CTX‐M‐2, CTX‐M‐14) had spread among Japanese dairy farms.

Significance and Impact of the Study

This is the first report on the prevalence of multidrug‐resistant CTX‐M‐15–producing E. coli among Japanese dairy farms.  相似文献   

13.

Aim

Ecological restoration is critical for recovering biodiversity and ecosystem services, yet designing interventions to achieve particular outcomes remains fraught with challenges. In the extensive regions where non‐native species are firmly established, it is unlikely that historical conditions can be fully reinstated. To what degree, and how rapidly, can human‐dominated areas be shifted via restoration into regimes that benefit target species, communities or processes?

Location

We explore this question in a >20‐year‐old reforestation effort underway at Hakalau Forest National Wildlife Refuge in montane Hawaii. This large‐scale planting of Acacia koa trees is designed to secure populations of globally threatened bird species by transitioning the site rapidly from pasture to native forest.

Methods

We surveyed all forest birds in multiple corridors of young planted trees, remnant corridors of mature trees along gulches and at sites within mature forest. Using a Bayesian hierarchical approach, we identified which factors (distance from forest, habitat type and surrounding tree cover) had the most important influence on native and exotic bird abundance in the reforestation area.

Results

We found that 90% of native and exotic bird species responded quickly, occupying corridors of native trees approximately a decade after planting. However, native and exotic forest birds responded to markedly different characteristics of the reforested area. Native bird abundance was strongly predicted by proximity to mature forest and remnant corridors; conversely, exotic bird abundance was best predicted by overall tree cover throughout the area reforested.

Main conclusions

Our results demonstrate that large‐scale tree planting in corridors adjacent to mature forest can catalyse rapid recovery (both increased abundance and expanded distribution) of forest birds and that it is possible to design reforestation to benefit native species in novel ecosystems.
  相似文献   

14.

Background  

Unlike northern Europe and most of northern North America, the Eastern Palearctic and the northwesternmost tip of North America are believed to have been almost unglaciated during the Quarternary glacial periods. This could have facilitated long-term survival of many organisms in that area. To evaluate this, we studied the phylogeography in east Asia and Alaska of a boreal migratory passerine bird, the Arctic Warbler Phylloscopus borealis, and compared our results with published data on especially North American species.  相似文献   

15.
Aims: The aim of the study was to investigate the flock prevalence of Campylobacter jejuni and Campylobacter coli in broiler farms in Lithuania and to identify possible persistent strains of Camp. jejuni using amplified fragment length polymorphism (AFLP) typing method. Methods and Results: During 1 year, 42 broiler flocks from 9 broiler farms were examined to determine the prevalence of Campylobacter‐positive broiler flocks in Lithuania. Among 42 broiler flocks examined, 31 flocks (73·8%) were positive for Camp. jejuni and 17 flocks (40·48%) for Camp. coli. Campylobacter jejuni isolates were genotyped by AFLP method using BspDI and BglII restriction enzymes. Typing of 190 isolates generated 50 AFLP genotypes with the highest diversity of strains found in the summer season. Each farm showed one or more predominant AFLP types, and one AFLP type (A32) was found in five broiler farms over a 1‐year period. Conclusions: Campylobacter jejuni and Camp. coli are highly prevalent in broiler farms in Lithuania. Farm‐specific genotypes were identified in all farms examined. Type A32 was present and persisted in different broiler farms, and a common source of transmission of Camp. jejuni was suspected. Significance and Impact of the Study: For the first time, Camp. jejuni in broiler flocks has been genetically characterized in Lithuania. Persistent strains of Camp. jejuni were detected over one period at the beginning of broiler meat production chain and, therefore, the identification of contamination source of such strains and the mechanism of their particular ability to persist are crucial to establish effective control measures against Camp. jejuni infection in broiler farms.  相似文献   

16.

Aims

To confirm the stress‐relieving effects of heat‐inactivated, enteric‐colonizing Lactobacillus gasseri CP2305 (paraprobiotic CP2305) in medical students taking a cadaver dissection course.

Methods and Results

Healthy students (21 males and 11 females) took paraprobiotic CP2305 daily for 5 weeks during a cadaver dissection course. The General Health Questionnaire and the Pittsburgh Sleep Quality Index were employed to assess stress‐related somatic symptoms and sleep quality respectively. The aggravation of stress‐associated somatic symptoms was observed in female students (P = 0·029). Sleep quality was improved in the paraprobiotic CP2305 group (= 0·038), particularly in men (= 0·004). Among men, paraprobiotic CP2305 shortened sleep latency (= 0·035) and increased sleep duration (= 0·048). Diarrhoea‐like symptoms were also effectively controlled with CP2305 (= 0·005) in men. Thus, we observed sex‐related differences in the effects of paraprobiotic CP2305. In addition, CP2305 affected the growth of faecal Bacteroides vulgatus and Dorea longicatena, which are involved in intestinal inflammation.

Conclusions

CP2305 is a potential paraprobiotic that regulates stress responses, and its beneficial effects may depend on specific cell component(s).

Significance and Impact of the Study

This study characterizes the effects of a stress‐relieving para‐psychobiotic in humans.  相似文献   

17.

Background  

Prox1, the vertebrate homolog of prospero in Drosophila melanogaster, is a divergent homeogene that regulates cell proliferation, fate determination and differentiation during vertebrate embryonic development.  相似文献   

18.

Background  

The trade-off between current and future parental investment is often different between males and females. This difference may lead to sexual conflict between parents over care provisioning in animals that breed with multiple mates. One of the most obvious manifestations of sexual conflict over care is offspring desertion whereby one parent deserts the young to increase its reproductive success at the expense of its mate. Offspring desertion is a wide-spread behavior, and its frequency often varies within populations. We studied the consistency of offspring desertion in a small passerine bird, the Eurasian penduline tit Remiz pendulinus, that has an extremely variable breeding system. Both males and females are sequentially polygamous, and a single parent (either the male or the female) incubates the eggs and rears the young. About 28–40% of offspring are abandoned by both parents, and these offspring perish. Here we investigate whether the variation in offspring desertion in a population emerges either by each individual behaving consistently between different broods, or it is driven by the environment.  相似文献   

19.

Background

Hyperemesis gravidarum remains a common, distressing, and significant yet poorly understood disorder during pregnancy. The association between maternal Helicobacter pylori (H. pylori) infection and hyperemesis gravidarum has been increasingly recognized and investigated. This study thus aimed to provide an updated review and meta‐analysis of the topic.

Methods

Using the search terms (H. pyloriOR Helicobacter ORHelicobacter pyloriOR infection) AND (pregnancy OR emesis OR hyperemesis gravidarum OR nausea OR vomiting), a preliminary search on the PubMed, Ovid, Web of Science, Google Scholar, and WanFang database yielded 372 papers published in English between January 1st, 1960 and June 1st, 2017.

Results

A total of 38 cross‐sectional and case‐control studies, with a total of 10 289 patients were eligible for review. Meta‐analysis revealed a significant association between H. pylori infection and hyperemesis gravidarum during pregnancy, with a pooled odds ratio of 1.348 (95% CI: 1.156‐1.539, P < .001). Subgroup analysis found that serologic and stool antigen tests were comparable methods of detecting H. pylori as they yielded similar odds ratios.

Limitations

Although the studies did not have high heterogeneity (I2 = 28%), publication bias was observed, and interstudy discrepancies in the diagnostic criteria adopted for hyperemesis gravidarum limit the reliability of findings. Also, 15 of the included studies were from the same country (Turkey), which could limit the generalizability of current findings. The prevalence of H. pylori infection varies throughout the world, and there may also be pathogenic differences as most strains of H. pylori in East Asia carry the cytotoxin‐associated gene A gene.

Conclusion

H. pylori infection was associated with an increased likelihood of hyperemesis gravidarum during pregnancy. Given the high prevalence of H. pylori infections worldwide, detecting H. pylori infection and the eradication of maternal H. pylori infection could be part of maternal hyperemesis gravidarum management. Further confirmation with robust longitudinal studies and mechanistic investigations are needed.  相似文献   

20.

Background

Burdock complex (BC) constitutes of burdock (Arctium lappa), angelica (Angelica sinensis), gromwell (Lithospermum erythrorhizon), and sesame (Sesamum indicum) oil, which are commonly used in traditional Chinese medicine (TCM) for treating various disorders. This study intended to examine the anti‐H. pylori activity of BC on AGS cell model as well as in asymptomatic H. pylori‐infected subjects.

Materials and Methods

AGS cell incubated with H. pylori and treated with BC to evaluate the minimum inhibition concentration (MIC), cell viability (MTT) anti‐adhesion activity, and inflammatory markers. In case of clinical trial, H. pylori‐positive subjects (urea breath test [UBT] >10%, n = 36) were enrolled and requested to intake BC (n = 19) or placebo (n = 17) for 8 weeks. Antioxidant capacity, total phenol, UBT, inflammatory markers were analyzed at the initial, 4th, 8th, and 10th weeks. Moreover, the endoscopic examination was carried out on baseline and 10th week.

Results

In vitro studies showed that BC treatment significantly inhibited (< .05) the inflammatory markers and adhesion of H. pylori to AGS cell. However, H. pylori‐infected subject ingested with BC for 8 weeks significantly decreased (< .05) the UBT value, inflammatory markers with improved antioxidant activity, and phenolic levels as compared to placebo. Also, consumption of BC considerably healed the ulcer wound.

Conclusion

Overall, the BC could attenuate H. pylori infection by inhibiting H. pylori adhesion and subsequent inflammatory response on the gastric epithelial cell (AGS) as well as clinically ameliorated UBT, antioxidant capacity, and alleviated inflammation to display its anti‐H. pylori activity.  相似文献   

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