Research in veterinary science最新文献

{"title":"Diagnostic evaluation of a recombinant chimeric Sporothrix brasiliensis protein-based ELISA for serological detection of feline sporotrichosis","authors":"Débora Matilde de Almeida ,&nbsp;Laura de Vargas Maiocchi ,&nbsp;Natasha Rodrigues de Oliveira ,&nbsp;Camila Moura de Lima ,&nbsp;Martha Bravo Cruz Piñeiro ,&nbsp;Gabriela Ladeira Sanzo ,&nbsp;Tatiélen Hernandez Severo ,&nbsp;Odir Antonio Dellagostin ,&nbsp;Marcia de Oliveira Nobre ,&nbsp;Sérgio Jorge","doi":"10.1016/j.rvsc.2026.106059","DOIUrl":"10.1016/j.rvsc.2026.106059","url":null,"abstract":"<div><div>Sporotrichosis is a zoonotic infection caused by fungi of the <em>Sporothrix schenkii</em> complex, with <em>S. brasiliensis</em> being the most prevalent etiological agent in animals, particularly cats. Felines are highly susceptible to infection and may develop severe clinical forms characterized by extensive cutaneous lesions and systemic dissemination. In addition, infected cats play a major role in zoonotic transmission, as <em>Sporothrix</em> spp. can be transmitted to humans through bites and scratches. The gold standard for sporotrichosis diagnosis remains the isolation and identification of <em>Sporothrix</em> species from clinical samples, a process that requires prolonged culture prior to identification. However, the increasing number of cases highlights the need for a reliable, rapid, and cost-effective diagnostic method. This study aimed to develop an indirect enzyme-linked immunosorbent assay (ELISA) for the serodiagnosis of feline sporotrichosis using a recombinant chimeric <em>S. brasiliensis</em> protein. The antigen was designed from immunogenic fragments of two <em>S. brasiliensis</em> proteins, SsEno and Gp70, and expressed in a prokaryotic system. A total of 201 feline serum samples were analyzed, including 66 from cats diagnosed with sporotrichosis, 73 from healthy animals, and 62 from cats with other medical conditions. The assay demonstrated 97.0% sensitivity (95% CI: 89.4–99.6%) and 94.1% specificity (95% CI: 88.6%–97.4%). The recombinant chimeric antigen showed strong reactivity with sera from infected cats and no cross-reactivity with controls samples. These results indicate that this recombinant antigen-based ELISA is a simple, accurate, and low-cost diagnostic alternative with promising potential for validation and routine application in the diagnosis of feline sporotrichosis.</div></div>","PeriodicalId":21083,"journal":{"name":"Research in veterinary science","volume":"201 ","pages":"Article 106059"},"PeriodicalIF":1.8,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145979204","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Q fever in the 21st century: Uncovering diagnostic, epidemiological, and one health gaps in a re-emerging zoonosis","authors":"Foluke Olajumoke Jemilehin ,&nbsp;Adelekan Oluseyi Okunlade ,&nbsp;Ridwan Olamilekan Adesola ,&nbsp;Happiness Chibuzo Obiechefu ,&nbsp;Akeem Olayiwola Ahmed","doi":"10.1016/j.rvsc.2026.106060","DOIUrl":"10.1016/j.rvsc.2026.106060","url":null,"abstract":"<div><div>Q fever, caused by the gram negative obligate intracellular bacterium <em>Coxiella burnetii</em>, remains a globally relevant but underappreciated zoonosis in the 21st century. Despite decades of research, the disease continues to pose diagnostic, epidemiological, and clinical challenges that hinder timely recognition and effective management. This review aims to synthesize current advances in the epidemiology, pathogenesis, and diagnosis of <em>C. burnetii</em>, while critically examining the One Health gaps that sustain its persistence as a re-emerging zoonosis. We evaluate the strengths and limitations of existing diagnostic platforms, summarize recent progress in molecular epidemiology, and explore the underrecognized contributions of environmental and wildlife reservoirs to transmission. We further highlight disparities in surveillance and reporting, particularly in regions such as Africa and Asia, where the disease remains neglected. Looking ahead, we outline key priorities for research and practice. These include elucidating molecular mechanisms of host–pathogen interactions, identifying novel diagnostic biomarkers, deploying genomic epidemiology to capture global strain diversity, developing safer and more accessible vaccines, and operationalizing One Health frameworks to integrate veterinary, medical, and environmental surveillance. By clarifying these research and policy gaps, this review provides a roadmap for reducing the global burden of Q fever and offers broader insights into tackling other neglected zoonotic diseases at the human–animal–environment interface.</div></div>","PeriodicalId":21083,"journal":{"name":"Research in veterinary science","volume":"201 ","pages":"Article 106060"},"PeriodicalIF":1.8,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145966827","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dietary nano‑chromium picolinate enhances interferon-gamma expression in heat-stressed broilers vaccinated against Newcastle disease","authors":"Farhad Hajializadeh ,&nbsp;Alireza Talebi ,&nbsp;Raziallah Jafari Jozani","doi":"10.1016/j.rvsc.2025.106044","DOIUrl":"10.1016/j.rvsc.2025.106044","url":null,"abstract":"<div><div>Poultry immunity is negatively impacted by heat stress (HS), resulting in reduced efficacy of vaccines. In this study, we determined whether dietary chromium (III) picolinate (CrPic) and the nano formulation (Nano-CrPic) could help alleviate the negative effects of HS on cellular immunity in vaccinated broilers against Newcastle disease (ND). Ross 308 broilers were subjected to continuing heat exposure and received supplementations of either CrPic or Nano-CrPic at 500, 1000, or 1500 ppb. Following ND vaccination, we quantified the expression of IFN-γ mRNA from splenic tissues. Importantly, IFN-γ expression increased between about 2.5–4 fold in vaccinated versus control broilers at 3 days after vaccination. In addition, under HS conditions, Nano-CrPic at 500 and 1000 ppb increased IFN-γ expression by 35–50 % compared to broilers in the HS Controls (<em>p</em> &lt; 0.01) and 20–30 % compared to broilers fed traditional CrPic at comparable levels of supplementation. On the other hand, no significant change in IFN-γ expression was observed following either CrPic or Nano-CrPic supplementation in non-vaccinated birds. Supplementation with Nano-CrPic at the highest-level of 1500 ppb had diminished enhancements on IFN-γ expression, suggesting a non-linear dose-response pattern. The findings indicate that dietary supplementation using Nano-CrPic at 500–1000 ppb provides a practical means of improving cellular immunity responses that are generated after vaccination, particularly in heat-stressed broilers, thereby improving potential vaccination response under heat stress.</div></div>","PeriodicalId":21083,"journal":{"name":"Research in veterinary science","volume":"200 ","pages":"Article 106044"},"PeriodicalIF":1.8,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145864842","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bacterially expressed non-glycosylated recombinant bovine interferon lambda demonstrates antiviral activity against bovine viral diarrhea virus in cell culture","authors":"David J. Holthausen ,&nbsp;Kathryn A. Bickel ,&nbsp;Gisselle N. Medina ,&nbsp;Daniel W. Nielsen ,&nbsp;Bryan S. Kaplan ,&nbsp;Eduardo Casas ,&nbsp;Rohana P. Dassanayake","doi":"10.1016/j.rvsc.2026.106071","DOIUrl":"10.1016/j.rvsc.2026.106071","url":null,"abstract":"<div><div>Bovine viral diarrhea virus (BVDV) is a pathogen of economic concern for the cattle industry due to reproductive losses, persistently infected animals, and for contributing to the bovine respiratory disease complex. Bovine interferon lambda 3 (IFN-λ3) is a type III interferon and a glycosylated cytokine with potent antiviral activity. The recombinant glycosylated bovine IFN-λ3 (rbIFN-λ3) has antiviral activity against BVDV in Madin-Darby bovine kidney (MDBK) cells. Bacterial expression systems provide a higher-yield and more cost-effective alternative to eukaryotic expression systems. The antiviral properties of bacterially expressed non-glycosylated rbIFN-λ3 against BVDV in cell culture was determined in this study. The coding sequence for the mature bovine IFN-λ3 was cloned into a bacterial expression vector and non-glycosylated rbIFN-λ3 was expressed and purified. Cells were pre-treated with serial dilutions of rbIFN-λ3 one day prior to infection with BVDV. The rbIFN-λ3 treatment was repeated daily, and viral infection status was assessed three days post-infection using immunohistochemistry with a monoclonal antibody specific to the BVDV E2 glycoprotein. A single band corresponding to non-glycosylated rbIFN-λ3 with the expected molecular mass was observed on SDS-PAGE, and the identity of rbIFN-λ3 was confirmed <em>via</em> western blotting. Our results indicated that bacterially expressed rbIFN-λ3 without glycosylation demonstrated concentration-dependent antiviral activity, effectively reducing BVDV replication. These results indicate that glycosylation is not required for the antiviral function of bovine IFN-λ3, and supports the potential of using bacterially expressed, non-glycosylated bovine IFN-λ3 in antiviral therapies against BVDV infections.</div></div>","PeriodicalId":21083,"journal":{"name":"Research in veterinary science","volume":"201 ","pages":"Article 106071"},"PeriodicalIF":1.8,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145979202","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Wild UK deer as carriers of livestock lameness associated pathogens","authors":"Simon R. Clegg ,&nbsp;Andrew S. Cooke ,&nbsp;Elektra Poluha ,&nbsp;Stefan H. Millson ,&nbsp;Joseph W. Angell ,&nbsp;Nicholas J. Evans","doi":"10.1016/j.rvsc.2025.106042","DOIUrl":"10.1016/j.rvsc.2025.106042","url":null,"abstract":"<div><div>Lameness is one of the major diseases on UK farms and worldwide and can be caused by environmental damage and/or infection. The pathogens associated with infectious lameness, namely <em>Fusobacterium necrophorum</em>, <em>Dichelobacter nodosus</em> and pathogenic <em>Treponema</em> species are responsible for substantial economic losses. The lack of knowledge on reservoirs of these pathogens is concerning and wild deer may pose a potential risk for livestock infection. This study investigated the prevalence of lameness associated bacteria on the feet of culled wild deer using molecular methods and subsequent isolation to characterise bacteria and allow comparison to livestock pathogens. With the exception of <em>Treponema medium</em>, all the other pathogens were detected on deer feet with sika deer carrying the fewest pathogens and muntjac and roe carrying the most. Muntjac deer were significantly more likely than other deer species to carry <em>F. necrophorum</em>. Body condition score was a significant factor associated with pathogen carriage, with a higher body condition score leading to lower pathogen carriage. Identical treponemes based on 16S rRNA genes were isolated to those found in cattle and sheep. The assessment of the antimicrobials which the <em>Treponema</em> isolates were susceptible to, showed a high similarity to those previously reported in livestock, thus further suggesting carriage of similar bacteria. This study shows that wild deer within the UK are carriers for lameness bacteria but are asymptomatic. The infection risk which these wild ruminant ungulates pose to livestock species requires further research. This study begins to suggest a potential wildlife reservoir for lameness associated bacteria.</div></div>","PeriodicalId":21083,"journal":{"name":"Research in veterinary science","volume":"200 ","pages":"Article 106042"},"PeriodicalIF":1.8,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145878884","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Emergence of a novel subgenotype 2.4 of classical swine fever virus in India","authors":"Sharanagouda Shiddanagouda Patil ,&nbsp;Jayaramareddy Harish ,&nbsp;Kothapete Ramakrishna Ganesh,&nbsp;Kuralayanapalya Puttahonnappa Suresh,&nbsp;Jagadish Hiremath,&nbsp;Shivasharanappa Nayakvadi","doi":"10.1016/j.rvsc.2025.106031","DOIUrl":"10.1016/j.rvsc.2025.106031","url":null,"abstract":"<div><div>Classical Swine Fever Virus (CSFV) remains a major constraint to pig production worldwide, despite vaccination and control efforts. This study investigated the genetic diversity, phylogeography, and population structure of CSFV using E2 gene sequences from 53 Indian isolates spanning 18 states and union territories and 85 global isolates from 28 countries. Phylogenetic analysis revealed that Indian CSFV strains predominantly belong to genotype 2, with subgenotype 2.2 as the dominant and widely distributed lineage across India, reflecting long-term endemic circulation. Subgenotype 2.4, restricted mainly to Northeast India, clustered closely with Southeast Asian strains, suggesting regional evolution and transboundary transmission, while subgenotype 1.1 persisted as an older lineage alongside genotype 2 viruses. Global analysis demonstrated extensive genetic structuring, with genotype 2 exhibiting the highest diversity and broader geographic spread compared to other genotypes. Haplotype analysis identified high haplotype diversity in both Indian (Hd = 0.9853) and global (Hd = 0.9871) datasets, characterized by numerous region-specific haplotypes and limited shared haplotypes indicative of localized evolution punctuated by occasional long-distance dissemination. Shared haplotypes among Indian states and between countries highlight the role of animal movement and trade in CSFV spread. Overall, the combined phylogenetic and population genetic analyses underscore the complex evolutionary dynamics of CSFV in India and globally, emphasizing the need for continuous molecular surveillance and region-specific control.</div></div>","PeriodicalId":21083,"journal":{"name":"Research in veterinary science","volume":"200 ","pages":"Article 106031"},"PeriodicalIF":1.8,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145820538","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development and evaluation of recombinant protective antigen (rPA)-based indirect-ELISA for sero-monitoring of anthrax-specific antibodies in sheep","authors":"Sripada Sairam ,&nbsp;Roopa Anandamurthy Hemanth ,&nbsp;Suresh Bindu ,&nbsp;Mandrira Ramakrishna Namrutha ,&nbsp;Anand Shirisha ,&nbsp;Pillenahalli Sadashivappa Pooja ,&nbsp;Awadhesh Prajapati ,&nbsp;Revanaiah Yogisharadhya ,&nbsp;Nihar Nalini Mohanty ,&nbsp;Sandeep Kumar Singh ,&nbsp;Mohammed Mudassar Chanda ,&nbsp;Sathish Bhadravati Shivachandra","doi":"10.1016/j.rvsc.2026.106058","DOIUrl":"10.1016/j.rvsc.2026.106058","url":null,"abstract":"<div><div>Protective antigen (PA), a key exotoxin of <em>Bacillus anthracis</em>, is involved in the pathogenesis of anthrax, leading to ‘sudden death’ of affected herbivores. PA is also known to induce protective neutralizing antibodies following vaccination. Although an effective anthrax live spore vaccine is used to immunize susceptible animals, pre- and post-vaccination antibody titres are not regularly monitored, which is of immunological significance in endemic areas, and it is important to evaluate the vaccine efficacy at the field level. Hence, this study describes a standardized indirect-ELISA, a simple and rapid immuno-assay based on recombinant protective antigen (603 aa, ∼67 kDa) to detect anti-PA-specific IgG antibodies in sheep serum samples to assess serological evidence of exposure and/or vaccination to anthrax. Further, rPA-iELISA was used to assess prevailing antibody titers in randomly collected sheep (<em>n</em> = 1289) serum samples from three different states representing anthrax-endemic (Telangana) and non-endemic (Punjab and Haryana) geographical regions of India. A standardized rPA antigen (200 ng/well) based indirect-ELISA was found to possess an area under the curve (AUC) of 0.980 and 95 % CI of 0.932–0.992 with sensitivity of 93.7 %, and specificity of 94.9 % (<em>p</em> &lt; 0.001) against an optimal cut-off criterion of &gt;25.3 PP (&gt;0.46 OD). A higher degree of sero-positivity in Telangana (&gt;66.98 %), and a lower positivity was noted in Punjab and Haryana (6.83 % and 15.95 %, respectively) among sheep. The study indicated the potential utility of rPA-iELISA for sero-monitoring of anthrax / anti-PA-specific IgG antibodies in sheep.</div></div>","PeriodicalId":21083,"journal":{"name":"Research in veterinary science","volume":"201 ","pages":"Article 106058"},"PeriodicalIF":1.8,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145940803","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluating attitudes toward piglet euthanasia among Spanish-speaking animal caretakers on U.S. commercial swine farms: A comparison of CO₂ and non-penetrating captive bolt methods","authors":"Brooke Kitting ,&nbsp;Faby Hernandez ,&nbsp;Pablo Lamino ,&nbsp;John J. McGlone ,&nbsp;Heidi Villalba ,&nbsp;Allen Jimena Martinez Aguiriano ,&nbsp;Miguel Alejandro Hernandez Corrales ,&nbsp;Daniela Sofia Lima Alvarez ,&nbsp;Arlene Garcia","doi":"10.1016/j.rvsc.2025.106023","DOIUrl":"10.1016/j.rvsc.2025.106023","url":null,"abstract":"<div><div>The use of a non-penetrating captive bolt (NPCB) gun to euthanize suckling pigs may be visually challenging and stressful to animal caretakers, influencing their ability to make timely euthanasia decisions. The objective of this study was to utilize a survey to characterize the emotional and practical challenges of Spanish-speaking animal caretakers (<em>n</em> = 257) employed on commercial swine farms in the United States, as they transitioned from carbon dioxide (CO₂) gas euthanasia to NPCB as the primary method of euthanasia in suckling piglets. The survey results indicated concerns primarily centered on perceived inhumaneness and potential pain inflicted on piglets, particularly with the NPCB method. Caretakers expressed concerns about the psychological impact of CO₂, but felt it was a more humane alternative than NPCB. Male caretakers were less likely than females to dislike euthanizing piglets (<em>p</em> = 0.013). Animal caretakers who were aware of the Common Swine Industry Audit (CSIA; <em>p</em> = 0.010), animal caretakers with a college degree (<em>p</em> &lt; 0.05), and those who decided when to euthanize an animal and conducted the procedure themselves preferred to have someone else perform the task of euthanasia (<em>p</em> &lt; 0.01). These findings highlight how demographics and knowledge of the CSIA influence animal caretakers' decisions and preferences regarding piglet euthanasia. These findings also emphasize a challenge with animal caretakers' reluctance to accept science-based animal welfare practices.</div></div>","PeriodicalId":21083,"journal":{"name":"Research in veterinary science","volume":"200 ","pages":"Article 106023"},"PeriodicalIF":1.8,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145792140","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Active transmission of Crimean-Congo Hemorrhagic fever virus, a tick-borne disease, in Iraq: Animal host population movement dynamics and retrospective case study analysis (2018–2023)","authors":"Khalis Ahmed Hammad Ameen ,&nbsp;Ameen Saleh Alyousuf ,&nbsp;Blesa Abdulhameed Salh ,&nbsp;Hiro Mohammed Obaid ,&nbsp;Ihab Raqeeb Aakef","doi":"10.1016/j.rvsc.2025.106021","DOIUrl":"10.1016/j.rvsc.2025.106021","url":null,"abstract":"<div><div>This study is a retrospective and descriptive cross-sectional analysis examining demographic and epidemiological data of Crimean-Congo Hemorrhagic Fever Virus (CCHFV) in Iraq, covering confirmed cases from January 2018 to December 2023. Utilizing data from the Iraq CDC/zoonotic department, 1001 cases were analyzed and confirmed via Real-time PCR and ELISA tests at the Central Public Health Laboratory. The study highlights the climatic conditions of Iraq, with its semi-arid and semi-tropical climate influencing disease prevalence. Results indicate a significant gender disparity in CCHFV cases, with 59.4 % male and 40.6 % female patients, suggesting differing exposure and susceptibility between genders. The age distribution shows higher infection rates among individuals aged 22 to 51, potentially linked to occupational exposure and outdoor activities. A notable increase in reported cases was observed in 2022 and 2023, accounting for 38.0 % and 58.6 % of total cases, respectively. This surge may be attributed to environmental and socio-economic factors, including climate change, urbanization, and population displacement.</div><div>Geographic analysis reveals that provinces like Thiqar, Baghdad, Basra, and Misan report higher case numbers, indicating regional hotspots for CCHFV transmission. Risk factor analysis emphasizes the role of direct contact with raw meat, animal slaughtering, and tick bites as significant contributors to infection. The study also identifies key symptoms associated with poor prognosis, such as bleeding from injection sites, body orifices, and echymosis, which are significantly correlated with higher mortality rates. These findings underscore the need for targeted public health interventions, including enhanced surveillance, vector control, and public education, particularly in high-risk regions. Understanding the epidemiology and risk factors of CCHFV is crucial for developing effective prevention and control strategies to mitigate the impact of this disease in Iraq.</div></div>","PeriodicalId":21083,"journal":{"name":"Research in veterinary science","volume":"200 ","pages":"Article 106021"},"PeriodicalIF":1.8,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145792138","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Antimicrobial resistance and virulence-associated genes in Escherichia coli from young healthy chickens","authors":"Giulia Cagnoli ,&nbsp;Fabrizio Bertelloni ,&nbsp;Flavia Zendri ,&nbsp;Dorina Timofte ,&nbsp;Alessia Di Paolo ,&nbsp;Margherita Marzoni Fecia di Cossato ,&nbsp;Valentina Virginia Ebani","doi":"10.1016/j.rvsc.2026.106062","DOIUrl":"10.1016/j.rvsc.2026.106062","url":null,"abstract":"<div><div><em>Escherichia coli</em> is a commensal intestinal bacterium of humans and animals and is frequently associated with antimicrobial resistance (AMR). This study investigated the phenotypic and genotypic AMR and virulence factors in <em>E. coli</em> isolated from 120 young healthy chickens never treated with antibiotics and coccidiostats. The disk diffusion method employed on all 120 isolates revealed the highest resistance (11.67%) to chloramphenicol and trimethoprim-sulfamethoxazole. All isolates were susceptible to aztreonam and gentamicin, whereas over 95% showed susceptibility to amikacin, cefoxitin, ciprofloxacin, and ertapenem. Minimum inhibition concentration test found 7 (5.83%) isolates resistant to colistin. Eight strains (6.67%) were found to be multidrug-resistant (MDR). Molecular analyses conducted on resistant and intermediate isolates showed that 11/13 penicillin-resistant strains carried the <em>blaTEM</em> gene, 12/12 tetracycline-resistant strains had <em>tet</em>A, 4/14 chloramphenicol-resistant and 1/2 chloramphenicol-intermediate strains had <em>cmlA</em>. The <em>astA</em> gene, potentially indicative of enteroaggregative <em>E. coli</em> (EAEC), was found in 15% of isolates. Virulence genes characterizing other pathotypes investigated were not detected. Chickens reared in optimal conditions and never treated with antibiotics may harbor antimicrobial-resistant and pathogenic bacterial strains that could become a public health hazard. Good farm management and hygiene are fundamental to reducing the circulation of pathogenic strains and the need for antimicrobial treatments.</div></div>","PeriodicalId":21083,"journal":{"name":"Research in veterinary science","volume":"201 ","pages":"Article 106062"},"PeriodicalIF":1.8,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145966820","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}