Laura Beatriz Rodrigues

Dr. Laura Beatriz Rodrigues


Research Focus & Metrics

Academic Career Length

21Years (2006-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 December 2010 in Brazilian Journal of Microbiology
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Journal Article
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LRLaura Beatriz Rodrigues
Laura Beatriz Rodrigues
LSLuciana Ruschel dos Santos
Luciana Ruschel dos Santos
VTVinícius Zancanaro Tagliari
Vinícius Zancanaro Tagliari
NRNatalie Nadin Rizzo
Natalie Nadin Rizzo
GTGraciela Trenhago
Graciela Trenhago
VNVladimir Pinheiro Do Nascimento
Vladimir Pinheiro Do Nascimento
This study assessed biofilm formation on polystyrene by Staphylococcus aureus, Listeria monocytogenes, L. welshimeri and Escherichia coli, isolated from a slaughtering plant, grown on tryptic soy broth (TSB) using different glucose concentrations. The tested bacteria produced biofilm in at least one of the concentrations used, and some of them were strong biofilm producers.

31 January 2020 in The Journal of Infection in Developing Countries
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KBKaren Apellanis Borges
Karen Apellanis Borges
ICIsabel C Cisco
Isabel C Cisco
TFThales Quedi Furian
Thales Quedi Furian
DTDenise C Tedesco
Denise C Tedesco
LRLaura Beatriz Rodrigues
Laura Beatriz Rodrigues
Luciana Ruschel dos SantosLuciana Ruschel dos Santos
Luciana Ruschel dos Santos
Introduction: Campylobacteriosis is considered the most common bacteria-caused human gastroenteritis in the world. Poultry is a major reservoir of Campylobacter. Human infection may occur by consumption of raw and undercooked poultry or by contamination of other foods by these items. The aim of this study was to assess the prevalence of Campylobacter spp. in poultry processing plants with conventional culture method and real-time PCR. Methodology: A total of 108 poultry processing plant samples were collected to test with conventional microbiology and qPCR. Sampling included cloacal swabs, swabs of transport crates (before and after the cleaning and disinfection process) and carcasses (after the chiller, cooled at 4°C and frozen at −12°C). Results: Positivity in cloacal swabs indicated that poultry arrived contaminated at the slaughterhouse. Contamination in transport cages was substantially increased after the cleaning process, indicating that the process was ineffective. The detection of Campylobacter on carcasses was higher than that on cloacal swabs, which could indicate cross-contamination during the slaughtering process. Conventional microbiology and molecular methods revealed a prevalence of 69.4% and 43.5%, respectively. Lower detection by qPCR can be attributed to the high specificity of the kit and to biological components that could inhibit PCR reactions. Conclusions: Our results indicate that poultry arrive contaminated at the slaughterhouse and that contamination can increase during the slaughtering process due to cross-contamination. The isolation of Campylobacter in cooled and frozen carcasses corroborates the bacterial survival even at temperatures considered limiting to bacterial growth which are routinely used for food preservation.

1 October 2010 in Revista Brasileira de Engenharia Agrícola E Ambiental
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FSFabiano G. dos Santos
Fabiano G. dos Santos
PEPedro A. V. Escosteguy
Pedro A. V. Escosteguy
LRLaura Beatriz Rodrigues
Laura Beatriz Rodrigues
Neste trabalho se avaliou a qualidade de compostos de esterco de ave poedeira produzidos em pilhas de compostagem e se testaram os seguintes tratamentos: 1) sem gesso e sem revolvimento; 2) com gesso e sem revolvimento; 3) sem gesso e com revolvimento e 4) com gesso e com revolvimento. Para avaliar a qualidade dos compostos foram considerados os padrões do Ministério de Agricultura, Pecuária e Abastecimento (MAPA), estabelecidos para ovos e larvas de helmintos, Salmonella sp, coliformes totais e fecais, Cd, Cr, Ni, Pb, Se, C, N, umidade, relações C:N, C:CTC (Capacidade de troca de cátions) e pH. Os compostos obtidos nas pilhas revolvidas atenderam aos padrões de qualidade, exceto o teor de C, que foi menor. Nos compostos das pilhas com gesso e não revolvidas, o teor deste elemento excedeu o mínimo exigido mas os valores de N, de ovos de helmintos e de umidade, não corresponderam ao padrão do MAPA. Os teores de metais e de Se dos compostos foram menores que o máximo permitido, exceto o de Cd, cujo teor foi elevado no esterco utilizado nas pilhas sem gesso. Este aditivo decresceu o valor do pH dos compostos e aumentou o teor de N das pilhas não revolvidas. Em relação a todos os atributos avaliados, os melhores compostos foram obtidos nas pilhas revolvidas.

16 January 2016 in Acta Scientiae Veterinariae
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Journal Article
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LMLigiani Mion
Ligiani Mion
LPLuana Parizotto
Luana Parizotto
LSLilian Andriva dos Santos
Lilian Andriva dos Santos
BWBruna Webber
Bruna Webber
ICIsabel Cristina Cisco
Isabel Cristina Cisco
LSLuciana Ruschel dos Santos
Luciana Ruschel dos Santos
Background: Salmonella spp. are frequently isolated from fowls, and their detection in poultry products varies according to the breeding system and the slaughtering process, bringing risks to the consumer and compromising the marketability. The control of Salmonella in poultry slaughterhouses is based on the detection of bacteria, but the quantification of the agent would be important in assessing risk, as well as in obtaining data to determine the capacity of each step of the process to decrease or increase bacterial contamination. The aims of this study were to propose a method for the quantification of Salmonella in poultry slaughterhouses, frequency of isolation and serovars identified.Materials, Methods & Results: Twenty-one broiler flocks from seven federally inspected slaughterhouses in southern Brazil, totaling 1,071 samples, were assessed by miniaturized most probable number (mMPN) and conventional microbiology. The samples were collected in triplicate at 17 points, which included cloacae, transportation cages before and after sanitization, water (scald tank, supply, pre-chiller and chiller), and carcasses (before and after scalding, defeathering, rinsing, evisceration, final rinsing, chilling at 4ºC, and freezing at -12°C for 24 h, 30 and 60 days). Typical Salmonella colonies were submitted to TSI, LIA, SIM, urea, and polyvalent anti-O antiserum tests, and to final identification by Microarray by Check&Trace. Nine of the 1,071 (0.83%) samples analyzed by mMPN and by conventional microbiology were positive for Salmonella and the following serovars were identified: Anatum, Brandenburg, Agona, Tennessee, Bredeney, Schwarzengrund and Infantis.Discussion: This positive rate was lower than that described by other authors, whose rates ranged from 3% and 39% for the isolation of Salmonella spp. from different sources, such as slaughterhouses and retail sales in samples collected in Brazil. The low frequency of isolation of Salmonella in this study can be attributed to the efficiency of control systems used from the field to the slaughterhouse, such as Good Manufacturing Practices (GMP) and Sanitation Standard Operating Procedures (SSOP), which are HACCP requirements. Also, when slaughtering technology actions are properly managed, such as water replacement and temperatures lower than 4ºC in the chiller, the initial contamination by Salmonella spp. can be reduced, with a decline in contamination from 70% to 20%, and with a reduction in the contamination of broiler carcasses after chilling from 15.8% to 3.3%. On the other hand the contamination of carcasses by Salmonella before pre-chilling and in post-chilling might be due to the automated system, inadequate temperatures during chilling, and inappropriate water chlorination in the assessed meat-packing plant. Of the 17 points evaluated, seven were positive for Salmonella, especially the cages after sanitization and frozen carcasses. The contamination by Salmonella spp. in transportation cages after sanitization indicates inefficiency of the automated system as well as possible bacterial resistance to the sanitizers used in SSOP while the isolation in carcasses frozen for 24 h and 60 days demonstrates the thermal resistance of the bacterium to a conservation method widely used in the food industry. In this work, just one of the nine positive samples for Salmonella was identified by conventional methods (CM) and mMPN. The discrepancy between methods can be explained by the heterogeneous distribution of Salmonella and other bacteria in naturally contaminated samples. Samples that were positive in the qualitative test but negative in the mMPN protocol could have had a number of Salmonella below the detection amount.

18 April 2018 in Acta Scientiae Veterinariae
Verified
Journal Article
Open access
LRLaura Beatriz Rodrigues
Laura Beatriz Rodrigues
LSLuciana Ruchel Dos Santos
Luciana Ruchel Dos Santos
NRNatalie Nadin Rizzo
Natalie Nadin Rizzo
DFDaiane Ferreira
Daiane Ferreira
AOAmauri Picollo De Oliveira
Amauri Picollo De Oliveira
Vladimir Pinheiro do NascimentoVladimir Pinheiro do Nascimento
Vladimir Pinheiro do Nascimento
Background: The hygiene procedures in poultry slaughterhouses consist in the use of hot water, detergent and sanitizing, configuring Sanitation Standard Operating Procedure (SSOP). These actions control contamination in food processing environments, especially by pathogenic microorganisms, which cause diseases with impact on public health and economic losses. The microbiological control of aerobic mesophiles, Staphylococcus aureus and Escherichia coli, are used as indica­tors of contamination. The hygienic-sanitary conditions on the surfaces of the poultry slaughterhouse cuttting room were evaluated, before and after cleaning and sanitizing procedures.Materials, Methods & Results: Conventional microbiology (Rodac plates and sponge for quantification of aerobic me­sophiles, Staphylococcus aureus and Escherichia coli) and ATP-Bioluminescence were used to analyze the action of hot water and the active principles peracetic acid, quaternary ammonia and biguanide in the standard pre-operational hygiene procedure in the cutting room of the poultry slaughterhouse under Federal Inspection with slaughter capacity of more than 20.000 birds/h. The evaluations were performed on three lines of chicken thigh cuts at the same time and in a completely randomized manner on stainless steel surfaces, polyurethane belts and polyethylene boards. Samples were made in four replicates at the three surface totaling 108 assay for each microorganism. The samples were collected at the end of the cut­ting process, before and after washing the surfaces with hot water (between 45 and 50ºC) and after sanitization with 0.5% peracetic acid, 2% quaternary ammonia and 1% biguanide. The ATP-Bioluminescence method detected organic matter at all collected points and Rodac plates allowed a better recovery of microorganisms than sponges for quantification of aerobic mesophiles, E. coli and S. aureus. There was a reduction of contamination after the action of hot water and, after using quaternary ammonia and peracetic acid, there was no isolation of E. coli and S. aureus on all evaluated surfaces.Discussion: The use of different methods of analysis for monitoring the hygiene and sanitary status of contact surfaces with chicken cuts allows greater flexibility in relation to hygiene control. The use of the bioluminescent ATP detection method allows detecting in seconds extremely low levels of contamination, allowing a quick determination of the cleaning efficiency on the surfaces and evaluation of the hygiene programs. Conventional microbiology methods, on the other hand, provide indicators of contamination by different microorganisms on food contact surfaces. Both are applicable in SSOP monitor­ing programs and sanitary conditions of the contact surfaces in food producing establishments. The significant reduction of microorganisms on surfaces after cleaning, found in this study, demonstrates the importance of operational hygiene in the maintenance of microbial contamination below...

23 June 2010 in Ciência Animal Brasileira
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Luciana Ruschel dos SantosLuciana Ruschel dos Santos
Luciana Ruschel dos Santos
JNJoão Francisco Scalco Neto
João Francisco Scalco Neto
NRNatalie Nadin Rizzo
Natalie Nadin Rizzo
PBPaulo Vinícius Bastiani
Paulo Vinícius Bastiani
LRLaura Beatriz Rodrigues
Laura Beatriz Rodrigues
MBMaurício Veloso Brun
Maurício Veloso Brun
Resumo Avaliou-se a contaminação ambiental no Hospital Veterinário da Universidade de Passo Fundo (HV-UPF) e realizaram-se testes de eficiência de desinfetantes e antibiogramas com as bactérias isoladas. A contaminação ambiental foi inferior à recomendação da APHA de 30 ufc/cm2 (sedimentação simples) e 2 ufc/cm2 (swabs), mas isolaram-se Staphylococcus aureus, S. epidermidis, Pseudomonas aeruginosa, Escherichia coli, Enterobacter agglomerans e Arcanobacterium pyogenes. Os princípios ativos testados foram álcool 70%, amônia quaternária 3,5% e hipoclorito de sódio. O hipoclorito mostrou-se ineficaz contra as bactérias testadas, o álcool 70% foi ineficaz contra a E. aglomerans e S. epidermidis com trinta segundos de contato e a amônia quaternária 3,5% foi ineficaz contra a E.coli nos tempos de trinta segundos, um e cinco minutos e a P. aeruginosa após trinta segundos de contato. No teste de sensibilidade a antimicrobianos, 100% dos S. epidermidis foram resistentes à penicilina G, à oxacilina e ao cloranfenicol; 66,6% à ciprofloxacina, à cefepime e à rifamicina B, e 33,3% à eritromicina, ao sulfametoxazol+trimetoprim e à gentamicina. Já o TSA das demais bactérias isoladas revelou multirresistência. A contaminação ambiental no HV-UPF foi diminuída a níveis aceitáveis com os procedimentos de higienização adotados, mas isolaram-se do ambiente hospitalar bactérias patogênicas e com potencial de multirresistência. PALAVRAS-CHAVES: Antibiograma, desinfetantes, veterinária.