Prevalence and antimicrobial resistance of salmonellae isolated from eggs of local chicken in selected towns of Ethiopia.

Background: Salmonellosis is one of the most common food-borne diseases in industrialised and developing countries. In recent year, an increase in antimicrobial resistance among different Salmonella serotypes has been observed.

Objective: A cross-sectional study was conducted to assess the prevalence and antimicrobial susceptibility of Salmonella isolated from local chicken eggs in four selected towns in Ethiopia.

Methods: A total of 115 eggs were examined to detect Salmonella by using standard microbiological methods. The susceptibilities of the isolates to nine antimicrobials were tested by the Kirby-Bauer disk diffusion method.

Result: The study revealed that of the 115 eggs examined, 22 (19.1%) were positive for Salmonella of which 14 (12.2%) and 8 (7%) of the isolates were from shells and contents, respectively. The occurrence of Salmonella in egg shells and content and between different altitudes did not differ significantly (p > 0.05). Most isolates were resistant to more than three antimicrobials with a high resistance to kanamycin, ampicillin, nalidixic acid, cotrimoxazole, oxytetracycline and chloramphenicol.

Conclusion: The results indicate the potential importance of local chicken eggs as source of multiple antimicrobial-resistant salmonellae and the need for proper cooking before consumption. Further studies are required to describe the epidemiology of Salmonella in various agroclimatic zones of Ethiopia.