scholarly journals Genetic diversity and antimicrobial resistance inStaphylococcus aureusand coagulase‐negativeStaphylococcusisolates from bovine mastitis in Minas Gerais, Brazil

2018 ◽  
Vol 8 (5) ◽  
pp. e00736 ◽  
Author(s):  
Elaine M. S. Dorneles ◽  
Mariana D. A. M. Fonseca ◽  
Juliana A. P. Abreu ◽  
Andrey P. Lage ◽  
Maria A. V. P. Brito ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Antimicrobial Resistance ◽  
Bovine Mastitis ◽  
Minas Gerais

Presence of Classical Enterotoxin Genes, agr Typing, Antimicrobial Resistance, and Genetic Diversity of Staphylococcus aureus from Milk of Cows with Mastitis in Southern Brazil

2018 ◽  
Vol 81 (5) ◽  
pp. 738-742 ◽  
Author(s):  
ISABELA S. KRONING ◽  
MARIANA A. IGLESIAS ◽  
KARLA S. MENDONÇA ◽  
GRACIELA V. LOPES ◽  
WLADIMIR P. SILVA
Keyword(s):  
Genetic Diversity ◽  
Antimicrobial Resistance ◽  
Antimicrobial Agents ◽  
Bovine Mastitis ◽  
Disease Outbreaks ◽  
Southern Brazil ◽  
Group Iii ◽  
Distinct Area ◽  
Group I ◽  
Enterotoxin Genes

ABSTRACTStaphylococcus aureusis a common causative agent of bovine mastitis in dairy cows and commonly associated with foodborne disease outbreaks. The aim of this study was to evaluate the presence of enterotoxin genes, agr typing, antimicrobial resistance, and genetic diversity of S. aureus isolated from milk of cows with mastitis in dairy farms from southern Brazil. Results showed that 7 (22.6%) of 31 S. aureus isolates were positive for enterotoxin genes. Specifically, the genes encoding for enterotoxins A (n = 4), C (n = 2), and B (n = 1) were detected. Isolates belonging to the agr group III (10 of 31, 32.2%) and agr group I (7 of 31, 22.5%) were the most common. To our knowledge, this is the first report of both agr I and III in the same S. aureus isolate from milk of cows with bovine mastitis. The antimicrobial resistance test showed that 54% of the isolates were multiresistant to antimicrobial agents. The macrorestriction analysis produced 16 different major SmaI pulsed-field gel electrophoresis patterns, with up to two subpatterns. Moreover, the presence of some S. aureus clones in a distinct area was observed. Although this study characterized a limited number of S. aureus isolates, the presence of classical enterotoxin genes and resistance to multiple antimicrobial agents reinforces the importance of this microorganism to animal and human health. In addition, similar genetic profiles have been identified in distinct geographic areas, suggesting clonal dissemination of S. aureus in dairy herds from southern Brazil.

scholarly journals Whole genome-based characterisation of antimicrobial resistance and genetic diversity in Campylobacter jejuni and Campylobacter coli from ruminants

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Medelin Ocejo ◽  
Beatriz Oporto ◽  
José Luis Lavín ◽  
Ana Hurtado
Keyword(s):  
Genetic Diversity ◽  
Antimicrobial Resistance ◽  
Campylobacter Jejuni ◽  
Resistance Genes ◽  
Campylobacter Coli ◽  
Whole Genome ◽  
Northern Spain ◽  
Sequence Alignments ◽  
Phenotypic Data ◽  
Wide Range

AbstractCampylobacter, a leading cause of gastroenteritis in humans, asymptomatically colonises the intestinal tract of a wide range of animals.Although antimicrobial treatment is restricted to severe cases, the increase of antimicrobial resistance (AMR) is a concern. Considering the significant contribution of ruminants as reservoirs of resistant Campylobacter, Illumina whole-genome sequencing was used to characterise the mechanisms of AMR in Campylobacter jejuni and Campylobacter coli recovered from beef cattle, dairy cattle, and sheep in northern Spain. Genome analysis showed extensive genetic diversity that clearly separated both species. Resistance genotypes were identified by screening assembled sequences with BLASTn and ABRicate, and additional sequence alignments were performed to search for frameshift mutations and gene modifications. A high correlation was observed between phenotypic resistance to a given antimicrobial and the presence of the corresponding known resistance genes. Detailed sequence analysis allowed us to detect the recently described mosaic tet(O/M/O) gene in one C. coli, describe possible new alleles of blaOXA-61-like genes, and decipher the genetic context of aminoglycoside resistance genes, as well as the plasmid/chromosomal location of the different AMR genes and their implication for resistance spread. Updated resistance gene databases and detailed analysis of the matched open reading frames are needed to avoid errors when using WGS-based analysis pipelines for AMR detection in the absence of phenotypic data.

scholarly journals Genetic diversity of Annona crassiflora (Annonaceae) in northern Minas Gerais State

2011 ◽  
Vol 10 (3) ◽  
pp. 2172-2180 ◽  
Author(s):  
L.G. Cota ◽  
F.A. Vieira ◽  
A.F. Melo Júnior ◽  
M.M. Brandão ◽  
K.N.O. Santana ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Minas Gerais ◽  
Minas Gerais State ◽  
Annona Crassiflora

scholarly journals Genetic diversity, virulence genotype and antimicrobial resistance of uropathogenic Escherichia coli (UPEC) isolated from sows

2018 ◽  
Vol 38 (1) ◽  
pp. 79-87 ◽  
Author(s):  
Maria G. Spindola ◽  
Marcos P. V. Cunha ◽  
Luisa Z. Moreno ◽  
Cristina R. Amigo ◽  
Ana P. S. Silva ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Genetic Diversity ◽  
Antimicrobial Resistance ◽  
Uropathogenic Escherichia Coli

scholarly journals Phenotypic and Genotypic Characteristics and Resistance Profile of Staphylococcus spp. from Bovine Mastitis

2020 ◽  
Vol 48 ◽  
Author(s):  
Érica Chaves Lucio ◽  
Gisele Veneroni Gouveia ◽  
Mateus Matiuzzi Da Costa ◽  
Mário Baltazar De Oliveira ◽  
Rinaldo Aparecido Mota ◽  
...  
Keyword(s):  
Antimicrobial Resistance ◽  
Milk Production ◽  
Biofilm Formation ◽  
Negative Impact ◽  
Meca Gene ◽  
Bovine Mastitis ◽  
Resistant Bacteria ◽  
Production Chain ◽  
Biofilm Production ◽  
Staphylococcus Spp

Background: Bovine mastitis remains one of the health problems that cause the most damage to milk producers. The negative impact of mastitis is due to reduced milk production, early slaughter of females, reduced commercial value of the affected animals, losses in the genetic potential of the herd, expenses with medicines and veterinary medical assistance. Staphylococcus spp. stands out as the cause of this disease and has been able to remain in the mammary gland, becoming resistant to several antimicrobials. The aims of the present study were to characterize the phenotypes, genotypes and resistance profiles of Staphylococcus spp. isolates from bovine mastitis cases in the state of Pernambuco, Brazil.Materials, Methods & Results: These isolates were classified according to biochemical tests and the presence of the nuc gene.  The polymerase chain reaction (PCR) for amplification of the mecA and blaZ genes was used to analyze the genetic potentials of antimicrobial resistance. Isolates were also phenotypically tested for resistance to nine antimicrobials (ampicillin, doxicillin, erythromycin, gentamicin, rifampicin, cephalothin, amoxicillin, nalidixic acid and oxacillin). The genetic potentials for biofilm production were evaluated by the amplifications of the icaD, icaA and bap genes. The phenotypic test of gentian violet was used for biofilm formation analyzes. Ninety-three (93.0%) of the isolates among the Staphylococcus spp. samples were classified as Staphylococcus aureus. The lowest percentage of sensitivity observed was for amoxicillin (28.0%). All of the isolates were sensitive to erythromycin and gentamicin, and 15 (15%) exhibited sensitivity to all of the drugs tested. All of the isolates were negative for the mecA gene, and 36 (36%) were positive for blaZ. In the adhesion microplate tests, 44 (44%) of the isolates were capable of biofilm formation. Of these, seven (15.9%) were strong formers, whereas 16 (36.3%) and 21 (47.8%) were moderate and weak formers, respectively. The icaD gene was confirmed in 89 (89%) of the isolates. The icaA gene was confirmed in 61 (61%) samples, and the bap gene in 52 (52%) samples. One of the samples did not possess icaA, icaD or bap and exhibited moderate biofilm formation according to the microplate adherence test. Sixteen isolates simultaneously exhibited the three genes tested for biofilm production (icaA, icaD and bap) and were negative according to the microplate adherence test.Discussion:  The indiscriminate use of antibiotics to treat mastitis is a common practice in the study area, which may have contributed to the high proportion of herds (88.23%; 15/17) with multi-resistant isolates, constituting a selection factor for the dissemination of resistant bacteria among herds.  The absence of the mecA gene in the present study may be associated with the development of resistant bacteria through another mechanism, such as the overproduction of beta-lactamases. The results demonstrate that antimicrobial resistance occurs in Staphylococcus spp. that cause bovine mastitis in herds of Pernambuco and that these isolates have the a great capacity for biofilm formation. It is necessary to sensitize the professionals involved in the milk production chain of Brazil regarding the importance of the adequate use of antimicrobials for the treatment and control of mastitis, since studies in the country indicate the dissemination of resistant bacterial strains.

scholarly journals Genetic diversity and virulence genes in Streptococcus uberis strains isolated from bovine mastitis

2017 ◽  
Vol 38 (4Supl1) ◽  
pp. 2595 ◽  
Author(s):  
Rafael Ambrósio Loures ◽  
Ulisses De Pádua Pereira ◽  
Glei Dos Anjos de Carvalho-Castro ◽  
Gláucia Frasnelli Mian ◽  
Dircéia Aparecida da Costa Custódio ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Virulence Genes ◽  
Mammary Epithelial Cells ◽  
Bovine Mastitis ◽  
Mammary Epithelial ◽  
Molecular Characteristics ◽  
Dairy Herds ◽  
High Genetic Diversity ◽  
Streptococcus Uberis ◽  
Intensively Managed

Mastitis is one of the most common and costly infectious diseases in dairy cattle worldwide. This is a multifactorial illness caused by different microorganisms, including virus, yeasts, algae, parasites, and several species of bacteria. Among these bacteria, Streptococcus uberis is an important environmental pathogen that is responsible for a large range of clinical and subclinical mammary infections, especially in intensively managed herds. Despite the increasing importance of this pathogen in the etiology of bovine mastitis, data on its virulence and diversity in Brazilian dairy herds are scarce. The aims of the present study were to investigate the virulence characteristics of S. uberis isolated from bovine mastitis and to assess the molecular epidemiology of the Brazilian isolates using pulsed-field gel electrophoresis (PFGE). In this work, 46 strains of S. uberis isolated from bovine mastitis from 26 Brazilian dairy herds were evaluated regarding their genetic diversity by PFGE using with the SmaI enzyme. Additionally, the presence of the virulence genes skc and pauA, which encode plasminogen activators, and the gene sua, which encodes an adhesion molecule in mammary epithelial cells, were assessed by PCR. Our results showed a high genetic diversity in the population, displaying many different patterns in the PFGE analysis. A high proportion of strains was positive for virulence genes in the sampled population (sua [100%], pauA [91%], and skc [91%]). The high frequency of skc, pauA, and sua genes among the studied strains suggests the importance of these virulence factors, possibly helping S. uberis in the colonization of the bovine mammary gland. Surveys of the genetic and molecular characteristics of this pathogen can improve our knowledge of bacterial activity and identify molecules that have roles in the establishment of the infection. This might help in the development of more effective measures to control and prevent bovine mastitis.

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