Examinando por Autor "Galarce, Nicolás"
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Ítem Advances in Integrated Antimicrobial Resistance Surveillance and Control Strategies in Asia-Pacific Economic Cooperation Economies: Assessment of a Multiyear Building Capacity Project(MDPI, 2022-08) Cornejo, Javiera; Asenjo, Gabriela; Zavala, Sebastian; Venegas, Lucas; Galarce, Nicolás; Hormazábal, Juan Carlos; Vergara E, Constanza; Lapierre, LisetteAntimicrobial resistance (AMR) is a growing global health concern for both animal and public health, and collaborative strategies are needed to combat the threat. The level of awareness and funding for policies focused on reducing AMR varies between countries. The aim of this study was to compare the integrated surveillance systems for AMR in high and low–middle economies of the Asia-Pacific Economic Cooperation and determine whether there was any improvement from 2015 to 2018. We conducted a survey with a group of 21 countries at different development levels. Associations between the economic development level and the questions of AMR awareness and funding were established using Fisher’s exact test. Improvements were identified where countries established public policies for integrated surveillance of AMR. High economies showed greater advancement in several topics related to AMR than low–middle economies. The survey revealed that there is a better understanding surrounding the implications of the emergence of AMR in human medicine than in veterinary medicine, agriculture, and food production. Our results show that countries enhanced overall AMR surveillance over the 4-year-period; however, more research is needed concerning these advances, especially in low–middle economies and the food production sector. © 2022 by the authors.Ítem Estimates of Effective Population Size in Commercial and Hatchery Strains of Coho Salmon (Oncorhynchus kisutch (Walbaum, 1792))(MDPI, 2022-03) Martinez, Victor; Dettleff, Phillip J.; Galarce, Nicolás; Iwamoto, Robert N.; Naish, Kerry; Bravo, Cristian; Dorner, JessicaUnderstanding the genetic status of aquaculture strains is essential for developing management guidelines aimed at sustaining the rates of genetic gain for economically important traits, as well as securing populations that will be robust to climate change. Coho salmon was the first salmonid introduced to Chile for commercial purposes and now comprises an essential component of the country’s aquaculture industry. Several events, such as admixture, genetic bottlenecks, and rapid domestication, appear to be determinants in shaping the genome of commercial strains representing this species. To determine the impact of such events on the genetic diversity of these strains, we sought to estimate the effective population size (Ne) of several of these strains using genome-wide approaches. We compared these estimates to commercial strains from North America and Japan, as well as a hatchery strain used for supportive breeding of wild populations. The estimates of Ne were based on a method robust to assumptions about changes in population history, and ranged from low (Ne = 34) to relatively high (Ne = 80) in the Chilean strains. These estimates were higher than those obtained from the commercial North American strain but lower than those observed in the hatchery population and the Japanese strain (with Ne over 150). Our results suggest that some populations require measures to control the rates of inbreeding, possibly by using genomic information and incorporating new genetic material to ensure the long-term sustainability of these populations. © 2022 by the authors. Licensee MDPI, Basel, Switzerland.Ítem Phenotypic and genotypic antimicrobial resistance in Escherichia coli strains isolated from household dogs in Chile(Frontiers Media SA, 2023) Galarce, Nicolás; Arriagada, Gabriel; Sánchez, Fernando; Escobar, Beatriz; Miranda, Mauricio; Matus, Sofía; Vilches, Rocío; Varela, Camila; Zelaya, Carlos; Peralta, Josefa; Paredes-Osses, Esteban; González-Rocha, Gerardo; Lapierre, LisetteIntroduction: Antimicrobial resistance (AMR) is a major threat to animal and public health worldwide; consequently, several AMR surveillances programs have been implemented internationally in both human and veterinary medicine, including indicator bacteria such as Escherichia coli. However, companion animals are not typically included in these surveillance programs. Nevertheless, there have been reports of increasing levels of antimicrobial resistance in E. coli strains isolated from dogs worldwide. In Chile, there is limited information available on AMR in E. coli isolated from companion animals, which prevents the establishment of objective prevention and control measures. Methods: For this reason, the aim of this study was to characterize the phenotypic and genotypic AMR of E. coli strains isolated from healthy household dogs in Chile. For this purpose, a multi-stage sampling was carried out in the Metropolitan Region of Chile, obtaining samples from 600 healthy dogs. These samples were processed using traditional bacteriology and molecular techniques to isolate E. coli strains. We assessed the minimal inhibitory concentration of 17 antimicrobials and conducted a search of six antimicrobial resistance genes, as well as class 1 and 2 integrons, in the isolated strains. Results: Two-hundred and twenty-four strains of E. coli were recovered, and 96.9% (n = 217) showed resistance to at least one drug and only 3.1% (n = 7) were susceptible to all analyzed antimicrobials. Most strains were resistant to cefalexin (91.5%, n = 205, 1st-generation cephalosporin), followed by ampicillin (68.3%, n = 153) and cefpodoxime (31.3%, n = 70, 3rd-generation cephalosporin). Moreover, 24.1% (n = 54) tested positive for extended-spectrum-β-lactamases and 34.4% (n = 77) were multidrug resistant. As for the AMR genes, the most detected was qnrB (28.1%, n = 63), followed by blaCTX-M (22.3%, n = 50), and blaTEM-1 (19.6%, n = 44). Additionally, 16.1% (n = 36) harbored class 1 integrons. Our study shows that E. coli strains isolated from healthy household dogs exhibit resistance to several relevant drugs and also antimicrobial resistance genes considered critical for human health. These results can be used as a starting point for the prevention and control of antimicrobial resistance from companion animals. This background should be considered when formulating future resistance surveillance programs or control plans in which companion animals must be included. Copyright © 2023 Galarce, Arriagada, Sánchez, Escobar, Miranda, Matus, Vilches, Varela, Zelaya, Peralta, Paredes-Osses, González-Rocha and Lapierre.Ítem Virulence and antimicrobial resistance factors in Salmonella enterica serotypes isolated from pigs and chickens in central Chile(Frontiers Media S.A., 2022-09) Retamal, Patricio; Gaspar, Joaquim; Benavides, María Belén; Saenz, Leonardo; Galarce, Nicolás; Aravena, Trinidad; Cornejo, Javiera; Lapierre, LisetteSalmonella enterica is a food-borne pathogen with a wide host-range that during decades has been of public health concern in developed and developing countries. In Chile, the poultry and pig industries represent the biggest contribution of meat consumption in the population, and sanitary regulations have been imposed for Salmonella control. The aim of this work was to determine and characterize Salmonella strains isolated from pigs and chicken raised on commercials farms in Chile. For this, isolates belonging to pigs (n = 46) and poultry (n = 57) were genotyped by two multiplex PCR reactions and virulotyped by the PCR detection of virulence-associated genes. In addition, isolates were serotyped and analyzed by the Kirby Bauer assay to determine their antimicrobial resistance phenotypes. From these analyses 52 genotypes, six serotypes and several multidrug resistance phenotypes and different combinations of virulence-associated genes were detected. These results suggest that S. enterica in pigs and poultry in central Chile should be monitored due to potential consequences in public and animal health. Copyright © 2022 Retamal, Gaspar, Benavides, Saenz, Galarce, Aravena, Cornejo and Lapierre.