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1.
Dr. Marion D. Kendall 《Cell and tissue research》1978,190(3):459-479
Summary Following the withdrawal of blood from the brachial vein of adult wild starlings (Sturnus vulgaris) changes in the cell populations within the bone marrow and thymus were observed over an eight day period. The packed cell volume, haemoglobin content and reticulocyte count of the peripheral blood was determined before and after haemorrhage.The maximum effect of the haemorrhage was observed in the bone marrow after four days when the population of small lymphocytes, and basophilic erythroid precursors were reduced to less than 1%. At the same time the percentage of another line of erythroid cells increased to 68%. This second erythroid lineage was the major erythroid line in the thymus, and again maximum representation occurred at 4 days post haemorrhage. After this the thymus became predominantly lymphoid and started to increase in size.The two erythroid lines are described and their status with regard to avian thrombocytes is also discussed.The peripheral blood had not attained the pre-haemorrhagic values for reticulocyte counts by eight days although the packed cell volumes and haemoglobin contents were similar.I would like to thank Dr. Peter Ward of the Institute of Terrestrial Ecology for help in obtaining the starlings. Thanks are also due to the staff of the Anatomy Department of St. Thomas's Hospital Medical School, and in particular Mr. Watson. This and other work on the thymus is possible due to the support of the Research (Endowments) Committee of St. Thomas's Hospital 相似文献
2.
PCR-ELISAs for the detection of Campylobacter jejuni and Campylobacter coli in poultry samples 总被引:1,自引:0,他引:1
Grennan B O'Sullivan NA Fallon R Carroll C Smith T Glennon M Maher M 《BioTechniques》2001,30(3):602-6, 608-10
Campylobacter species, primarily Campylobacter jejuni and Campylobacter coli, are regarded as a major cause of human gastrointestinal disease, commonly acquired by eating undercooked chicken. We describe a PCR-ELISA for the detection of Campylobacter species and the discrimination of C. jejuni and C. coli in poultry samples. The PCR assay targets the 16S/23S ribosomal RNA intergenic spacer region of Campylobacter species with DNA oligonucleotide probes designed for the specific detection of C. jejuni, C. coli, and Campylobacter species immobilized on Nucleo-Link wells and hybridized to PCR products modified with a 5' biotin moiety. The limit of detection of the PCR-ELISA was 100-300 fg (40-120 bacterial cells) for C. jejuni and C. coli with their respective species-specific oligonucleotide probes and 10 fg (4 bacterial cells) with the Campylobacter genus-specific probe. Testing of poultry samples, which were presumptive positive for Campylobacter following culture on the Malthus V analyzer, with the PCR-ELISA determined Campylobacter to be present in 100% of samples (n = 40) with mixed cultures of C. jejuni/C. coli in 55%. The PCR-ELISA when combined with culture pre-enrichment is able to detect the presence of Campylobacter and definitively identify C. jejuni and C. coli in culture-enriched poultry meat samples. 相似文献
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T.M. Wassenaar A. Fernández-Astorga R. Alonso V.T. Marteinsson S.H. Magnússon A.B. Kristoffersen M. Hofshagen 《Letters in applied microbiology》2009,49(3):388-395
Aims: The genetic diversity of Campylobacter isolated from human infection and from poultry was assessed in strains originating in three different European regions in order to compare these two hosts and to investigate European regional differences.
Methods and Results: Randomly chosen isolates originated from Norway, Iceland and Basque Country in Spain were genotyped by sequencing of the short variable region (SVR) of flaA . A total of 293 strains were investigated, c . 100 per country with half originated from either host. The results indicate extensive diversity in both hosts and identified differences in the nature and distribution of genotypes between the countries. These differences could in part be related to geographical location, in that Campylobacter genotypes from Iceland and Norway were more similar to each other than either was to Basque Country.
Conclusions: Differences between the countries exceeded the observed differences between human and poultry isolates within a country.
Significance and Impact of the Study: Regional differences are extensive and should not be ignored when comparing genotyping data originating from different international studies. 相似文献
Methods and Results: Randomly chosen isolates originated from Norway, Iceland and Basque Country in Spain were genotyped by sequencing of the short variable region (SVR) of flaA . A total of 293 strains were investigated, c . 100 per country with half originated from either host. The results indicate extensive diversity in both hosts and identified differences in the nature and distribution of genotypes between the countries. These differences could in part be related to geographical location, in that Campylobacter genotypes from Iceland and Norway were more similar to each other than either was to Basque Country.
Conclusions: Differences between the countries exceeded the observed differences between human and poultry isolates within a country.
Significance and Impact of the Study: Regional differences are extensive and should not be ignored when comparing genotyping data originating from different international studies. 相似文献
4.
Approximately 40 samples of animal feces, drinking water, feed, bedding, pine wood shavings, compost, and manure slurry were collected from two animal research farms (one dairy and one poultry) and analyzed for ceftriaxone-resistant bacteria. Our study revealed that the total percentage of aerobic bacteria with reduced susceptibility to ceftriaxone (minimal inhibitory concentration (MIC) > or = 16 micro g/mL) ranged from 0.9% to 10.8% in dairy feces and from 0.05% to 3.93% in chicken feces. The percentages of ceftriaxone-resistant bacteria (MIC > or = 64 micro g/mL) were in the range of 0.01% - 2.3% in dairy feces and 0.01% - 0.79% in chicken feces. Environmental samples contained a wide range of ceftriaxone-resistant bacterial populations. Among those environmental samples, fresh pine wood shavings used as chicken bedding contained the highest percentages (41.5%) of ceftriaxone-resistant bacteria, as determined by a plating method. A total of 105 ceftriaxone-resistant (MIC > or = 128 micro g/mL) bacterial isolates were isolated from the above samples and tested for resistance to nine antibiotics: ampicillin, ceftriaxone, streptomycin, kanamycin, gentamicin, chloramphenicol, tetracycline, ciprofloxacin, and nalidixic acid. The most prevalent resistance pattern (34.3%) among isolates included resistance to all nine antibiotics. Results from this study suggest that ceftriaxone-resistant bacteria exist in farm environments, and the ceftriaxone resistance was frequently associated with resistance to multiple antibiotics. Environmental sources such as pine wood shavings used as bedding can be a potential reservoir for transmitting the multidrug-resistant bacteria. 相似文献
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Rivoal K Ragimbeau C Salvat G Colin P Ermel G 《Applied and environmental microbiology》2005,71(10):6216-6227
In many industrialized countries, the incidence of campylobacteriosis exceeds that of salmonellosis. Campylobacter bacteria are transmitted to humans mainly in food, especially poultry meat products. Total prevention of Campylobacter colonization in broiler flocks is the best way to reduce (or eliminate) the contamination of poultry products. The aim of this study was to establish the sources and routes of contamination of broilers at the farm level. Molecular typing methods (DNA macrorestriction pulsed-field gel electrophoresis and analysis of gene polymorphism by PCR-restriction fragment length polymorphism) were used to characterize isolates collected from seven broiler farms. The relative genomic diversity of Campylobacter coli and Campylobacter jejuni was determined. Analysis of the similarity among 116 defined genotypes was used to determine clusters within the two species. Furthermore, evidence of recombination suggested that there were genomic rearrangements within the Campylobacter populations. Recovery of related clusters from different broiler farms showed that some Campylobacter strains might be specifically adapted to poultry. Analysis of the Campylobacter cluster distribution on three broiler farms showed that soil in the area around the poultry house was a potential source of Campylobacter contamination. The broilers were infected by Campylobacter spp. between days 15 and 36 during rearing, and the type of contamination changed during the rearing period. A study of the effect of sanitary barriers showed that the chickens stayed Campylobacter spp. free until they had access to the open area. They were then rapidly colonized by the Campylobacter strains isolated from the soil. 相似文献
6.
SAMUEL K. SHEPPARD FRANCES M. COLLES NOEL D.
McCARTHY NORVAL J. C. STRACHAN IAIN D. OGDEN KEN J. FORBES JOHN F. DALLAS MARTIN C. J. MAIDEN 《Molecular ecology》2011,20(16):3484-3490
Bacterial populations can display high levels of genetic structuring but the forces that influence this are incompletely understood. Here, by combining modelling approaches with multilocus sequence data for the zoonotic pathogen Campylobacter, we investigated how ecological factors such as niche (host) separation relate to population structure. We analysed seven housekeeping genes from published C. jejuni and C. coli isolate collections from a range of food and wild animal sources as well as abiotic environments. By reconstructing genetic structure and the patterns of ancestry, we quantified C. jejuni host association, inferred ancestral populations, investigated genetic admixture in different hosts and determined the host origin of recombinant C. jejuni alleles found in hybrid C. coli lineages. Phylogenetically distinct C. jejuni lineages were associated with phylogenetically distinct wild birds. However, in the farm environment, phylogenetically distant host animals shared several C. jejuni lineages that could not be segregated according to host origin using these analyses. Furthermore, of the introgressed C. jejuni alleles found in C. coli lineages, 73% were attributed to genotypes associated with food animals. Our results are consistent with an evolutionary scenario where distinct Campylobacter lineages are associated with different host species but the ecological factors that maintain this are different in domestic animals such that phylogenetically distant animals can harbour closely related strains. 相似文献
7.
Colles FM Jones K Harding RM Maiden MC 《Applied and environmental microbiology》2003,69(12):7409-7413
The genetic diversity of Campylobacter jejuni isolates from farm animals and their environment was investigated by multilocus sequence typing (MLST). A total of 30 genotypes, defined by allelic profiles (assigned to sequence types [STs]), were found in 112 C. jejuni isolates originating in poultry, cattle, sheep, starlings, and slurry. All but two of these genotypes belonged to one of nine C. jejuni clonal complexes previously identified in isolates from human disease and retail food samples and one clonal complex previously associated with an environmental source. There was some evidence for the association of certain clonal complexes with particular farm animals: isolates belonging to the ST-45 complex predominated among poultry isolates but were absent among sheep isolates, while isolates belonging to the ST-61 and ST-42 complexes were predominant among sheep isolates but were absent from the poultry isolates. In contrast, ST-21 complex isolates were distributed among the different isolation sources. Comparison with MLST data from 91 human disease isolates showed small but significant genetic differentiation between the farm and human isolates; however, representatives of six clonal complexes were found in both samples. These data demonstrate that MLST and the clonal complex model can be used to identify and compare the genotypes of C. jejuni isolates from farm animals and the environment with those from retail food and human disease. 相似文献
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Olivier Sparagano Aleksandar Pavlićević Takako Murano Antonio Camarda Hamid Sahibi Ole Kilpinen Monique Mul Rick van Emous Sophie le Bouquin Kristian Hoel Maria Assunta Cafiero 《Experimental & applied acarology》2009,48(1-2):3-10
Recent surveys and sample collection have confirmed the endemicity of Dermanyssus gallinae in poultry farming worldwide. The reduction in number and efficacy of many acaricide products has accentuated the prevalence rates of this poultry ectoparasite observed more often in non intensive systems such as free-range, barns or backyards and more often in laying hens than in broiler birds. The lack of knowledge from producers and the utilisation of inadequate, ineffective or illegal chemicals in many countries have been responsible for the increase in infestation rates due to the spread of acaricide resistance. The costs for control methods and treatment are showing the tremendous economic impact of this ectoparasite on poultry meat and egg industries. This paper reviews the prevalence rates of this poultry pest in different countries and for different farming systems and the production parameters which could be linked to this pest proliferation. 相似文献
9.
Study on the epidemiology and control of Campylobacter jejuni in poultry broiler flocks. 总被引:1,自引:0,他引:1
A van de Giessen S I Mazurier W Jacobs-Reitsma W Jansen P Berkers W Ritmeester K Wernars 《Applied and environmental microbiology》1992,58(6):1913-1917
Broiler flocks are frequently infected with Campylobacter jejuni. The origin of the infection is still unclear. The question of whether colonization of flocks results from transmission of C. jejuni from breeder flocks to progeny (vertical transmission) or from environmental sources (horizontal transmission) remains to be answered. Therefore, in this study samples were taken from successive broiler flocks in two broiler houses (house A on farm A and house B1 on farm B) as well as from the environment of the houses. All C. jejuni isolates were typed by using the Penner serotyping system, and part of the isolates from farm B were typed by using a randomly amplified polymorphic DNA-typing system. In poultry house A, C. jejuni was isolated from the first flock but not from subsequent flocks. In poultry house B1, C. jejuni strains of the same Penner serotypes and exhibiting identical DNA profiles were isolated from successive flocks. Infection of the flocks from a common source via horizontal pathways is suspected, while a vertical route of infection is not likely to exist. Application of measures to control horizontal transmission of C. jejuni on farm B was successful. 相似文献
10.
Study on the epidemiology and control of Campylobacter jejuni in poultry broiler flocks. 总被引:1,自引:2,他引:1
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A van de Giessen S I Mazurier W Jacobs-Reitsma W Jansen P Berkers W Ritmeester K Wernars 《Applied microbiology》1992,58(6):1913-1917
Broiler flocks are frequently infected with Campylobacter jejuni. The origin of the infection is still unclear. The question of whether colonization of flocks results from transmission of C. jejuni from breeder flocks to progeny (vertical transmission) or from environmental sources (horizontal transmission) remains to be answered. Therefore, in this study samples were taken from successive broiler flocks in two broiler houses (house A on farm A and house B1 on farm B) as well as from the environment of the houses. All C. jejuni isolates were typed by using the Penner serotyping system, and part of the isolates from farm B were typed by using a randomly amplified polymorphic DNA-typing system. In poultry house A, C. jejuni was isolated from the first flock but not from subsequent flocks. In poultry house B1, C. jejuni strains of the same Penner serotypes and exhibiting identical DNA profiles were isolated from successive flocks. Infection of the flocks from a common source via horizontal pathways is suspected, while a vertical route of infection is not likely to exist. Application of measures to control horizontal transmission of C. jejuni on farm B was successful. 相似文献
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Helmut Kruckenberg Thomas M��ller Conrad Freuling Ralph-Udo M��hle Anja Globig Horst Schirrmeier Melanie Buss Timm Harder Matthias Kramer Kathrin Teske Kees Polderdijk Dieter Wallschl?ger Andreas Hlinak 《European Journal of Wildlife Research》2011,57(5):1025-1032
In order to investigate the potential role of arctic geese in the epidemiology, the spatial and temporal spread of selected avian diseases, in autumn 2002, a virological and serological survey designed as capture-mark-resighting study was conducted in one of the most important coastal resting sites for migratory waterfowl in Germany. Oropharyngeal, cloacal swabs and blood samples were collected from a total of 147 birds comprising of three different arctic geese species including White-fronted Goose (Anser albifrons), Tundra Bean Goose (Anser fabalis rossicus), Pink-footed Goose (Anser brachyrhynchus) as well as from 29 non-migratory Canada Geese (Branta canadensis). Altogether, six adeno-like viruses (ALV; 95% CI, 1.74?C9.92%) and two avian paramyxoviruses (APMV-4; 95% CI, 0.19?C5.53%) were isolated mainly from juvenile White-fronted Geese. In addition, four Canada Geese were infected with lentogenic APMV-1 (95% CI, 3.89?C31.66%) at the date of sampling. No avian influenza viruses, reo-like viruses could be isolated despite serological evidence. Likewise, no evidence of current or previous infection by West Nile virus was found. Of the 147 birds tagged in the following years, 137 birds were re-sighted between 2002 and 2008 accumulating to 1925 sightings. About 90% of all sightings were reported from the main wintering and resting sites in Germany and The Netherlands. Eight of the resighted geese were virus positive (ALV and APMV-4) at the time point of sampling in 2002. 相似文献
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Summary The number of identical S-alleles between two wild populations of B. campestris, one in Turkey, the other in Japan, that have been independent of one another for a long time was investigated. Diallel pollination tests between 38 S-allele homozygotes, i.e., 16 S-allele homozygotes from Turkey and 22 from Japan, revealed that these were 29 different S-alleles only 4 common ones. These S-alleles were differentiated by the iso-electric focusing (IEF) analysis of S-locus glycoproteins (SLGs) stained with an antiserum against SLG8. All identical S-alleles had the major SLG band at the same pI value without exception, even though they were collected from different populations. However, the number of minor bands of SLGs varied between the two populations; the S-alleles in Balcesme had generally fewer minor bands than those in Oguni. The 29 independent S-alleles were numbered from S
21 to S
49 according to the pI value of the major SLG band. The major bands whose pI values were 7.5–8.5 were most common. Blot-hybridization patterns of genomic DNA hybridized with SLG
8 cDNA were not always the same among the strains of identical S-alleles obtained from different populations. Because about 20% of the S-alleles were shared between the two populations, it can be inferred that more than hundreds of S-alleles have been accumulated by mutation in B. campestris throughout the world. 相似文献
15.
Environmental contributions to variation on menarcheal age were studied in 2018 Spanish girls and women from de Province of Cuenca. (Spain). This province has a big variation in altitude and is one of the most representative as middle-altitude population in Spain. Maturation's delay in high populations is well referenced but there are less studies in European middle-altitude populations. To give news about this topic is the main objective of this paper. Retrospective Method was employed in adult sample and Status-Quo in young population (9 to 15 years old) Another social, nutritional, somatic and educational levels was recording to give a variation contest. Our study shows a significantly variation between the provincial areas. In effect, the population of “Sierra”, the mountain region has the last maturation in the adults (13.45±0.73) as well as in girls (13.26±1.07). Secular change was observed in relation with this parameter., but less intense that in total, of province. We can confirm the utility of the age of menarche as evaluator of human variation in time and ecological situations. 相似文献
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McGinnity P Prodöhl P Ferguson A Hynes R Maoiléidigh NO Baker N Cotter D O'Hea B Cooke D Rogan G Taggart J Cross T 《Proceedings. Biological sciences / The Royal Society》2003,270(1532):2443-2450
The high level of escapes from Atlantic salmon farms, up to two million fishes per year in the North Atlantic, has raised concern about the potential impact on wild populations. We report on a two-generation experiment examining the estimated lifetime successes, relative to wild natives, of farm, F(1) and F(2) hybrids and BC(1) backcrosses to wild and farm salmon. Offspring of farm and "hybrids" (i.e. all F(1), F(2) and BC(1) groups) showed reduced survival compared with wild salmon but grew faster as juveniles and displaced wild parr, which as a group were significantly smaller. Where suitable habitat for these emigrant parr is absent, this competition would result in reduced wild smolt production. In the experimental conditions, where emigrants survived downstream, the relative estimated lifetime success ranged from 2% (farm) to 89% (BC(1) wild) of that of wild salmon, indicating additive genetic variation for survival. Wild salmon primarily returned to fresh water after one sea winter (1SW) but farm and 'hybrids' produced proportionately more 2SW salmon. However, lower overall survival means that this would result in reduced recruitment despite increased 2SW fecundity. We thus demonstrate that interaction of farm with wild salmon results in lowered fitness, with repeated escapes causing cumulative fitness depression and potentially an extinction vortex in vulnerable populations. 相似文献
19.
Bayindir Y Bayraktar M Karadag N Ozcan H Kayabas U Otlu B Durmaz R Doganay M 《The new microbiologica》2011,34(1):37-43
Human orf is a viral zoonotic infection caused by Parapoxvirus. The skin lesions of human orf can be misdiagnosed as cutaneous anthrax leading to overtreatment and also fear. This study was conducted to analyze an outbreak which led to deaths among kids and lambs in the same flock, and skin lesions in some persons who were living on the same farm that were initially diagnosed as cutaneous anthrax by a practitioner. Eight patients with skin lesions and eleven persons who had no skin lesion were considered as patients and control groups, respectively. The cultures obtained from the lesions of all patients were negative for Bacillus anthracis. The diagnosis of skin lesions was done by clinical findings, histopathological examination and PCR as human orf. To be under 20 years of age, direct contact with the animals, and contact with flayed skin of sick animals were the risk factors for human orf (Odds Ratio 7.5; 95% Confidence Interval 1.02-54.54, OR 12.25; 95% CI:1.3-100.9, OR 16.67; 95% CI:1.65-148.20, respectively). Orf should be kept in mind in the differential diagnosis of skin lesions resembling anthrax. For control and prevention of orf, transmission routes should be known; good hand hygiene and other personal protective measures have to be implemented. 相似文献
20.
Changes in the carriage of Campylobacter strains by poultry carcasses during processing in abattoirs 总被引:1,自引:0,他引:1
Newell DG Shreeve JE Toszeghy M Domingue G Bull S Humphrey T Mead G 《Applied and environmental microbiology》2001,67(6):2636-2640
The recent development of simple, rapid genotyping techniques for Campylobacter species has enabled investigation of the determinative epidemiology of these organisms in a variety of situations. In this study we have used the technique of fla typing (PCR-restriction fragment length polymorphism analysis of the flaA and flaB genes) to identify the sources of strains contaminating the carcasses of five campylobacter-positive and two campylobacter-negative broiler flocks during abattoir processing. The results confirmed that, in the United Kingdom, individual broiler flocks are colonized by a limited number of subtypes of Campylobacter jejuni or C. coli. In some but not all cases, the same subtypes, isolated from the ceca, contaminated the end product as observed in carcass washes. However, the culture methodology, i.e, use of direct plating or enrichment, affected this subtype distribution. Moreover, the number of isolates analyzed per sample was limited. fla typing also indicated that some campylobacter subtypes survive poultry processing better than others. The extent of resistance to the environmental stresses during processing varied between strains. The more robust subtypes appeared to contaminate the abattoir environment, surviving through carcass chilling, and even carrying over onto subsequent flocks. From these studies it is confirmed that some campylobacter-negative flocks reach the abattoir but the carcasses from such flocks are rapidly contaminated by various campylobacter subtypes during processing. However, only some of these contaminating subtypes appeared to survive processing. The sources of this contamination are not clear, but in both negative flocks, campylobacters of the same subtypes as those recovered from the carcasses were isolated from the crates used to transport the birds. In one case, this crate contamination was shown to be present before the birds were loaded. 相似文献