Abstract:
The present study was conducted from October 2020 to October, 2021 with the objectives of 
isolation and identification of Salmonella and E. coli from environmental sources in poultry 
farms in Harar and Haramaya towns, eastern Ethiopia. A total of 52 samples comprising 48 
from 12 poultry farms in Harar and 4 samples from 1 poultry farm in Haramaya were 
collected based on random sampling. Standard cultural and biochemical methods were used to 
isolate both Salmonella and E. coli. SPSS version 20.0 software (IBM) was used for the 
analyses of data. The overall prevalence of E. coli and Salmonella from the samples was 50% 
and 59.61%, respectively. The analysis of risk factors showed that Salmonella occurrence was 
significantly influenced (p<0.05) by manure disposal types, farm cleaning practices, and
educational status of farm workers. E. coli prevalence was significantly associated (p<0.05) 
with risk factors such as poultry farm systems, in that it was higher in traditional (85.5%) than 
modernized one (28.1%). The prevalences of E. coli and Salmonella spp based on sample 
types were 69.2% and 38.4% in water; 46.2% and 84.6% in litter; 46.2% and 69.23% in feed; 
and 38.5% and 46.2% in swab samples of poultry houses. Generally, the study revealed that 
contact surfaces in the poultry farms are the potential sources for the both E. coli and 
Salmonella and large proportions of farm environments are contaminated with the tested 
bacterial species. The isolated bacteria could have a significant public health consequence due 
to direct transmission from the environment as well as infected poultry and their products 
through the food chain. Thus, in the control of infectious diseases, it is important to give high 
priority in controlling dissemination of bacterial pathogens in the environments and poultry 
farms operational units should be based on modernized systems and in a way that is suitable 
for cleaning and disinfecting.