Distribution of Salmonella serovars and antimicrobial susceptibility of Salmonella Enteritidis from poultry in Zimbabwe

Avian Pathol. 2012;41(2):221-6. doi: 10.1080/03079457.2012.667558.

Abstract

A study was carried out to determine the distribution and antimicrobial susceptibility profiles of Salmonella serovars from chickens from large-scale commercial (LSC), small-scale commercial (SSC), and rural free-range (RFR) farms of Zimbabwe. Pooled cloacal swabs were collected for culture and isolation of Salmonella spp. A chi-square test was used to assess distribution differences of salmonellas among the farming sectors. Approximately 10% (283/2833) of the swabs were positive for Salmonella enterica, with only subspecies enterica (98.6%) and arizonae (1.4%) being detected. The prevalence of S. enterica varied significantly (P<0.05) among areas, with Harare (27.8%) and Buhera (1.3%) recording the highest and the least prevalence, respectively. S. enterica was only isolated from LSC and SSC farms, with the former having a significantly (P<0.001; χ(2)=155.3) higher prevalence than the latter. S. arizonae was only isolated from the SSC farms while none were obtained from the RFR farms. The serovars isolated were Salmonella Enteritidis (72.8%), Group C (20.1%), Group B (4.2%), Salmonella Typhimurium (1.1%) and Salmonella Gallinarum (0.4%). S. Enteritidis predominated in the urban/periurban areas. Approximately 26% (53/206) of S. Enteritidis isolates were resistant to one or more antimicrobial agents. Resistance to tetracycline was the most common, while no resistance was detected for furazolidone, neomycin and trimethoprim-sulfamethoxazole. There were 12.1% multi-drug-resistant S. Enteritidis isolates, and the resistance to ampicillin/kanamycin was predominant. The identification of multi-drug-resistant S. Enteritidis is of public health concern. Thus, stringent control of S. Enteritidis will reduce the public health risk of human salmonellosis.

MeSH terms

  • Animals
  • Anti-Infective Agents / pharmacology
  • Cross-Sectional Studies
  • Disk Diffusion Antimicrobial Tests / veterinary
  • Drug Resistance, Bacterial / genetics*
  • Poultry
  • Poultry Diseases / epidemiology*
  • Poultry Diseases / microbiology*
  • Prevalence
  • Salmonella / classification
  • Salmonella / genetics*
  • Salmonella Infections, Animal / epidemiology*
  • Salmonella enteritidis / drug effects
  • Salmonella enteritidis / genetics*
  • Species Specificity
  • Zimbabwe / epidemiology

Substances

  • Anti-Infective Agents