Characterization of Salmonella isolated from apparently healthy slaughtered cattle and retail beef in Hawassa, southern Ethiopia

Abstract

The present study was conducted to determine the occurrence, serotype distribution and antimicrobial resistance of Salmonella serotypes in slaughtered cattle, slaughterhouse environment and retail beef. Cecal content (CC), mesenteric lymph nodes (MLN), spleen and carcass swab (CS) samples (each, n=150) were collected from 150 cattle slaughtered at Hawassa municipality slaughterhouse. Floor swab specimens (SHFS) were collected on 11 occasions from the slaughterhouse, and 100 beef samples were collected from 100 butcher shops. The samples were cultured for Salmonella, following standard procedures. A total of 14 Salmonella isolates belonging to 3 serotypes namely Salmonella enterica serotype Muenchen (4 isolates), S. enterica serotype 1,4,5,12:i:- (5) and S. enterica serotype Korovi (5) were recovered. All of the 5 S. enterica serotype 1,4,5,12:i:- isolates belonged to phage type 120. Four (2.7%) of the slaughtered cattle carried Salmonella in their CC and/or MLN, while none of the spleen samples were positive for Salmonella. Salmonella was isolated from four (2.7%) CC and two (1.3%) MLN samples. Out of the total of 150 CS samples, two (1.3%) were found contaminated with Salmonella, while 4 (4%) of the 100 beef samples obtained from butcher shops yielded Salmonella. Two of the 11 (18%) SHFS were positive for Salmonella. All the four isolates from beef were S. enterica serotype Muenchen, while both of the isolates from MLN were S. enterica serotype1,4,5,12:i:-. Both S. enterica serotype1,4,5,12:i:- and S. enterica serotype Korovi were isolated from CC, CS and slaughterhouse environment. All the 14 isolates recovered during the study were tested and found pan-susceptible to a panel of 14 antimicrobials. The present study helped to update the information on the occurrence, serotype distribution and antibiogram of Salmonella in slaughter cattle and beef in Ethiopia.