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1.
Antimicrobial‐resistant bacteria represent an important concern impacting both veterinary medicine and public health. The rising prevalence of extended‐spectrum beta‐lactamase (ESBL), AmpC beta‐lactamase, carbapenemase (CRE) and fluoroquinolone‐resistant Enterobacteriaceae continually decreases the efficiency of clinically important antibiotics. Moreover, the potential for zoonotic transmission of antibiotic‐resistant enteric bacteria increases the risk to public health. Our objective was to estimate the prevalence of specific antibiotic‐resistant bacteria on human contact surfaces in various animal environments. Environmental surface samples were collected from companion animal shelters, private equine facilities, dairy farms, livestock auction markets and livestock areas of county fairs using electrostatic cloths. Samples were screened for Enterobacteriaceae expressing AmpC, ESBL, CRE or fluoroquinolone resistance using selective media. Livestock auction markets and county fairs had higher levels of bacteria expressing both cephalosporin and fluoroquinolone resistance than did equine, dairy, and companion animal environments. Equine facilities harboured more bacteria expressing cephalosporin resistance than companion animal shelters, but less fluoroquinolone resistance. The regular use of extended‐spectrum cephalosporins in livestock populations could account for the increased levels of cephalosporin resistance in livestock environments compared to companion animal and equine facilities. Human surfaces, as well as shared human and animal surfaces, were contaminated with resistant bacteria regardless of species environment. Detecting these bacteria on common human contact surfaces suggests that the environment can serve as a reservoir for the zoonotic transmission of antibiotic‐resistant bacteria and resistance genes. Identifying interventions to lower the prevalence of antibiotic‐resistant bacteria in animal environments will protect both animal and public health.  相似文献   

2.
The occurrence of multidrug‐resistant zoonotic bacteria in animals has been increasing worldwide. Working in close contact with livestock increases the risk of carriage of these bacteria. We investigated the occurrence of extended‐spectrum beta‐lactamase (ESBL) and plasmidic AmpC beta‐lactamase producing Enterobacteriaceae (ESBL/pAmpC‐PE) and livestock‐associated methicillin‐resistant Staphylococcus aureus (LA‐MRSA) in Finnish veterinarians (n = 320). In addition to microbiological samples, background information was collected. Bacterial whole genome sequencing was performed to deduce sequence types (STs), spa types and resistance genes of the isolates. In total, 3.0% (9/297) of the veterinarians carried ESBL producing Escherichia coli, with one ESBL producing E. coli isolate producing also AmpC. Seven different STs, sequences of several different plasmid groups as well as several different blaESBL/pAmpC genes existed in different combinations. No carbapenemase or colistin resistance genes were detected. MRSA was detected in 0.3% (1/320) of the samples. The strain belonged to LA‐MRSA clonal complex (CC) 398 (ST398, spa type 011, lacking Panton‐Valentine leukocidin genes). In conclusion, this study shows low carriage of multidrug‐resistant zoonotic bacteria in Finnish veterinarians. However, finding LA‐MRSA for the first time in a sample from a veterinarian in a country with prudent use of animal antimicrobials and regarding the recent rise of LA‐MRSA on Finnish pig farms, a strong recommendation to protect people working in close contact with animals carrying LA‐MRSA CC398 is given. Further studies are needed to explain why the prevalence of LA‐MRSA in veterinarians is lower in Finland than in other European countries.  相似文献   

3.
Antibiotic resistance mediated by bacterial production of extended‐spectrum beta‐lactamase (ESBL) is a global threat to public health. ESBL resistance is most commonly hospital‐acquired; however, infections acquired outside of hospital settings have raised concerns over the role of livestock and wildlife in the zoonotic spread of ESBL‐producing bacteria. Only limited data are available on the circulation of ESBL‐producing bacteria in animals. Here, we report ESBL‐producing Escherichia coli in wild common vampire bats Desmodus rotundus and livestock near Lima, Peru. Molecular analyses revealed that most of this resistance resulted from the expression of blaCTX‐M‐15 genes carried by plasmids, which are disseminating worldwide in hospital settings and have also been observed in healthy children of Peru. Multilocus sequence typing showed a diverse pool of E. coli strains carrying this resistance that were not always host species‐specific, suggesting sharing of strains between species or infection from a common source. This study shows widespread ESBL resistance in wild and domestic animals, supporting animal communities as a potential source of resistance. Future work is needed to elucidate the role of bats in the dissemination of antibiotic‐resistant strains of public health importance and to understand the origin of the observed resistance.  相似文献   

4.
The bacterial load and degree of antibiotic resistance present in untreated and antibiotic‐treated semen samples were investigated in five bulls standing at a cattle‐breeding centre. Bacterial load was determined by colony counts from semen samples cultured on brain heart infusion and nutrient agar plates. Antibiotic resistance in these bacteria was assessed by measuring the diameter of bacterial growth inhibition zones around discs containing different concentrations of antibiotics. Representative antibiotic‐resistant bacterial isolates were selected for identification. Untreated semen contained few culturable bacteria, and all were completely sensitive to gentamycin, spectinomycin and lincomycin: six of the isolates showed some resistance to tylosin. In semen to which antibiotics had been added as part of the routine production process, two isolates were sensitive to all of the antibiotics tested, and the remainder were resistant to all. Resistant Gram‐negative isolates that were identified included Pseudomonas and Stenotrophomonas spp. both in the class Gammaproteobacteria and a Sphingomonas sp. which is in the class Alphaproteobacteria.  相似文献   

5.
The aim of this research was to study the phenotypic resistances to disinfectants and antibiotics in strains of methicillin‐resistant Staphylococcus aureus (MRSA) obtained from Canary black pigs. Analyses were performed on 54 strains of MRSA, isolated in Canary black pigs from the province of Tenerife (Spain); all of them carried the mecA gene. The strains were isolated by means of nasal swab samples of healthy pigs, collected under veterinarian supervision. Bactericidal activity of antiseptics and disinfectants was tested by means of the dilution–neutralization method. Susceptibility to the disinfectants glutaraldehyde, peracetic acid and silver nitrate was assessed, as well as to the antiseptics chlorhexidine, benzalkonium chloride and povidone iodine. Susceptibility to a wide array of antibiotics representing the main groups was determined by means of the disc diffusion method. All the strains demonstrated susceptibility to the disinfectants tested at the recommended concentration, and even to dilutions equal to or lesser than 1/16. The most effective antiseptic and disinfectant were, respectively, chlorhexidine and silver nitrate. With regard to the antibiotics, the strains proved to be multiresistant. All presented phenotypic resistance to the β‐lactam antibiotics ampicillin, penicillin and cefoxitin, as well as to numerous aminoglycosides, tetracycline and trimethoprim–sulfamethoxazole. It was also observed that 61.1% of the strains were carriers of plasmids. Our results underline that in the strains such as MRSA, which show multiple resistances to antibiotics, the antiseptics and disinfectants show great efficacy. Moreover, as other authors also suggest, for the treatment and prevention of infections caused by MRSA, the use of β‐lactam and aminoglycoside antibiotics may be less effective.  相似文献   

6.
Increase in the number of small‐scale backyard poultry flocks in the USA has substantially increased human‐to‐live poultry contact, leading to increased public health risks of the transmission of multi‐drug resistant (MDR) zoonotic and food‐borne bacteria. The objective of this study was to detect the occurrence of Salmonella and MDR Gram‐negative bacteria (GNB) in the backyard poultry flock environment. A total of 34 backyard poultry flocks in Washington State (WA) were sampled. From each flock, one composite coop sample and three drag swabs from nest floor, waterer‐feeder, and a random site with visible faecal smearing, respectively, were collected. The samples were processed for isolation of Salmonella and other fermenting and non‐fermenting GNB under ceftiofur selection. Each isolate was identified to species level using MALDI‐TOFF and tested for resistance against 16 antibiotics belonging to eight antibiotic classes. Salmonella serovar 1,4,[5],12:i:‐ was isolated from one (3%) out of 34 flocks. Additionally, a total of 133 ceftiofur resistant (CefR) GNB including Escherichia coli (53), Acinetobacter spp. (45), Pseudomonas spp. (22), Achromobacter spp. (8), Bordetella trematum (1), Hafnia alvei (1), Ochrobactrum intermedium (1), Raoultella ornithinolytica (1), and Stenotrophomonas maltophilia (1) were isolated. Of these, 110 (82%) isolates displayed MDR. Each flock was found positive for the presence of one or more CefR GNB. Several MDR E. coli (n = 15) were identified as extended‐spectrum β‐lactamase (ESBL) positive. Carbapenem resistance was detected in non‐fermenting GNB including Acinetobacter spp. (n = 20), Pseudomonas spp. (n = 11) and Stenotrophomonas maltophila (n = 1). ESBL positive E. coli and carbapenem resistant non‐fermenting GNB are widespread in the backyard poultry flock environment in WA State. These GNB are known to cause opportunistic infections, especially in immunocompromised hosts. Better understanding of the ecology and epidemiology of these GNB in the backyard poultry flock settings is needed to identify potential risks of transmission to people in proximity.  相似文献   

7.
8.
Food animals are considered reservoirs of methicillin‐resistant Staphylococcus aureus (MRSA) and are implicated in their zoonotic transmission in the farm‐to‐plate continuum. LA‐MRSA has been reported as a zoonotic agent that has the potential to spread to humans and may cause infections in at‐risk groups. In this study, whole genome sequencing was used to describe the genetic environment (resistance mechanisms, virulence factors and mobile genetic elements) and investigate the genetic lineages of MRSA isolates from pigs in Cameroonian and South African abattoirs. During March–October 2016, 288 nasal and rectal pooled samples from 432 pigs as well as nasal and hand swabs from 82 humans were collected. Genomic DNA was sequenced using an Illumina MiSeq platform. Generated reads were de novo‐assembled using the Qiagen CLC Genomics Workbench and SPAdes. The assembled contigs were annotated, and antibiotic resistance genes, virulence factors, plasmids, SCCmec and phage elements were identified with ResFinder, Virulence Finder, PlasmidFinder, SCCmec Finder and PHAST, respectively. Core genome single nucleotide analysis was undertaken to assess clonal relatedness among isolates. A lower MRSA prevalence was observed in pigs in Cameroon (n = 1/13; 0.07%) compared with South Africa (n = 4/22; 18.18%), and none of the workers were colonized by MRSA. Genome analysis identified various antibiotic resistance genes along with six virulence factors in all isolates. All MRSA isolates belonged to the clonal lineage ST398 (spa‐type t011) and harboured the type Vc SCCmec and several plasmids. Our study shows that the livestock‐associated MRSA clonal lineage ST398 is already present in both Cameroon and South Africa and is probably underestimated in the absence of molecular epidemiological studies. It reveals the serious food safety and public health threat associated with this animal strain and underscores the need for interventions to contain this resistant clone.  相似文献   

9.
The dissemination of Enterobacteriaceae expressing resistance to extended‐spectrum cephalosporins, which are therapeutically used in both human and veterinary medicine, is of critical concern. The normal commensal flora of food animals may serve as an important reservoir for the zoonotic food‐borne transmission of Enterobacteriaceae harbouring β‐lactam resistance. We hypothesized that the predominant AmpC and ESBL genes reported in US livestock and fresh retail meat products, blaCMY‐2 and blaCTX‐M, would also be predominant in human enteric flora. We recovered enteric flora from a convenience sample of patients included in a large tertiary medical centre's Clostridium difficile surveillance programme to screen for and estimate the frequency of carriage of AmpC and ESBL resistance genes. In‐ and outpatient diarrhoeic submissions (n = 692) received for C. difficile testing at the medical centre's clinical diagnostic laboratory from July to December, 2013, were included. Aliquoted to a transport swab, each submission was inoculated to MacConkey broth with cefotaxime, incubated at 37°C and then inoculated to MacConkey agars supplemented with cefoxitin and cefepime to select for the AmpC and ESBL phenotypes, with blaCMY and blaCTX‐M genotypes confirmed by PCR and sequencing. From the 692 diarrhoeic submissions, our selective culture yielded 184 isolates (26.6%) with reduced susceptibility to cefotaxime. Of these, 46 (6.7%) samples harboured commensal isolates carrying the AmpC blaCMY. Another 21 (3.0%) samples produced isolates harbouring the ESBL blaCTX‐M: 19 carrying CTX‐M‐15 and 2 with CTX‐M‐27. Our results indicate that β‐lactam resistance genes likely acquired through zoonotic food‐borne transmission are present in the enteric flora of this hospital‐associated population at lower levels than reported in livestock and fresh food products.  相似文献   

10.
The objectives of this study were to (i) compare the carriage of Campylobacter and antimicrobial‐resistant Campylobacter among livestock and mammalian wildlife on Ontario farms, and (ii) investigate the potential sharing of Campylobacter subtypes between livestock and wildlife. Using data collected from a cross‐sectional study of 25 farms in 2010, we assessed associations, using mixed logistic regression models, between Campylobacter and antimicrobial‐resistant Campylobacter carriage and the following explanatory variables: animal species (beef, dairy, swine, raccoon, other), farm type (swine, beef, dairy), type of sample (livestock or wildlife) and Campylobacter species (jejuni, coli, other). Models included a random effect to account for clustering by farm where samples were collected. Samples were subtyped using a Campylobacter‐specific 40 gene comparative fingerprinting assay. A total of 92 livestock and 107 wildlife faecal samples were collected, and 72% and 27% tested positive for Campylobacter, respectively. Pooled faecal samples from livestock were significantly more likely to test positive for Campylobacter than wildlife samples. Relative to dairy cattle, pig samples were at significantly increased odds of testing positive for Campylobacter. The odds of isolating Campylobacter jejuni from beef cattle samples were significantly greater compared to dairy cattle and raccoon samples. Fifty unique subtypes of Campylobacter were identified, and only one subtype was found in both wildlife and livestock samples. Livestock Campylobacter isolates were significantly more likely to exhibit antimicrobial resistance (AMR) compared to wildlife Campylobacter isolates. Campylobacter jejuni was more likely to exhibit AMR when compared to C. coli. However, C. jejuni isolates were only resistant to tetracycline, and C.  coli isolates exhibited multidrug resistance patterns. Based on differences in prevalence of Campylobacter spp. and resistant Campylobacter between livestock and wildlife samples, and the lack of similarity in molecular subtypes and AMR patterns, we concluded that the sharing of Campylobacter species between livestock and mammalian wildlife was uncommon.  相似文献   

11.
Florfenicol is an important antibiotic in veterinary medicine that is used extensively in aquaculture, including salmon farming in Chile. We analysed a set of 119 florfenicol‐resistant Gram‐negative bacilli from seven freshwater Chilean salmon farms for the molecular determinants involved in the florfenicol resistance. Ninety‐seven of these strains were glucose non‐fermenting bacilli, mainly belonging to the Pseudomonas genus, whereas 22 strains were glucose‐fermenters. The floR gene was detected in 26 strains (21.8%) that had been isolated from three of the seven salmon farms. Most of the floR‐carrying strains were glucose fermenters (21 strains), and most of the floR‐carrying strains were also resistant to streptomycin, chloramphenicol and oxytetracycline. The minimum inhibitory concentrations against florfenicol were assessed in the presence and absence of the efflux pump inhibitor Phe‐Arg‐β‐naphthylamide (MC‐207,110). There was evidence that in the majority of non‐fermenting bacteria (82 strains), florfenicol resistance was at least partially mediated by non‐specific efflux pump systems. Given the diversity of antibiotic resistance patterns observed in this study in the floR‐positive isolates, a single antibiotic has the potential to co‐select for a diversity of resistances. For this reason, human health as well as animal health can potentially be impacted by the use of antibiotics in aquaculture. To assess this potential risk, future studies should focus on the ability of different antibiotics used in aquatic environments to co‐select for multiple resistances, the molecular basis of this diversity of resistance, and whether the genes conferring resistance can be transferred to other bacteria, including those of human health concern.  相似文献   

12.
We investigated the prevalence of Hepatitis E Virus (HEV), Leptospira and Ascaris suum (A. suum) seropositivity, and of nasal methicillin‐resistant Staphylococcus aureus (MRSA) colonization among Austrian practising veterinarians, and assessed the association with occupational swine livestock exposure. The 261 participants completed a questionnaire on demographics, intensity of occupational swine livestock contact and glove use during handling animals and their secretions. Participants' blood samples were tested for HEV, Leptospira and A. suum seropositivity and nasal swabs cultured for MRSA. We compared swine veterinarians (defined as >3 swine livestock visits/week) to non‐swine veterinarians (≤3 swine livestock visits/week) with regard to the outcomes through calculating prevalence ratio (PR) and 95% confidence interval (CI). Furthermore, the relationship between occupational swine livestock contact and the study outcomes was examined by age (</≥55 years) and glove usage. The prevalence of nasal MRSA colonization was 13.4% (95% CI: 9.3–17.6), of HEV seropositivity 20.8% (95% CI: 15.8–25.7) and A. suum seropositivity 44% (95% CI: 37.7–50.2). The highest anti‐leptospiral antibodies titres were 1:200 (L. hebdomadis) and 1:100 (L. autumnalis, L. caicola) found in three non‐swine veterinarians. Compared to non‐swine veterinarians, swine veterinarians were 1.9 (95% CI: 1.0–3.4) and 1.5 (95%CI: 1.0–2.3) times more likely HEV seropositive and A. suum seropositive, respectively, and 4.8 (95%CI: 2.5; 9.3) times more likely nasally colonized with MRSA. Among glove‐using veterinarians, occupational swine contact was no longer a determinant for HEV seropositivity (PR 1.6; 95% CI: 0.8–2.9). Similar was found for A. suum seropositivity, which was no longer associated with occupational swine livestock contact in the subgroup of glove using, ≥55‐year‐old veterinarians (PR: 1.07; 95% CI: 0.4–3.3). Our findings indicate that >3 occupational swine livestock visits per week is associated with HEV and A. suum seropositivity and nasal MRSA colonization and that glove use may play a putative preventive role in acquiring HEV and A. suum. Further analytical epidemiological studies have to prove the causality of these associations.  相似文献   

13.
Antimicrobial resistance poses a significant threat to the continued successful use of antimicrobial agents for the treatment of bacterial infections. While the epidemiology of antimicrobial resistance in bacteria from man has been studied extensively, less work has been undertaken in companion animals, particularly horses. Methicillin‐resistant Staphylococcus aureus has been identified as a cause of infections, with a low prevalence of nasal carriage by horses in the community but higher for hospitalised horses. Molecular characterisation has shown methicillin‐resistant Staphylococcus aureus strains either to be predominantly of types associated with horses or of sequence type ST398. Antimicrobial‐resistant Escherichia coli (including multidrug‐resistant and extended spectrum β‐lactamase‐producing isolates) have caused infections and been documented in faecal carriage by horses, with many significant resistance mechanisms identified. More sporadic reports and molecular characterisation exist for resistance in other bacteria such as enterococci, Salmonella, Acinetobacter and Pseudomonas species. Limited work has been undertaken evaluating risk factors and much of the epidemiology of antimicrobial resistance in bacteria from horses remains to be determined.  相似文献   

14.
Although leopard geckos (Eublepharis macularius) are commonly kept under human care, their vitamin requirements are largely unknown. Many invertebrate preys display a low vitamin A concentration; thus, gut‐loading insects with vitamin A or carotenoids is a common practice. The objective of this prospective experimental study was to investigate whether dietary supplementation with β‐carotene, including prey gut‐loading, leads to sufficient vitamin A hepatic storage and prevents epithelial squamous metaplasia development in leopard geckos. Ten clinically healthy female leopard geckos were randomly divided in two groups with various supplementations: a group receiving vitamin A supplementation and a group receiving β‐carotene. Insects were gut‐loaded continuously with a supplement containing vitamin A or β‐carotene, depending on the group. Oral supplementation with cod liver oil or carrot juice was administered weekly to each lizard from “vitamin A group” and “carotenoid group” respectively. After 10 weeks of supplementation, surgical hepatic biopsies were obtained in three geckos of each group while the two remaining geckos were euthanized to undergo complete necropsy. Hepatic vitamin A concentration was determined for each lizard (n = 10) by ultra‐performance liquid chromatography. Histopathology revealed hepatocellular vacuolization and vitellogenic follicles in five females. Epithelial squamous metaplasia was not observed in any of the geckos. Hepatic vitamin A concentration was significantly higher in the carotenoid‐supplemented group than in the vitamin A‐supplemented group (p = 0.03). Our results suggest that in leopard geckos, dietary supplementation with β‐carotene allows sufficient vitamin A hepatic storage.  相似文献   

15.
To investigate public health implications of antibiotics to control post‐weaning scours, we surveyed 22 commercial pig herds in southeastern Australia. Fifty faecal samples per herd were collected from pre‐ and post‐weaned piglets. Presumptive Escherichia coli isolates were confirmed by MALDI‐TOF MS. Isolates (n = 325) were screened for susceptibility to 19 veterinary antibiotics using MIC broth microdilution. All 325 E. coli isolates underwent further testing against 27 antibiotics used in human medicine and were screened for ETEC adhesin and enterotoxin genes (F4 (K88), F5 (K99), F6 (987P), F18, F41, STa, STb, Stx2e and LT) by multiplex PCR. Isolates identified as phenotypically resistant to third‐generation cephalosporin (3GC) and aminoglycoside antibiotics were screened by multiplex PCR/reverse line blot to detect common β‐lactam and aminoglycosides resistance genes, confirmed by sequencing. Twenty (6.1%) of the E. coli isolates were resistant to 3GC antibiotics and 24 (7.4%) to the aminoglycoside antibiotic gentamicin. Genetic analysis revealed six different extended spectrum β‐lactamase (ESBL) genes (blaCTX‐M‐1, ‐14, ‐15, ‐27, blaSHV‐12 and blaCMY‐2‐like genes), four of which have not been previously reported in Australian pigs. Critically, the prevalence of 3GC resistance was higher in non‐pathogenic (non‐ETEC) isolates and those from clinically normal (non‐diarrhoeal) samples. This highlights the importance of non‐ETECE. coli as reservoirs of antimicrobial resistance genes in piglet pens. Antimicrobial resistance surveillance in pig production focused on diagnostic specimens from clinically‐affected animals might be potentially misleading. We recommend that surveillance for emerging antimicrobial resistance such as to 3GC antibiotics should include clinically healthy pigs.  相似文献   

16.
The role of free‐ranging wildlife in the epidemiology of enteropathogens causing clinical illness in humans and domestic animals is unclear. Salmonella enterica and anti‐microbial resistant bacteria have been detected in the faeces of raccoons (Procyon lotor), but little is known about the carriage of these bacteria in other sympatric meso‐mammals. Our objectives were to: (a) report the prevalence of Salmonella and associated anti‐microbial resistance, Campylobacter spp, Clostridium difficile, and anti‐microbial resistant Escherichia coli in the faeces of striped skunks (Mephitis mephitis) and Virginia opossums (Didelphis virginiana) in southern Ontario; and (b) compare the prevalence of these bacteria in the faeces of these meso‐mammal hosts with raccoons from a previously reported study. Faecal swabs were collected from striped skunks and Virginia opossums on five swine farms and five conservation areas from 2011 to 2013. Salmonella was detected in 41% (9/22) and 5% (5/95) of faecal swabs from Virginia opossums and striped skunks, respectively. None of the Salmonella serovars carried resistance to anti‐microbials. The prevalence of Campylobacter spp., C. difficile, and anti‐microbial resistant E. coli ranged from 6% to 22% in striped skunk and Virginia opossums. Using exact logistic regression, Salmonella was significantly more likely to be detected in faecal swabs of Virginia opossums than skunks and significantly less likely in faecal swabs from skunks than raccoons from a previously reported study. In addition, Campylobacter spp. was significantly more likely to be detected in raccoons than opossums. Salmonella Give was detected in 8/9 (89%) of Salmonella‐positive Virginia opossum faecal swabs. Our results suggest that striped skunks and Virginia opossums have the potential to carry pathogenic enteric bacteria in their faeces. The high prevalence of Salmonella Give in Virginia opossum faecal swabs in this study as well as its common occurrence in other Virginia opossum studies throughout North America suggests Virginia opossums may be reservoirs of this serovar.  相似文献   

17.
Most embalming of cadavers for anatomical dissection in veterinary medicine has used 6-10% formaldehyde resulting in discoloured and rigid specimens. This project produced teaching specimens of sheep, horse and calf cadavers having their musculoskeletal and visceral structures with a natural appearance using a fixation solution with lowered concentrations of formaldehyde (2% and 3%) together with ethanol and polyethylene glycols. Fixation parameters (palpable consistency, flexibility, colour, tissue hydration and odour) were assessed qualitatively by twice weekly dissections over two months for sheep and three months for horses and calf. Formaldehyde levels, measured in the breathing zone, were below the maximum allowable concentration in all specimens except for a 300 kg horse cadaver. To evaluate the effectiveness of the fixation solution in microbial inhibition, tissue samples were taken and analyzed for the presence of culturable aerobic and anaerobic bacteria, yeasts and moulds. Single colonies of Pseudomonas oryzihabitans, Chryseobacterium sp., Acinetobacter sp. were isolated from lungs, and Micrococcus sp. and Bacillus sp. were isolated from one muscle sample.  相似文献   

18.
MRSA CC398 is an emerging MRSA strain found in livestock, mainly in pigs. Direct occupational livestock contact is the principal risk factor for human MRSA CC398 infection. Nonetheless, in recent years, an increasing number of MRSA CC398 cases has been observed in persons without known pig contact. Such cases, referred to as MRSA CC398 of unknown origin (MUO CC398), have, like livestock‐onset (LO) MRSA CC398 cases, been found concentrated in rural, livestock‐producing areas. The presence of MUO CC398 cases indicates alternative and unknown MRSA CC398 transmission pathways into the community. We performed a nationwide study in Denmark of the geographic distributions of MRSA cases in general and persons with MUO CC398 or LO MRSA CC398 infections (1 January 2006–11 February 2015), with the Danish population as background population. Place of living of study persons was mapped using the ArcGIS software, and information on pig farms was retrieved from the Central Husbandry Register. The incidence of MUO CC398 infections was clearly higher in rural than in urban areas, and such cases lived on average closer to pig farms than the general population. However, within three pig‐farming‐dense municipalities, patients with MUO CC398 infections did not live closer to pig farms than population controls. This shows that direct environmental spread from neighbouring pig farms of MRSA CC398 is unlikely. Instead, community spread through other means of transmission than direct spread from farms may more likely explain the clustering of MUO CC398 in livestock‐dense areas.  相似文献   

19.
A total of 52 Escherichia coli strains isolated from diarrhoeic rabbits were investigated for their enteropathogenic E. coli (EPEC) pathotype by PCR amplification of eae and bfp virulence genes. A total of 22 EPEC isolates were identified, serotyped and studied for antibiotic resistance and screened for the detection of extended‐spectrum β‐lactamases (ESBLs). The EPEC isolates belonged to three serogroups (O26, O92 and O103). The most common serogroup (O103:K‐:H2) was observed among 17 EPEC strains, the O92:K‐serogroup in three isolates (the antibiotic sensitive ones) and the remaining O26:K‐serogroup in two isolates (the ESBLs isolates). Resistances to ampicillin and tetracycline were the most frequent and detected followed by resistance to nalidixic acid, streptomycin, trimethoprim–sulphamethoxazole, cefoxitin, gentamicin and ciprofloxacin. All the isolates were sensitive for amikacin, ceftazidime, aztreonam, imipenem, chloramphenicol, tobramycin and amoxicillin + clavulanic acid. Two isolates recovered from two adult animals showed an intermediate susceptibility to cefotaxime, and a positive screening test for ESBL was demonstrated in both. The blaTEM gene was demonstrated in the majority of ampicillin‐resistant isolates. The aac(3)‐II or aac(3)‐IV genes were detected in the four gentamicin‐resistant isolates. In addition, the aadA gene was detected in 60% of streptomycin‐resistant isolates. The tet(A) or tet(B) genes were identified in all tetracycline‐resistant isolates. A total of nine EPEC isolates showed the phenotype SXT‐resistant, and the sul1 and/or sul2 and/or sul3 genes were detected in all of them. Our findings showed that the molecular detection by the eae and bfp genes by PCR followed by serotyping is useful for monitoring trends in EPEC infections of rabbits allowing the identification of their possible reservoirs. The detection of genes involved in the resistance to antibiotics of different families in a relatively high proportion of faecal E. coli isolates of rabbits is of great interest and could be considered a serious public health problem.  相似文献   

20.
Data from 18 β‐carotene‐deficient Japanese Black cows were collected to clarify the effects of feeding β‐carotene‐enriched dry carrots on β‐carotene status and colostral immunoglobulin (Ig) in cows. Cows were assigned to control or carrot groups from 3 weeks before the expected calving date to parturition, and supplemental β‐carotene from dry carrots was 138 mg/day in the carrot group. Plasma β‐carotene concentrations in the control and carrot groups at parturition were 95 and 120 μg/dL, and feeding dry carrots slightly improved plasma β‐carotene at parturition. Feeding dry carrots increased colostral IgA concentrations in cows and tended to increase colostral IgG1, but colostral IgM, IgG2, β‐carotene and vitamin A were not affected by the treatment. Feeding dry carrots had no effects on plasma IgG1, IgA and IgM concentrations in cows, but plasma IgG1 concentrations decreased rapidly from 3 weeks before the expected calving date to parturition. These results indicate that feeding β‐carotene‐enriched dry carrots is effective to enhance colostral IgA and IgG1 concentrations in β‐carotene‐deficient cows.  相似文献   

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