Antimicrobial susceptibility, biofilm formation and genetic profiles of Escherichia coli isolated from retail chicken meat.

Brazil is the number one exporter of chicken meat, and this industry maintains constant microbiological vigilance. The objective of this study was to characterize the pathogenicity, antimicrobial resistance (AMR) and the profile of biofilm production of Escherchia coli strains isolated from raw refrigerated cuts of chicken meat sold in retail markets of the four largest poultry companies in Brazil. We collected 150 samples of chicken meat, in order to isolate E. coli and performed susceptibility tests (to amoxicillin associated with clavulanic acid, ceftiofur, enrofloxacin, gentamicin, and trimethoprim + sulfamethoxazole). In addition, the disc approximation test to detect extended spectrum beta-lactamases enzymes (ESBLs) producers was performed. E. coli ability to form biofilm was checked using polystyrene microplates. We also searched for ESBLs genes (blaCTY-M2, blaSHV-1, blaTEM-1, blaCTX-M2, blaOXA-1, blaPSE-1 and AmpC) and adhesion genes (sfa/foc, afa/draB, iha, hrla, fimC, tsh, papC, mat, cr1, felA, fimH and papG) in ESBL-E. coli producers and in those E. coli classified as strongly biofilm formers, respectively. The overall percentage of E. coli isolation was 58.66%, with brand A having the highest percentage (70%), followed by brands D, B and C (60, 53.3 and 50%, respectively). The highest resistance profile was observed for beta-lactams (39.5%), followed by sulfonamide associated to trimethoprim (36.9%) and polymyxin (33.4%). Of the isolates obtained, 77% were non-susceptible to at least one antimicrobial. Brand A showed the highest overall percentage of resistance with 95.23%, followed by brands C (80%), B (75%) and D (69.44%). Overall, 73.86% of the isolates were non susceptible to at least one antibiotic and 36.3% were multiresistants. A total of 17.04% of E. coli strains were identified as ESBLs producers and 70.44% were able to form biofilms (moderate-to-strong). The blaTEM-1 gene was the most prevalent (73.33%), followed by blaSHV-1 (46.66%) and blaCMY-2 (6%). Of the 31 strongly biofilm-forming strains, 26 (83.87%), 24 (77.41%) and 20 (64.51%) expressed fimC, papG and crl genes, respectively. Taken together, our results show that Brazilian chicken meat can be contaminated with E. coli that are non-susceptible to multiple antibiotics, able to form biofilm and showing a diverse repertoire of adhesins linked to pathogenicity depending on the brand evaluated.

Mineralization in newborn calves contributes to health, improve the antioxidant system and reduces bacterial infections.

The first phase of life of dairy calves has elevated mortality indices linked with low immunity and sanitary challenges, mainly bacterial infections are involved in the pathogenesis of diarrhea, the leading cause of death. Also, other important problem is the nutritional deficiencies, such as the mineral deficiency. Thus, the aim of this study was to evaluate whether an intramuscular mineral supplementation based on selenium, copper, potassium, magnesium and phosphorus possess beneficial effects on health of dairy calves. For this, ten calves were divided in two groups: the group A was supplemented with injectable mineral, while the group B was used as control group (without mineral supplementation). The mineral complex was administrated via intramuscularly at dose of 3 mL/animal on days 2 and 14 post-birth. The total blood was collected on days 2, 10, 20 and 30 of life of animals in order to analyze the antioxidant enzymes (catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GPx)), blood count and seric biochemistry linked with proteic, lipid and carbohydrate metabolism. Feces samples were also collected on days 10, 20 and 30 of life of animals to perform the total bacterial count, parasitological exam and fecal consistency score. Moreover, the weight and corporal temperature were also evaluated. The mineral supplementation presented beneficial properties to calves from birth to the 30th of life through the increase on activity of antioxidant enzymes, improvement of immunity, and avoiding problems linked with diarrhea and anemia, can be considered an interesting approach to prevent these alterations linked with high mortality in the period of life.