This study aimed to evaluate the effect of a pectin biofilm on the preservation of refrigerated and unrefrigerated eggs during 5 wk of storage based on egg weight loss, albumen height, Haugh unit (HU), and the yolk index (YI). A total of 1,200 nonfertile eggs from GLK Bankiva laying hens (40 wk of age), which were freshly laid and came from a single collection, were obtained from a model poultry rearing system (Planaltina, Federal District, Brazil) that meets all animal welfare criteria. The experimental outline was entirely randomized, with 20 treatments in a factorial scheme of 2 × 2 × 5, with 2 biofilm treatments (with and without) × 2 storage temperatures (refrigeration: 5°C and ambient: 25°C) × 5 storage periods (7, 14, 21, 28, and 35 d), with 12 repetitions per treatment. Starting from the third storage week, increased weight loss (%) was observed in noncoated eggs (4.46 ± 1.06; 5.61 ± 1.37; 6.93 ± 1.66%) compared with biofilm-coated eggs (3.57 ± 1.26; 4.74 ± 1.8; 6.05 ± 2.21%), respectively. The HU variation in the pectin-coated eggs (86.84-78.02) was smaller than that in the noncoated eggs (83.01-64.36) between the beginning (7 d) and the end (35 d) of the experimental period. Eggs with and without biofilm stored in the refrigerator presented average HU values of 91.26 ± 6.27 and 88.35 ± 6.96, respectively. In contrast, when kept at room temperature, eggs with the coating presented higher HU values (71.27 ± 10.78) than eggs without the coating (59.11 ± 15.97). Coated eggs (0.37 ± 0.16) showed higher YI values than noncoated eggs (0.35 ± 0.16). A pectin-based biofilm effectively maintained egg quality during the 35 d of storage.

Listeria monocytogenesandSalmonellaspp. are considered important foodborne pathogens that are commonly associated with foods of animal origin. The aim of this study was to perform molecular characterization ofL.monocytogenesandSalmonellaspp. isolated from biofilms of cattle and poultry slaughterhouses located in the Federal District and State of Goiás, Brazil. FourteenL.monocytogenesisolates and oneSalmonellasp. were detected in poultry slaughterhouses. No isolates were detected in cattle slaughterhouses. AllL.monocytogenesisolates belonged to lineage II, and 11 different pulsotypes were detected. Pulsed-field gel electrophoresis analysis revealed the dissemination of two strains within one plant, in addition to the regional dissemination of one of them. TheSalmonellaisolate was identified via whole genome sequencing asSalmonella entericaserovar Minnesota ST548. In the sequence analysis, no premature stop codons were detected in theinlAgene ofListeria. All isolates demonstrated the ability to adhere to Caco-2 cells, while 50% were capable of invading them. Antimicrobial resistance was detected in 57.1% of theL.monocytogenesisolates, and resistance to sulfonamide was the most common feature. ThetetC,ermB, andtetMgenes were detected, and four isolates were classified as multidrug-resistant.Salmonellasp. was resistant to nine antimicrobials and was classified as multidrug-resistant. Resistance genesqnrB19,bla_CMY-2,aac(6’)-Iaa,sul2, andtetA, and a mutation in theparCgene were detected. The majority (78.5%) of theL.monocytogenesisolates were capable of forming biofilms after incubation at 37°C for 24 h, and 64.3% were capable of forming biofilms after incubation at 12°C for 168 h. There was no statistical difference in the biofilm-forming capacity under the different evaluated conditions.Salmonellasp. was capable of forming biofilms at both tested temperatures. Biofilm characterization was confirmed by collecting the samples consistently, at the same sampling points, and by assessing biofilm formationin vitro. These results highlight the potential risk of cross-contamination in poultry slaughterhouses and the importance of surveillance and pathogen control maintenance programs within the meat production industry.

This study aimed to verify the presence ofListeria monocytogenes,Salmonellaspp., andEscherichia coliin two Brazilian swine slaughterhouses, as well as to perform antibiograms, detect virulence and antimicrobial resistance genes, and evaluate thein vitrobiofilm-forming capability of bacterial isolates from these environments. OneSalmonellaTyphi isolate and 21E.coliisolates were detected, whileL.monocytogeneswas not detected.S. Typhi was isolated from the carcass cooling chamber’s floor, resistant to several antimicrobials, including nalidixic acid, cefazolin, chloramphenicol, doxycycline, streptomycin, gentamicin, tetracycline, and sulfonamide, and contained resistance genes, such astet(B),tet(C),tet(M), andampC. It also showed moderate biofilm-forming capacity at 37°C after incubating for 72 h. The prevalence of the 21E.coliisolates was also the highest on the carcass cooling chamber floor (three of the four samplings [75%]). TheE.coliisolates were resistant to 12 of the 13 tested antimicrobials, and none showed sensitivity to chloramphenicol, an antimicrobial prohibited in animal feed since 2003 in Brazil. The resistance genesMCR-1,MCR-3,sul1,ampC,clmA,cat1,tet(A),tet(B), andblaSHV, as well as the virulence genesstx-1,hlyA,eae,tir α,tir β,tir γ, andsaawere detected in theE.coliisolates. Moreover, 5 (23.8%) and 15 (71.4%)E.coliisolates presented strong and moderate biofilm-forming capacity, respectively. In general, the biofilm-forming capacity increased after incubating for 72 h at 10°C. The biofilm-forming capacity was the lowest after incubating for 24 h at 37°C. Due to the presence of resistance and virulence genes, multi-antimicrobial resistance, and biofilm-forming capacity, the results of this study suggest a risk to the public health as these pathogens are associated with foodborne diseases, which emphasizes the hazard of resistance gene propagation in the environment.

O objetivo deste trabalho foi realizar o isolamento e analisar o perfil de resistência antimicrobiana de Enterococcus de carcaças de frango resfriadas e congeladas comercializadas no Distrito Federal, detectando genes de resistência antimicrobiana e identificando as espécies Enterococcus faecalis e Enterococcus faecium por reação polimerase em cadeia. Foram analisadas 100 carcaças de frangos, das quais foram isoladas 50 cepas de Enterococcus spp., sendo 42% de E. faecalis e 2% de E. faecium. O teste de susceptibilidade antimicrobiana demonstrou que todas as cepas isoladas apresentaram resistência a pelo menos um antimicrobiano, dos quais 90,47% das cepas de E. faecalis, 100% das cepas de E. Faecium e 82,14% dos Enterococcus spp. apresentaram resistência à Tetraciclina; 80,95% das cepas de E. faecalis e 35,71% das cepas de Enterococcus spp. foram resistentes à Eritromicina; 39,28% dos Enterococcus spp. e 23,80% dos E. faecalis à Ciprofloxacina e 28,57% dos E. faecalis apresentaram resistência ao Cloranfenicol. Foram detectados os genes de resistência antimicrobiana erm(B), vanC-1, aph(3')-llla, ant(6)-la, vanB, vanA, aac(6')-le-aph(2'')-la, erm(A) e tet(M) - este último mais frequente. Estes resultados sugerem sérios problemas para a Saúde Pública, uma vez que esses microrganismos podem possuir a capacidade de transmitir genes de resistência antimicrobiana para outros microrganismos presentes na microbiota intestinal de humanos e animais, podendo inviabilizar o uso destas drogas para tratamentos clínicos.

This study aimed to count Enterobacteriaceae and Escherichia coli in different locations on pig carcasses (shank, loin, abdomen, shoulder, and jowl) from two slaughterhouses (A and B) between September 2019 and July 2021 during different slaughter stages (after bleeding, after passing through the epilator machine, after manual toileting in the dirty area, before and after evisceration, and after the final washing), as well as verify antimicrobial resistance and biofilm formation capacity. The main points of Enterobacteriaceae and E. coli contamination were identified in the two slaughterhouses through three collections. The stages with the highest counts were post-bleeding and evisceration in both slaughterhouses and after manual toileting in slaughterhouse B in the first collection. Most E. coli isolates were resistant to multiple antimicrobials, with higher resistance frequencies to amoxicillin, ampicillin, chloramphenicol, sulfonamides, and streptomycin. The virulence genes eae, stx1, and stx2 were also detected. Three isolates had all three genes and exhibited resistance to at least six antimicrobial classes (β-lactams, macrolides, aminoglycosides, sulfonamides, amphenicols, and quinolones). E. coli isolates also showed a high frequency of strains with moderate and strong in vitro biofilm-forming capacity. This is the first study to characterize microbial contamination by pig slaughter stage in the Federal District region, demonstrating the critical points for hygienic production. E. coli was isolated from the surface of pig carcasses, as well as the virulence genes stx1, stx2, and eae were detected. The multi-antimicrobial resistant isolates also had a moderate-to-strong biofilm formation capacity, thus demonstrating risks to public health.

Listeria monocytogenes é um patógeno relevante veiculado por alimentos. Sua identificação precisa é importante para a correta determinação do risco associado à ingestão do alimento. O objetivo deste trabalho foi verificar a ocorrência das espécies de Listeria spp. em amostras de salsichas tipo hot dog e carne moída bovina, comercializadas a granel no Distrito Federal. Foram analisadas 162 amostras, sendo 127 de salsichas tipo hot dog e 35 amostras de carne moída bovina. O isolamento e a identificação do gênero foram feitos por metodologia convencional e a distinção das espécies foi verificada por kit bioquímico específico (API-Listeria®) e por análise de restrição de fragmentos da reação em cadeia da polimerase (RFLP-PCR) do gene 23 rRNA. Foram isoladas 26 cepas de Listeria spp. das amostras de salsichas tipo hot dog, sendo identificadas 18 cepas de Listeria innocua e 08 cepas de Listeria monocytogenes. Das 35 amostras de carne moída bovina, foram isoladas 16 cepas de Listeria spp., sendo identificadas 12 cepas de Listeria innocua e 04 de Listeria monocytogenes. Houve concordância total na distinção das espécies de Listeria spp. através dos dois métodos empregados. A presença de Listeria spp. em amostras de salsicha do tipo hot dog a granel e em carne moída bovina a granel, de estabelecimentos comerciais do Distrito Federal, representa risco à saúde do consumidor.