Quantification and prevalence of Salmonella in beef cattle presenting at slaughter

Abstract

Methods and Results: Automated immunomagnetic separation (AIMS) was used for detection and isolation of Salmonella enriched from cattle faeces. Salmonella were enumerated from positive samples using a combination of the Most Probable Number (MPN) technique and AIMS. A total of 310 faecal samples were tested, 155 were from lot-fed cattle and 155 from grass-fed cattle. Salmonella spp. were isolated from 21 (6AE8%) of the cattle and the prevalence amongst grass-fed cattle (4AE5%) was not significantly different to that found in lot-fed cattle (9%). Counts of Salmonella in positive faeces varied from <3 MPN g)1 of faeces to 2AE8 · 10 3 MPN g )1 and 71% of positive samples had counts <10 MPN g )1 faeces. There was no significant difference in the mean log 10 number of Salmonella in faeces of cattle from each production system. Conclusion: Low numbers of beef cattle were found to shed Salmonella at the time of slaughter and the prevalence and the associated faecal concentrations did not vary significantly with the pre-slaughter production system (grass or lot feeding). The faecal concentration of Salmonella in the majority of faeces was low (<10 MPN g )1 ) with few high concentrations up to 3 · 10 3 MPN g )1 , suggesting there may be a low risk of carcase contamination.Significance and Impact of the Study: Beef cattle do not appear to be a major source of entry of Salmonella into the human food chain and the quantitative information contained in this study can be used in quantitative assessments of the associated risk of human salmonellosis.

Prevalence and antimicrobial resistance profiles of Salmonella enterica serovars isolated from slaughtered cattle in Bahir Dar, Ethiopia

“…Salmonella Typhimurium and Salmonella Newport were the most frequently isolated serovars, each accounting for 21.4% of the total isolates. The frequency of isolation of Salmonella Typhimurium was consistent with the report of Alemayehu et al (2003) and Fegan et al (2004) who found Salmonella Typhimurium as being the dominant serovar among their isolates. Salmonella Infantis and Salmonella Mishmarhaemek were detected with prevalences of 17.9% and 7.1%, respectively.…”

“…The prevalence of Salmonella from carcasses was in agreement with the work of Alemayehu et al (2003) who reported prevalence of 3.1% and 2.8% from muscles of the diaphragm and the abdomen, respectively. Fegan et al (2004) also reported carcass contamination of 2% from an abattoir in Australia. In any case, carcass contamination levels have to be taken with caution; as the presence of even a single carrier animal can be a potential source of contamination of the carcasses, environment or personnel.…”

Prevalence of Salmonella Strains in Cattle Breeding in the District of Abidjan (Côte d'Ivoire)

“…In this study the prevalence (20%) is much higher than that reported by Fegan et al, (2004) in Australia, which was 6.88%. In the United States, the prevalence of Salmonella in cattle faeces in farms was reported to be less than 7% (Losinger et al, 1997;Fedorka-Cray et al, 1998;Dargatzet et al, 2003).…”

Antimicrobial Drug Resistance and Molecular Characterization of Salmonella Isolated from Domestic Animals, Humans and Meat Products

“…Other researchers (Dargatz et al, 2000) have reported a lower prevalence (1.4 to 4.5%) than that observed by Theis et al (2005Theis et al ( , 2007 while others (Fegan et al, 2004) have reported Salmonella prevalence as high as 16%. It is possible that the lower prevalence reported by Theis et al (2005Theis et al ( , 2007 could have been attributed to the smaller sample (N =212) of cattle compared to that of other researchers.…”