{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,18]],"date-time":"2026-03-18T20:46:47Z","timestamp":1773866807296,"version":"3.50.1"},"reference-count":1,"publisher":"Polish Academy of Sciences Chancellery","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"abstract":"<jats:p>Neonatal calf diarrhoea caused by Escherichia coli (E. coli) pathotypes remains a major health concern in livestock. This study aimed to characterise E. coli pathotypes isolated from diarrhoeic calves in the K\u00fc\u00e7\u00fck Menderes Basin, T\u00fcrkiye, and to evaluate their antimicrobial resistance profiles. Faecal samples were collected from 100 calves across five districts. Twentyfive E. coli isolates were obtained and analysed by PCR for virulence genes. Antimicrobial susceptibility was tested using the disk diffusion method, following guidelines from the Clinical and Laboratory Standards Institute (CLSI). Enterotoxigenic E. coli (ETEC) was the most prevalent pathotype (64%). Multiple virulence gene combinations were detected, including one isolate (4%) that carried virulence genes associated with ETEC, enterohaemorrhagic E. coli (EHEC), and enteropathogenic E. coli (EPEC). Antimicrobial susceptibility testing revealed high effectiveness of florfenicol (80%) and tetracycline (76%), while resistance was highest to penicillin G (88%), streptomycin (52%), and aztreonam (64%). Multidrug resistance (MDR), defined as phenotypic resistance to three or more antimicrobial classes, was observed in 36% (9\/25) of the isolates. The high prevalence of ETEC confirms its dominant role in neonatal calf diarrhoea, whereas substantial \u03b2-lactam resistance underscores the need for prudent antibiotic use and regionally adapted management strategies.<\/jats:p>","DOI":"10.24425\/pjvs.2026.158512","type":"journal-article","created":{"date-parts":[[2026,3,18]],"date-time":"2026-03-18T13:02:00Z","timestamp":1773838920000},"page":"111-111","source":"Crossref","is-referenced-by-count":0,"title":["Prevalence of virulent Escherichia coli pathotypes in calf diarrhoea: molecular characterisation and antibiotic resistance profiles in T\u00fcrkiye"],"prefix":"10.24425","author":[{"given":"V.","family":"\u00d6zavci","sequence":"first","affiliation":[{"name":"Dokuz Eyl\u00fcl University, Faculty of Veterinary Medicine, Department of Microbiology, Dokuzcesmeler Campus, Adatepe Mahallesi, 24 Sokak No: 2, 35400 Buca, Izmir, T\u00fcrkiye"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"\u015e.","family":"Kirkan","sequence":"additional","affiliation":[{"name":"Aydin Adnan Menderes University, Faculty of Veterinary Medicine, Department of Microbiology, Isikli Campus, 09016 Aydin, T\u00fcrkiye"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"H.T.","family":"Y\u00fcksel Dolgun","sequence":"additional","affiliation":[{"name":"Aydin Adnan Menderes University, Faculty of Veterinary Medicine, Department of Microbiology, Isikli Campus, 09016 Aydin, T\u00fcrkiye"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"E.","family":"Karada\u015f","sequence":"additional","affiliation":[{"name":"Dokuz Eyl\u00fcl University, Faculty of Veterinary Medicine, Department of Pathology, Dokuzcesmeler Campus, Adatepe Mahallesi, 24 Sokak No: 2, 35400 Buca, Izmir, T\u00fcrkiye"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Y.","family":"Sefero\u011flu","sequence":"additional","affiliation":[{"name":"Aydin Adnan Menderes University, Faculty of Veterinary Medicine, Department of Microbiology, Isikli Campus, 09016 Aydin, T\u00fcrkiye"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"37468","published-online":{"date-parts":[[2026,3,17]]},"reference":[{"key":"ref0","unstructured":"Aarestrup FM (1999) Association between the consumption of antimicrobial agents in animal husbandry and the occurrence of resistant bacteria among food animals. Int J Antimicrob Agents 12: 279-285. Akane AE, Tessema TS, Ali DA (2022) Distribution of E. coli biotypes shed by dairy calves in selected dairy farms in Bishoftu, Ethiopia. Ethiop Vet J 26: 132-142. Akyuz E, Naseri A, Erkilic EE, Makav M, Uzlu E, Kirmizigul AH, Gokce G (2017) Neonatal calf diarrhoea and sepsis. Kafkas Univ Vet Fak Derg 10: 181-191. Astorga F, Navarrete-Talloni MJ, Mir\u00f3 MP, Bravo V, Toro M, Blondel CJ, Herv\u00e9-Claude LP (2019) Antimicrobial resistance in E. coli isolated from dairy calves and bedding material. Heliyon 5: e02773. Awad WS, El-Sayed AA, Mohammed FF, Bakry NM, Abdou NMI, Kamel MS (2020) Molecular characterization of pathogenic Escherichia coli isolated from diarrheic and in-contact cattle and buffalo calves. Trop Anim Health Prod 52: 3173-3185. Ayd\u0131n F, Umur S, G\u00f6kce G, Genc O, G\u00fcler MA (2001) Isolation and identification of bacterial and parasitic agents from diarrheal calves in Kars district. Kafkas Univ Vet Fak Derg 7: 7-14. Blanco M, Blanco JE, Dahbi G, Mora A, Alonso MP, Varela G (2006) Typing of intimin (eae) genes from enteropathogenic Escherichia coli (EPEC) isolated from children with diarrhoea in Montevideo, Uruguay: identification of two novel intimin variants (muB and xiR\/beta2B). J Med Microbiol 55: 1165-1174. Bruyand M, Mariani-Kurkdjian P, Gouali M, de Valk H, King LA, Le Hello S, Bonacorsi S, Loirat C (2018) Hemolytic uremic syndrome due to Shiga toxin-producing Escherichia coli infection. Med Mal Infect 48: 167-174 Caneschi A, Bardhi A, Barbarossa A, Zaghini A (2023) The use of antibiotics and antimicrobial resistance in veterinary medicine, a complex phenomenon: a narrative review. Antibiotics 12: 487. Chandra M, Cheng P, Rondeau G, Porwollik S, McClelland M (2013) A single-step multiplex PCR for identification of six diarrheagenic E. coli pathotypes and Salmonella. Int J Med Microbiol 303: 210-216 Citil M, G\u00fcnes V, Karademir B (2003) A retrospective study on diarrheic calves brought to internal medicine clinic of KAU faculty of veterinary medicine between 1996 and 2001. Kafkas Univ Vet Fak Derg 9: 39-42. Clinical and Laboratory Standards Institute (CLSI) (2022) Performance standards for antimicrobial susceptibility testing. 32nd ed., CLSI, Wayne, PA. https:\/\/clsi.org\/about\/press-releases\/clsi-publishes-m100-performance-standardsfor-antimicrobial-susceptibility-testing-32nd-edition\/ Coskun A, Kaya U (2018) Determination of etiology of neonatal calves diarrhea in Tokat region. Manas J Agric Vet Life Sci 8: 75-80. De Verdier K, Nyman A, Greko C, Bengtsson B (2012) Antimicrobial resistance and virulence factors in Escherichia coli from Swedish dairy calves. Acta Vet Scand 54: 2. Duse A, Waller KP, Emanuelson U, Unnerstad HE, Persson Y, Bengtsson B (2015) Risk factors for antimicrobial resistance in fecal Escherichia coli from preweaned dairy calves. J Dairy Sci 98: 500-516. Emre Z, Alabay BM, Fidanci H, D\u00fczg\u00fcn A, Cerci H (1998) Prevalence of Cryptosporidium spp. Infection and its relation to other enteric pathogens (Escherichia coli K99 and rotavirus) in cattle in Ankara, Turkey. Turk J Vet Anim Sci 22: 453-457. Ferreira MR, Stella AE, Freitas-Filho EG, Silva TS, Nascimento KA, Pinto JF, Moreira CN (2018) Distribution of the stx1 and stx2 genes in Escherichia coli isolated from milk cattle according to season, age, and production scale in southwestern region of Goi\u00e1s, Brazil. Arq Bras Med Vet Zootec 70: 1807-1813. Fouad H, Saleh H, Elazazy H, Hamed A, Samir S (2022) Prevalence of pathogenic E. coli in diarrhoeic cattle calves and antibiotic resistance genes. Kafrelsheikh Vet Med J 20: 12-18. G\u00fcnes V, \u00dcnver A, Citil M, Citil HMM (2004) The Prevalence of Escherichia coli O157 Serotype and Clostridium Perfringens Type A a-toxin in Neonatal Diarrhoeic Calves in Kars District. Kafkas Univ Vet Fak Derg 10: 41-45. Hou X, Niu Z, Wu S, Du Q, Liu G, Nie L, Zhu C, Qiu Y, Huang Y, Cao Y, Tong D (2025) Dairy Cattle Infection with Bovine Rotavirus at Different Growth Stages and Its Impact on Health and Productivity.&nbsp;Animals&nbsp;15: 1628. Izzo MM, Kirkland PD, Mohler FL, Perkins NR, Gunn AA, House JK (2011) Prevalence of major enteric pathogens in Australian dairy calves with diarrhoea. Aust Vet J 89: 167-173. K\u00fclig CC, Coskun A (2019) Prevalence of E. coli, Cryptosporidium, Clostridium perfringens, Rotavirus and Coronavirus in neonatal calves with diarrhea in Sivas. Turk Vet J 1: 69-73. Kumar S, Suvidhi DK, Milind M, Bhati T (2022) Occurrence of E. coli and associated risk factors in neonatal calf diarrhea from Bikaner. Pharma Innov J 11: 1030-1033. Martinez JL, Baquero F (2002) Interactions among strategies associated with bacterial infection: pathogenicity, epidemicity, and antibiotic resistance. Clin Microbiol Rev 15: 647-679. Meganck V, Hoflack G, Opsomer G (2014) Advances in prevention and therapy of neonatal dairy calf diarrhoea: a systematic review with emphasis on colostrum management and fluid therapy. Acta Vet Scand 56: 75. M\u00fcller D, Greune L, Heusipp G, Karch H, Fruth A, Tsch\u00e4pe H, Schmidt MA (2007) Identification of unconventional intestinal pathogenic Escherichia coli isolates expressing intermediate virulence factor profiles using a novel singlestep multiplex PCR. Appl Environ Microbiol 73: 3380-3390. Nepomuceno LL, Maciel KA, Santos HD, Floresta AC, Baum C, Dias FE, Nepomuceno LC, Reis VR, Nascimento CA, Alexandrino B, Minharro S (2016) Antimicrobial susceptibility of Escherichia coli isolated from poultry. Acta Vet Bras 10: 1-8. https:\/\/api.semanticscholar.org\/CorpusID: 261601324. Nikkhah A, Alimirzaei M (2022) Colibacillosis and colisepeticemia in newborn calves: towards pragmatic treatment and prevention. World J Vet 12: 230-236. Picco NY, Alustiza FE, Bellingeri RV, Grosso MC, Motta CE, Larriestra AJ, Vissio C, Tiranti KI, Terzolo HR, Moreira AR, Vivas AB (2015) Molecular screening of pathogenic Escherichia coli strains isolated from dairy neonatal calves in Cordoba province, Argentina. Rev Argent Microbiol 47: 95-102. Shahrani M, Dehkordi FS, Momtaz H (2014) Characterisation of Escherichia coli virulence genes, pathotypes, and antibiotic resistance properties in diarrheic calves in Iran. Biol Res 47: 28. Stenutz R, Weintraub A, Widmalm G (2006) The structures of Escherichia coli O-polysaccharide antigens. FEMS Microbiol Rev 30: 382-403. Tutija JF, Ramos CA, Lemos RA, Santos AA, Reckziegel GH, Freitas MG, Leal CR (2022) Molecular and phenotypic characterization of Escherichia coli from calves in an important meat-producing region in Brazil. J Infect Dev Ctries 16: 1030-1036. Vidal M, Kruger E, Dur\u00e1n C, Lagos R, Levine M, Prado V, Toro C, Vidal R (2005) Single multiplex PCR assay to identify simultaneously the six categories of diarrheagenic Escherichia coli associated with enteric infections. J Clin Microbiol 43: 5362-5365. Younis EE, Ahmed AM, El-Khodery SA, Osman SA, El-Naker YF (2009) Molecular screening and risk factors of enterotoxigenic Escherichia coli and Salmonella spp. in diarrheic neonatal calves in Egypt. Res Vet Sci 87: 373-379. Yue S, Zhang Z, Liu Y, Zhou Y, Wu C, Huang W, Chen N, Zhu Z (2021) Phenotypic and molecular characterizations of multidrug-resistant diarrheagenic E. coli of calf origin. Anim Dis 1: 14."}],"container-title":["Polish Journal of Veterinary Sciences"],"original-title":[],"language":"pl","link":[{"URL":"https:\/\/journals.pan.pl\/Content\/138536\/12%20_%20Ozavci.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,3,18]],"date-time":"2026-03-18T13:27:09Z","timestamp":1773840429000},"score":1,"resource":{"primary":{"URL":"https:\/\/journals.pan.pl\/dlibra\/publication\/158512\/edition\/138536\/content"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,3,17]]},"references-count":1,"URL":"https:\/\/doi.org\/10.24425\/pjvs.2026.158512","relation":{},"ISSN":["1505-1773"],"issn-type":[{"value":"1505-1773","type":"print"}],"subject":[],"published":{"date-parts":[[2026,3,17]]}}}