Prevalence and antimicrobial resistance of Salmonella isolated from bovine and ovine samples in slaughterhouses of Algiers, Algeria

Abstract

The aims of our work are to estimate the prevalence of Salmonella isolated from carcasses and feces of cattle and sheep in the two biggest slaughterhouses in Algiers, Algeria, and to characterize the obtained strains by serotyping and antimicrobial resistance testing. The detection of Salmonella was performed by the conventional culture method and isolates were confirmed by PCR. Susceptibility to antibiotics was carried out by agar disc diffusion method. The results showed that 10.17% of samples were Salmonella positive. Carcass samples were more contaminated than fecal samples. Serotyping of the 84 Salmonella isolates has enabled to identify 10 different serovars; the most predominant was S. Muenster. The invA gene was detected in 96.43% of isolates whereas all S. Typhimurium strains were positive for spy gene. Sixty-eight (80.95%) isolates were resistant to at least one of the 28 antibiotics tested and exhibited 17 different antimicrobial resistance patterns. The most frequently observed resistance was to streptomycin (69.05%). While 22.62 % of the isolates were MDR, two S. Typhimurium showed an‘‘ACSSuT’’ pentaresistance pattern. Considering the importance of this group of bacteria for public health, Salmonella control is necessary at several steps of food production to ensure safe products for consumers.

Serotype diversity and slaughterhouse-level risk factors related to Salmonella contamination on poultry carcasses in Algiers

“…Except for S. Typhimurium, the same serotypes were recently isolated in northeastern Algeria in broiler breedings and slaughterhouses with predominance of S. Kentucky [46]. In east part of Algeria, S. Kentucky was isolated from feces on laying-hen flocks [22] and found to be the most prevalent in dairy cattle breedings (unpublished data) while Nouichi et al [47] registered a 13.8% Salmonella-contaminated ovine and bovine carcasses at Algiers' slaughterhouses. Accordantly, Kentucky was the most isolated serotype in Nigerian commercial chicken layer farms [48] and broiler chicken carcasses in the USA [32].…”

“…According to Foley et al [53], the emergence of S. Kentucky and S. Heidelberg in poultry coincides with the decrease of S. Enteritidis targeted by a number of control programs over the past decades. S. Virginia more frequently identified in chicken samples than in turkey ones, was lately reported for the first time in Algeria as a serotype associated only with neck skin broiler [46] and ovine carcass samples [47]. Little is known about this serotype except a MDR profile including resistance to tetracycline [54] and isolation only from poultry in Egypt [55].…”

Assessment of Microbiological Load of Small Ruminant Carcasses, Livers, Some Lymph Nodes, Tools and Knife Samples in Slaughterhouse

“…On the other hand, some researchers found that Salmonella spp. prevalence in small animal carcasses was between 0.62% and 14.1% (23)(24)(25)(26)(27). It is difficult to make comparison among the studies in point of the Salmonella prevalence.…”

The whole issue

“…cause three million deaths annually worldwide (Mohammadzadeh et al, 2018), non-typhoidal Salmonella spp. are believed to cause 93.8 million infected cases of acute gastroenteritis and 155,000 deaths yearly (Eng et al, 2015;Nouichi et al, 2018). Salmonellosis comprises a big common health load and represents considerable costs in many countries.…”