Prevalence, risk factors and antimicrobial susceptibility profile of Salmonella isolated from dogs of Ambo, Bako and Gojo towns of West Shoa, Ethiopia

Abstract

Salmonella is the most known zoonotic bacterial agent, which produces sal-monellosis in animals as wells as in humans. The objectives of this study were to estimate the prevalence, to determine antimicrobial susceptibility and to assess risk factors associated with Salmonella shedding in dogs in selected towns of West Shoa Zone, Oromia, Ethiopia. Using a cross-sectional design, a total of 438 rectal swab samples were collected from randomly selected dogs for isolation and identification of Salmonella using standard procedures. A questionnaire survey was also administered. The results showed that 48 (11.0%, 95%, [CI]: 8.2%-14.3 %) dogs were positive for Salmonella.The occurrenceof Salmonella was 10.9% (26/238), 11.6% (15/129) and 9.9% (7/71) in Ambo, Bako and Gojo towns respectively. Salmonella shedding was significantly higher in older dogs (15.0%) than younger ones (6.1 %) (P<0.05). The occurrence of Salmonella was not significantly associated with study towns, sex, breed of dogs,educational level of owners, presence of other domestic animals and housing system(P>0.05). Multivariable logistic regression analysis showed that the odds of isolation of Salmonella was significantly higher in old than young dogs (OR): 2.6, 95% CI: 1.3-5.6, P=0.007) and in dogs eating mixed type of feeds (raw animal products, household leftover) than cooked feed (OR = 9.0, 95% CI: 1.2-68.1, P=0.033). There was also a significant difference between kebeles of the study areas in that Salmonella isolation was nearly nine times higher in Bako Kebele 02 (P=0.005) as compared to Ambo kebele 03. Salmonella isolates have developed the highest level of resistance for ampicillin (100%), tetracycline 60 Zewdu et al., Ethiop. Vet. (93.3%) and streptomycin (80.0 %), however, all isolates were susceptible to Norfloxacin. The occurrence of Salmonella, most of which resistant to commonly used antimicrobials, in rectal swab samples show the potential threat dogs may pose to public health in the study area.