Resistance and Virulence Surveillance in Escherichia coli Isolated from Commercial Meat Samples: A One Health Approach.

Escherichia coli is a key indicator of food hygiene, and its monitoring in meat samples points to the potential presence of antimicrobial-resistant strains capable of causing infections in humans, encompassing resistance profiles categorized as serious threats by the Centers for Disease Control and Prevention (CDC), such as Extended-Spectrum Beta-Lactamase (ESBL)-a problem with consequences for animal, human, and environmental health. The objective of the present work was to isolate and characterize ESBL-producing E. coli strains from poultry, pork, and beef meat samples, with a characterization of their virulence and antimicrobial resistance profiles. A total of 450 meat samples (150 chicken, 150 beef, and 150 pork) were obtained from supermarkets and subsequently cultured in medium supplemented with cefotaxime. The isolated colonies were characterized biochemically, followed by antibiogram testing using the disk diffusion technique. Further classification involved biofilm formation and the presence of antimicrobial resistance genes (blaCTX-M, AmpC-type, mcr-1, and fosA3), and virulence genes (eaeA, st, bfpA, lt, stx1, stx2, aggR, iss, ompT, hlyF, iutA, iroN, fyuA, cvaC, and hylA). Statistical analysis was performed via the likelihood-ratio test. In total, 168 strains were obtained, with 73% originating from chicken, 22% from pork, and 17% from beef samples. Notably, strains exhibited greater resistance to tetracycline (51%), ciprofloxacin (46%), and fosfomycin (38%), apart from ß-lactams. The detection of antimicrobial resistance in food-isolated strains is noteworthy, underscoring the significance of antimicrobial resistance as a global concern. More than 90% of the strains were biofilm producers, and strains carrying many ExPEC genes were more likely to be biofilm formers (OR 2.42), which increases the problem since the microorganisms have a greater chance of environment persistence and genetic exchange. Regarding molecular characterization, bovine samples showed a higher prevalence of blaCTX-M-1 (OR 6.52), while chicken strains were more likely to carry the fosA3 gene (OR 2.43, CI 1.17-5.05) and presented between 6 to 8 ExPEC genes (OR 2.5, CI 1.33-5.01) compared to other meat samples. Concerning diarrheagenic E. coli genes, two strains harbored eae. It is important to highlight these strains, as they exhibited both biofilm-forming capacities and multidrug resistance (MDR), potentially enabling colonization in diverse environments and causing infections. In conclusion, this study underscores the presence of ß-lactamase-producing E. coli strains, mainly in poultry samples, compared to beef and pork samples. Furthermore, all meat sample strains exhibited many virulence-associated extraintestinal genes, with some strains harboring diarrheagenic E. coli (DEC) genes.

Peritonitis and necrotizing hepatitis in Ara ararauna caused by a foreign body

Background: The ingestion of foreign bodies in parrots has already been described and associated with the curious behaviorof the birds or with stressful conditions. Foreign bodies in the gastrointestinal tract are usually diagnosed through clinicalsigns, laboratory tests, and radiographic findings in the historical data. Foreign bodies are usually metallic and can lodgein any segment of the gastrointestinal tract, commonly found in the proventricle and gizzard. This study investigated acase of necrotizing hepatitis due to a foreign body in Ara ararauna (Linnaeus, 1758).Case: An approximately 9-month-old specimen of caninde macaw, had sudden death and was referred for autopsy. Themacroscopic examination revealed a fibrous, thick, reddish membrane involving the left hepatic lobe and partially the gizzard in continuity with the peritoneum. Inside the capsule, the liver had a friable and necrotic appearance and the gizzardhad a focal perforation area containing a foreign body (gavage tube feeding). We performed the histopathological examination of the liver and gizzard and observed that the membrane surrounding the liver and partially the gizzard had a chronicinflammatory process with a marked proliferation of fibrous tissue and fibrin deposition. The hepatic parenchyma of theleft lobe showed diffuse and marked necrosis, with signs of ischemic necrosis. In the region of transmural perforation ofthe gizzard, the mucosa showed a focal area of extensive necrosis accompanied by the presence of intralesional bacteria.The lesions observed are attributed to the perforation of the organs by the foreign body. It is not known whether the birdingested the object accidently during food handling as a young or due to the curious behavior of the bird or even the stressit may have been exposed to. The post mortem examination revealed localized peritonitis...(AU)

Peritonitis and necrotizing hepatitis in Ara ararauna caused by a foreign body

Background: The ingestion of foreign bodies in parrots has already been described and associated with the curious behaviorof the birds or with stressful conditions. Foreign bodies in the gastrointestinal tract are usually diagnosed through clinicalsigns, laboratory tests, and radiographic findings in the historical data. Foreign bodies are usually metallic and can lodgein any segment of the gastrointestinal tract, commonly found in the proventricle and gizzard. This study investigated acase of necrotizing hepatitis due to a foreign body in Ara ararauna (Linnaeus, 1758).Case: An approximately 9-month-old specimen of caninde macaw, had sudden death and was referred for autopsy. Themacroscopic examination revealed a fibrous, thick, reddish membrane involving the left hepatic lobe and partially the gizzard in continuity with the peritoneum. Inside the capsule, the liver had a friable and necrotic appearance and the gizzardhad a focal perforation area containing a foreign body (gavage tube feeding). We performed the histopathological examination of the liver and gizzard and observed that the membrane surrounding the liver and partially the gizzard had a chronicinflammatory process with a marked proliferation of fibrous tissue and fibrin deposition. The hepatic parenchyma of theleft lobe showed diffuse and marked necrosis, with signs of ischemic necrosis. In the region of transmural perforation ofthe gizzard, the mucosa showed a focal area of extensive necrosis accompanied by the presence of intralesional bacteria.The lesions observed are attributed to the perforation of the organs by the foreign body. It is not known whether the birdingested the object accidently during food handling as a young or due to the curious behavior of the bird or even the stressit may have been exposed to. The post mortem examination revealed localized peritonitis...

Salmonelose em bezerros pelo sorovar Dublin no estado do Paraná, Brasil - aspectos clínico-patológicos / Salmonellosis in calves by serovar Dublin in Paraná State, Brazil - clinicopathological aspects

Background: Calf diarrhea remains one of the main diseases affecting the cattle industry. Persistence of this significant problem is associated with the complexity of factors that may be involved (infectious, environmental). An accurate diagnosis is essential for confirming the cause and helping clinicians and cattle producers to apply appropriate strategies in a timely manner. This report describes the histological changes according to the degree of salmonellosis severity, which is a contagious infectious disease caused by Salmonella enterica subsp. enterica, a Gram-negative bacterium, in two beef calves in northern Paraná State, southern Brazil. Cases: Two 90-day-old crossbred Angus and Nellore calves from a beef farm in northern Paraná State were referred to a Veterinary Hospital. Animal 1- developed acute clinical signs (enteritis, ataxia, and muscle rigidity) and died the day after the signs began. Gross findings included heavy and non-collapsed lungs, pulmonary oedema, hepatomegaly, enteritis, and severe diffuse typhlitis. Microscopic analysis revealed severe diffuse necrotic enteritis, typhlitis, severe diffuse interstitial pneumonia, moderate centrilobular hepatic necrosis, mild multifocal nephritis, and severe spleen and lymph node necrosis. Paratyphoid nodules were evidenced on the liver, spleen, and mesenteric lymph nodes. Animal 2- presented apathy, green fibrinous diarrhea, and died three days after the onset of clinical signs. The macroscopic examination showed moderate diffuse enteritis and hepatosplenomegaly. At the microscopic examination, many paratyphoid nodules were observed on the liver, spleen, kidneys, and Peyer's patches, which were associated with intralesional and intravascular bacilli. Additional findings included severe diffuse fibrinous necrotic enteritis with intralesional bacilli, diffuse interstitial pneumonia, multifocal splenic necrosis, lymphoid depletion, and moderate multifocal to coalescent lymphocytic nephritis. Histological Gram staining was performed on selected samples, revealing intralesional Gram-negative bacilli in the liver and intestine. Thus, liver and intestine fragments were used for the microbiological examination. Microbiological culture, isolation and biochemical tests identified the genus Salmonella spp. Then, the colonies were subjected to serological tests for serovar identification, according to ISO/TR 6579-3, which determined the serovar Dublin. After identifying the disease etiological agent, the outbreak was controlled by appropriate antibiotic therapy combined with the correction of sanitary measures. Discussion: Enteritis is a frequent disease in calves, posing a diagnostic challenge in identifying the etiological agent. In the present case, the histological, microbiological, and serological results confirmed a disseminated Salmonella spp. infection. The microscopic findings, such as interstitial pneumonia, fibrinous necrotic enteritis markedly in ileum and paratyphoid nodules in various organs, are the most common aspects of the disease. However, fibrinous cholecystitis, which is considered pathognomonic for salmonellosis, was not observed in this study. Therefore, the absence of such a lesion should not exclude the disease in sick animals. A microscopic injury score was used to determine lesion severity by assigning values from 1 to 4, wherein: 1 = no apparent lesions, 2 = mild lesions, 3 = moderate lesions, and 4 = severe lesions. Both calves were scored as 4. Multiple predisposing factors for the condition were identified in this farm such as different age animals in the same paddock and no specific paddock for sick animals, given that the infectious agent remains in feces, saliva, and nasal discharge. The serovar Dublin induces several clinical signs such as septicemic, respiratory, and enteric manifestations, making a clinical diagnosis a challenge