Molecular screening and risk factors of enterotoxigenic Escherichia coli and Salmonella spp. in diarrheic neonatal calves in Egypt

Department of Internal Medicine and Infectious Diseases, Faculty of Veterinary Medicine, Mansoura University, Mansoura 35516, Egypt.
Research in Veterinary Science (Impact Factor: 1.41). 05/2009; 87(3):373-9. DOI: 10.1016/j.rvsc.2009.04.006
Source: PubMed


The aim of the present study was to carry out molecular epidemiological investigation on enterotoxigenic Escherichia coli (ETEC) K99 and Salmonella spp. in diarrheic neonatal calves. Fecal samples were obtained from 220 diarrheic calves at 9 farms related to four governorates in central and northern Egypt. E. coli and Salmonella spp. isolates were examined for E. coli K99 and Salmonella spp. using PCR. ETEC K99 was recovered from 20 (10.36 %) out of 193 isolates, whereas Salmonella spp. was recovered from nine calves (4.09%). Multivariable logistic regression was used to evaluate the risk factors associated with both infections. ETEC K99 was significantly affected by age (P<0.01; OR: 1.812; CI 95%: 0.566-1.769), colostrum feeding practice (P<0.01; OR: 5.525; CI 95%: 2.025-15.076), rotavirus infection (P<0.001; OR: 2.220; CI 95%: 0.273-1.251), vaccination of pregnant dams with combined vaccine against rotavirus, coronavirus and E. coli (K99) (P<0.001; OR: 4.753; CI 95%: 2.124-10.641), and vitamin E and selenium administration to the pregnant dam (P<0.01; OR: 3.933; CI 95%: 0.703-1.248). Infection with Salmonella spp. was found to be significantly affected by the animal age (P<0.05; OR: 0.376; CI 95%: 0.511-1.369), Hygiene (P<0.05; OR: 0.628; CI 95%: 1.729-5.612), and region (P<0. 01; OR: 0.970; CI 95%: 0.841-1.624). The results of the present study indicate the importance of PCR as rapid, effective and reliable tool for screening of ETEC and Salmonella spp. when confronted with cases of undifferentiated calf diarrhea. Moreover, identification of the risk factors associated with the spreading of bacteria causing diarrhea may be helpful for construction of suitable methods for prevention and control.

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Available from: Sabry El-khodery, Jul 18, 2015
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    • "Serotypes Agona, Enteritidis, and S. enterica subsp. Enterica were isolated from fecal samples in the present study and in other studies (Ambrosin et al. 2002; Younis et al. 2009; Cummings et al. 2009a, b). In our study, the low number of animals infected and the serotypes detected, added the fact that no other enteric pathogen investigated was identified in animals infected with Salmonella spp., may explain why salmonellosis was not associated with diarrhea. "
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    ABSTRACT: This prospective longitudinal study investigated the epidemiology of enteric disease associated with infections in calves aging up to 70 days. A total of 850 fecal samples were collected from 67 calves. Seventeen isolates of Salmonella spp. were recovered from feces of 11 calves (16.4 %), and statistical analysis revealed no association between the presence of Salmonella spp. and clinical signs of diarrhea or age. Virulence factors of Escherichia coli were identified in 103 strains: eae (7), K99/STa (7), Stx1 (7), Stx1/eae (36), Stx1/Stx2/eae (2), Stx2 (43), and Stx2/eae (1). There was statistical association between diarrheic animals carrying E. coli Stx1/eae + in their feces at 2 and 4 weeks of age (P = 0.003) and E. coli Stx2 + at 5 weeks of age (P = 0.03). Rotavirus was detected in 49 (5.76 %) fecal samples collected from 33 calves (49.2 %). The presence of rotavirus was correlated with diarrheic feces (P < 0.0001) rather than feces with normal consistency. There was a significant relationship between age group and diarrhea (P = 0.001). Bovine coronavirus (BCoV) was detected in 93 fecal samples collected from 46 calves (68.6 %). There was an association (P < 0.0001) between diarrheic animals positive for BCoV and age groups. The results demonstrate the importance of the pathogens studied in the etiology of diarrhea in calves.
    Full-text · Article · Sep 2014 · Tropical Animal Health and Production
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    • "To the best of our knowledge, this is the first and most comprehensive report on serogroups, pathotypes, virulence genes and antimicrobial resistance properties in E. coli strains isolated from diarrheic calves in Iran. Totally, the prevalence of E. coli strains isolated from calves with diarrhea in Iran (76.45%, our results) was significantly higher than Egypt (10.36%) [37] and India (42.65%). Mora et al. [38] reported that 12% of the calves and 22% of the farms samples were positive for highly virulent STEC serotype O157:H7. "
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    ABSTRACT: Background Calf diarrhea is a major economic concern in bovine industry all around the world. This study was carried out in order to investigate distribution of virulence genes, pathotypes, serogroups and antibiotic resistance properties of Escherichia coli isolated from diarrheic calves. Results Totally, 76.45% of 824 diarrheic fecal samples collected from Isfahan, Chaharmahal, Fars and Khuzestan provinces, Iran were positive for E. coli and all of them were also positive for cnf2, hlyA, cdtIII, f17c, lt, st, stx1, eae, ehly, stx2 and cnf1 virulence genes. Chaharmahal had the highest prevalence of STEC (84.61%), while Isfahan had the lowest (71.95%). E. coli serogroups had the highest frequency in 1–7 days old calves and winter season. Distribution of ETEC, EHEC, AEEC and NTEC pathotypes among E. coli isolates were 28.41%, 5.07%, 29.52% and 3.49%, respectively. Statistical analyses were significant for presence of bacteria between various seasons and ages. All isolates had the high resistance to penicillin (100%), streptomycin (98.25%) and tetracycline (98.09%) antibiotics. The most commonly detected resistance genes were aadA1, sul1, aac[3]-IV, CITM, and dfrA1. The most prevalent serogroup among STEC was O26. Conclusions Our findings should raise awareness about antibiotic resistance in diarrheic calves in Iran. Clinicians should exercise caution when prescribing antibiotics.
    Full-text · Article · Jun 2014 · Biological research
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    • "Therefore, it is suggested that parasitic infestation may lead to ill-thrift either via subjecting calves to diarrhea, nutrition deprivation, and discomfort. Our explanation is supported by several studies, which showed that diarrhea is a main clinical finding of parasitic infestation in buffalo calves [18] [23]. In the examined calves, there was poor parasitic control, where 60% of ill-thrift calves did not receive treatment for parasites. "
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    ABSTRACT: Failure to grow (ill-thrift) in calves has a negative effect on animal production and health. The present study was carried out from November, 2009 to May, 2013 to investigate the risk factors of ill-thrift in buffalo calves. A total of 344 calves at 78 smallholder farms were selected randomly. A questionnaire was designed to include managemental, nutritional and disease risk factors. Serum selenium, copper, zinc, iron, calcium, phosphorus and magnesium were measured. Data were subjected to logistic regression analysis and results were expressed as p value, odds ratio (OR) and confidence interval (CI). Fifty-five calves (15.9%) showed ill-thrift. On animal level, the final multiple logistic regression model showed, a significant association between ill-thrift and early weaning (p<0.01; OR: 45.755; CI:4.35– 480.25), diarrhea (p<0.05; OR: 41.315; CI: 1.710 –998.0), indoor management (p<0.05; OR: 63.56; CI: 2.701–14.96) and low serum phosphorus (p<0.01; 292.0; CI:5.256 –16.23). On farm level, inadequate mineral supplementation (p<0.001; OR: 18.62; CI: 3.89–88.9). and irregular use of anthelmintics (p<0.05; OR: 7.95; CI: 1.53–41.23) were the potential factors. Clinically, ill-thrift calves were more likely to have alopecia (p<0.01), recumbency (p<0.01), emaciation (p<0.001), hypothermia (p<0.01), inappetance (p<0.001), lacrimation (p<0.001), hypomotile rumen (p<0.001), and pale mucous membrane (p<0.001). The results of the present study indicate that ill-thrift in buffalo calves could occur as a result of interaction between management errors and disease factors. Identification of the risk factors associated with ill-thrift may provide a useful information, which assist to construct the suitable preventive measures.
    Full-text · Article · Feb 2014 · Journal of Advanced Research
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