RESUMO
This study aimed to investigate the impact of temperature and the presence of other microorganisms on the susceptibility of STEC to biocides. Mature biofilms were formed at both 10°C and 25°C. An inoculum of planktonic bacteria comprising 106 CFU/mL of spoilage bacteria and 103 CFU/mL of a single E. coli strain (O157, O111, O103, and O12) was used to form mixed biofilms. The following bacterial combinations were tested: T1: Carnobacterium piscicola + Lactobacillus bulgaricus + STEC, T2: Comamonas koreensis + Raoultella terrigena + STEC, and T3: Pseudomonas aeruginosa + C. koreensis + STEC. Tested biocides included quaternary ammonium compounds (Quats), sodium hypochlorite (Shypo), sodium hydroxide (SHyd), hydrogen peroxide (HyP), and BioDestroy®-organic peroxyacetic acid (PAA). Biocides were applied to 6-day-old biofilms. Minimum Bactericidal Concentrations (MBC) and Biofilm Eradication Concentrations (BEC) were determined. Planktonic cells and single-species biofilms exhibited greater susceptibility to sanitizers (p < 0.0001). Lactobacillus and Carnobacterium were more susceptible than the rest of the tested bacteria (p < 0.0001). Single species biofilms formed by E. coli O111, O121, O157, and O45 showed resistance (100%) to Shypo sanitizer (200 ppm) at 25°C. From the most effective to the least effective, sanitizer performance on single-species biofilms was PAA > Quats > HyP > SHyd > Shypo. In multi-species biofilms, spoilage bacteria within T1, T2, and T3 biofilms showed elevated resistance to SHyd (30%), followed by quats (23.25%), HyP (15.41%), SHypo (9.70%), and BioDestroy® (3.42%; p < 0.0001). Within T1, T2, and T3, the combined STEC strains exhibited superior survival to Quats (23.91%), followed by HyP (19.57%), SHypo (18.12%), SHyd (16.67%), and BioDestroy® (4.35%; p < 0.0001). O157:H7-R508 strains were less tolerant to Quats and Shypo when combined with T2 and T3 (p < 0.0001). O157:H7 and O103:H2 strains in mixed biofilms T1, T2, and T3 exhibited higher biocide resistance than the weak biofilm former, O145:H2 (p < 0.0001). The study shows that STEC within multi-species biofilms' are more tolerant to disinfectants.
RESUMO
Meat production is a complex system, continually receiving animals, water, air, and workers, all of which serve as carriers of bacteria. Selective pressures involved in different meat processing stages such as antimicrobial interventions and low temperatures, may promote the accumulation of certain residential microbiota in meat cutting facilities. Bacteria including human pathogens from all these sources can contaminate meat surfaces. While significant advancements have been made in enhancing hygienic standards and pathogen control measures in meat plants, resulting in a notable reduction in STEC recalls and clinical cases, STEC still stands as a predominant contributor to foodborne illnesses associated with beef and occasionally with pork. The second-and third-generation sequencing technology has become popular in microbiota related studies and provided a better image of the microbial community in the meat processing environments. In this article, we reviewed the potential factors influencing the microbial ecology in commercial meat processing facilities and conducted a meta-analysis on the microbiota data published in the last 10 years. In addition, the mechanisms by which bacteria persist in meat production environments have been discussed with a focus on the significant human pathogen E. coli O157:H7 and generic E. coli, an indicator often used for the hygienic condition in food production.
RESUMO
El objetivo de este estudio fue determinar patrones de resistencia y multirresistencia de cepas de Salmonella spp. Aisladas de una planta procesadora de aves, hacia las quinolonas y fluoroquinolonas (ácido nalidíxico=Na, ciprofloxacina=Cf y enrofloxacina= Ex), así como a otros antimicrobianos: tetraciclinas (T), oxitetraciclina (O), neomicina (N), nitrofurantoina (Nf), trimetoprim (Tr) y cloranfenicol (C). Un total de 146 aislamientos de Salmonella spp. fueron obtenidos de diferentes fuentes: 34 cepas provenientes de mezclas de vísceras blancas (colón, ciegos) y vísceras rojas (hígado y bazo); 87 cepas aisladas de las canales en los procesos de desplume, eviscerado, enfriamiento y empacado; 8 cepas obtenidas de subproductos comestibles (patas, cuellos, hígados y mollejas) y 19 cepas de muestras de ambientes (agua, hielo y superficies de equipos). Se utilizaron técnicas microbiológicas convencionales, pruebas bioquímicas, serológicas y pruebas de susceptibilidad a los antibióticos por difusión en agar. Los resultados revelaron una alta resistencia para Na (73,3 por ciento; 107/146), Nf (60,2 por ciento; 88/146), T (56,2 por ciento; 82/146), O (54,8 por ciento; 80/146), Tr (54,1 por ciento; 79/146) y una menor resistencia a Ex (6.2 por ciento; 9/146), Cf (2,7por ciento; 4/146), N (2,0 por ciento; 3/146) y C (2,5por ciento; 4/146). Se encontró un porcentaje elevado de multirresistencia (65,0 por ciento; 95/146) y dentro de ellos, los más notorios fueron: NaNfTTr (42,1 por ciento), NaNfTr (26,3 por ciento) y NaNfT (10,5 por ciento). No se observó relación significativa (P>0,05) entre los patrones de resistencia y multirresistencia encontrados con el origen de las diferentes cepas de Salmonella. Estos resultados evidencian el surgimiento de cepas de Salmonellas resistentes a las quinolonas y la necesidad de programas de vigilancia de resistencia antimicrobiana.
The aim of this study was to determine the resistance and multi-resistance patterns of strains of Salmonella spp. isolated in a poultry processing plant in Zulia State, to quinolones and fluoroquinolones (Nalidixic acid=Na, ciprofloxacin=Cf, and enrofloxacin=Ex), as well as other antimicrobial drugs: tetracycline (T), oxitetracycline (O), neomycin (N), nitrofurantoine (Nf), trimetropim (Tr) and chloranfenicol (C). A total of 146 Salmonella isolates were obtained from different sources: 34 strains from pools of Intestines (duodenal and colon) and internal organs (liver and spleen); 87 strains of carcass samples collected in four different phases: carcasses after defeathering, evisceration, chilling, and final packed products; 8 strains from edible by-products (neck, liver, gizzard and legs) and 19 strains from environmental samples (water, ice, and equipment surfaces). The detection analyses were performed using conventional microbiological techniques, biochemical tests, serological and agar diffusion methods for antimicrobial susceptibility. The results showed a high resistance to Na (73.3%; 107/146), Nf (60.2%; 88/147), T (56.2%; 82/146), O (54.8%; 80/146), Tr (54.1%; 79/146) and low resistance to Ex (6.2%; 9/146), Cf (2.7%; 4/146), N (2.0%; 3/146) and C (2.7%; 4/146). There was observed a high percentage of multi-resistant strains (65.0%; 95/146) and within of them, the most common patterns were: NaNfTTr (42.1%), NaNfTr (26.3%) and NaNfT (10.5%). No significant relationship was observed (P>0.05) between resistance and multi-resistance patterns with the source of the Salmonella strains. These results are evidence of the emergence of resistant Salmonella strains to fluoroquinolones and the necessity of programs for antimicrobial resistance surveillance.
Assuntos
Animais , Peptídeos Catiônicos Antimicrobianos , Galinhas/microbiologia , Quinolonas , Salmonella/isolamento & purificação , Vísceras , Reações Bioquímicas/métodos , Medicina VeterináriaRESUMO
En Venezuela, la incidencia de enfermedades respiratorias virales e inmunosupresoras son dos de los mayores problemas en la industria avícola nacional, y hasta el momento no se cuenta con suficiente información epidemiológica al respecto que ayude a establecer medidas de control, por lo que el objetivo de esta investigación fue determinar serológicamente la presencia de anemia infecciosa aviar, reovirus y gumboro, y su relación entre ellas, así como determinar el nivel de anemia en las aves evaluadas. Se tomaron muestras de aproximadamente 14 a 15 aves, de forma semanal a diferentes edades (1, 7, 14, 21, 28, 35 y 42 días), en tres granjas comerciales, tomándose un total de 295 aves. Los títulos de anticuerpos se midieron a través de la prueba ELISA, y el nivel de anemia, por la técnica de microhematocrito. Se detectaron porcentajes de anticuerpos séricos: 90,8 por ciento (268/295) para anemia infecciosa aviar; 82,4 por ciento (244/295) para reovirus y 97 por ciento (286/295) para la enfermedad infecciosa de la bursa. En cuanto a los valores de hematocrito se encontró en forma general que, el 19,6 por ciento (58/295) de las aves evaluadas presentaron anemia, mostrando valores de hematocrito entre 20 y 27 por ciento. Se observó una correlación positiva altamente significativa entre la anemia infecciosa aviar y los otros virus inmunosupresores estudiados, con gumboro (r=0,437; P<0,0001) y reovirus (r=0,312; P<0,0001). Los resultados obtenidos en este trabajo permiten demostrar la presencia del virus de la anemia infecciosa aviar en pollos de engorde en la región, de manera aislada o asociada con reovirus y gumboro, que pudiesen estar afectando en forma subclínica o clínica las granjas avícolas zulianas.
The incidence of viral respiratory and immunosuppressant diseases are two of the biggest problems in the Venezuelan poultry industry, however in the country, there is not enough epidemiological information that helps to establish control measures. The aim of this research was to determine the presence of serological chicken anemia virus, reovirus and gumboro, and it´s correlation between them as well as to determine the level of anemia in the evaluated birds. In this research, approximately fourteen or fifteen (14 or 15) birds were tested weekly and at different ages (1; 7; 14; 21; 28; 35 y 42 days), in three commercial farms. The samples were taken from a total of 295 birds. The viral antibodies were determined by ELISA test and the anemia levels by micro-hematocrit. The presence of seropositivity was 90.8% (268/295) for the chicken anemia virus, 82.4% (244/295) for reovirus and 97% (286/295) for gumboro. Of the total, 9.6% (58/295) of the evaluated birds presented anemia, showing values of hematocrits between 20% and 27%. A positive correlation was found between chicken anemia virus and the other immunosuppressor viruses studied, gumboro (r=0.437; P<0.0001) and reovirus (r=0.312; P<0.0001). The obtained results in this research demonstrated the presence of viral anemia, in broilers, in the Zulia Region, with or without the presence of reovirus and/or gumboro. That could have an effect, in either sub-clinical or clinical forms.