Determination of Antibiotic Resistance Phenotypes and Genotypes in E. coli Isolates in Pigs in West Romanian Grower Farms | Chapter 2 | New Visions in Medicine and Medical Science Vol. 4

 The present study investigated genes normally associated with plasmid carriage in terms of differential phenotypic resistance profiles and evaluated the contribution of selected resistance genes to the phenotypic expression of susceptibility and resistance. Antibiotics are widely used for prophylaxis and therapy, reducing morbidity and mortality produced by bacterial pathogensin pigs, including infections caused by Escherichia coli. Differential phenotypic susceptibility profiles and the contribution of resistance genes to phenotypic expression of susceptibility or resistance were evaluated. A total of 76 E. coli isolates were identified and confirmed by the MicroScan Walk Away System. The occurrence of four resistance genes, ampC, blaZ, blaTEM and tetK in strains resistant to 13 antibiotics was assessed. Of the E. coli isolates, 0% showed resistance to meropenem, 3.9% to tigecycline and 10.5% to piperacillin / tazobactam, whereas, in contrast, 100% were resistant to ampicillin and mezlocillin, 76.31% to piperacillin and 59.3% to tetracycline. The prevalence of resistance genes in resistant isolates detected by q-PCR analysis was 97.0% for ampC, 96% for blaZ, 32.9% for blaTEM and 58.8% for tetK. Penetrance (the proportion of individuals carrying a particular variant of a gene that also expresses an associated trait) was 50% for ampC (32% for amoxicillin/ clavulanate, 62% for cefazolin, 32% for cefepime, 100% for cefotaxime, 56% for cefuroxime and 99% for ampicillin), 65% for blaZ (32% for amoxicillin/clavulanate and 99% for ampicillin), 51% for blaTEM (81% for piperacillin) and 44% for the tetK gene (83% for tetracycline). The result of phenotypic antibiotic resistance testing may indicate the presence of plasmid-borne resistance, with a diagnostic odds ratio of a positive phenotypic resistance for tetK being 4.52. As a management decision, the maximum penetrance admitted for using a specific antibiotic for E. coli infections in pigs is recommended to be less than 20%. The correlation of phenotypic and genotypic resistance with a limited number of plasmid-mediated resistance genes points to the value of penetrance (percentage of strains showing resistance as a phenotype compared with the number showing the resistance genotype) as a parameter which may be used as guidance for a more accurate targeting of chemotherapy for E. coli.

Author(s) Details:

Bianca Cornelia Lungu,
Horia Cernescu Research Unit, Faculty of Veterinary Medicine, University of Life Sciences King Michael I, Calea Aradului 119, 300645 Timisoara, Romania.

Ioan Hutu,
Ioan Hutu (Associate Professor of Animal Breeding and Production)

Paul Andrew Barrow,
Environmental Health, Faculty of Public Health, Universitas Muhammadiyah Kalimantan, Timur, Indonesia.

Please see the link here: https://stm.bookpi.org/NVMMS-V4/article/view/13998

Resistance Breeding in Ornamental Plants: An Overview | Chapter 5 | Emerging Issues in Agricultural Sciences Vol. 5

 This branch highlights Resistance rearing in ornamental plants. Use of resistant types leads to reduction in the use of pesticides that in turn results in reduction of loud noises and health hazards induced using pesticides. Moreover, genetic opposition protects natural opponents of insect pest that are killed by insecticides. A order of studies have been transported for the identification and cloning of genes fit increasing fortitude to environmental stresses like drought, frosty, heat, salinity, metal toxicity, hypoxia, and UV-B dissemination. Somaclonal variation has contributed to the incident of abiotic stress resistant types in major crops. Mutation techniques containing transposon mutagenesis have made to the understanding of the microscopic basis of the plant stress response established the information assembled from the Arabidopsis and other model studies. Other methods used to develop new genotypes tolerant to cold, dryness and salt are expansive distant hybridization, In-vitro mutagenesis and alteration of genetic material. Breeding for biotic stress opposition deals with defense systems and strategies that cover host plants against pests and pathogens, inheritance of opposition genes and durable influence of resistance genes.

Author(s) Details:

Tulipa De,
Uttar Banga Krishi Viswavidyalaya, Pundibari, Cooch Behar, West Bengal, India.

Achyuta Basak,
Uttar Banga Krishi Viswavidyalaya, Pundibari, Cooch Behar, West Bengal, India.

L. C. De,
ICAR-National Research Centre for Orchids, Pakyong, Sikkim, India.

Please see the link here: https://stm.bookpi.org/EIAS-V5/article/view/11138