Salmonella Saintpaul (SSa) is increasingly reported from food and foodborne outbreak cases. Pulsed field gel electrophoresis (PFGE) is used for screening and tracking of Salmonella infections. Widespread use of antimicrobial agents in humans and food animals could result in antimicrobial resistant Salmonella serotypes. The aim of this study was to characterize S. Saintpaul (n = 28) isolated from various sampling locations at abattoir and meat processing plant lines in Ethiopia for phenotypic antimicrobial resistance and genotypic diversity, and to track its transfer routes. Sampling location, steps and occasions were considered for each isolate description. Antimicrobial sensitivity testing was performed against seven different antimicrobial agents using disc diffusion method. PFGE with XbaI® enzymatic genomic digestion with BioNumerics® analysis was used for genotypic diversity. Of all the isolates tested, only 17.9% were pan susceptible, and 82.1% were resistant to at least one and at most to three antimicrobials. All isolates were susceptible to gentamycin, trimethoprim-sulfamethoxazol and trimethoprim. Resistance to oxytetracycline (82.2%) was predominant followed by 3.6% resistance to each of chloramphenicol, neomycin and polymyxin B. PFGE analysis revealed three distinguishable clusters of pulsotypes but the majority of the isolates (25/28) belonged to cluster-I (SSaX1-4) pulsotype. Indistinguishable/similar cluster of (SSaX 1-4) isolates among and between sampling location, steps and occasions were observed. Majorities of S. Saintpaul (88%) in the cluster-I pulsotype were resistant to oxytetracycline. Our study indicated that oxytetracycline resistance is very common among the S. Saintpaul isolates studied; and the isolates were diverse with similar resistance profiles within the same genomic pulsotypes. Transfer of S. Saintpaul within, between and across sampling locations, during the same or different occasion were determined from SSaX 1-4 pulsotype while cluster-II (SSaX5) indicates transfer from abattoir to butchery. The unique isolate in cluster-III (SSaX6) shows the presence of other possible source of S. Saintpaul for the beef chain contamination.

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In Laborversuchen wurde die mikrobielle Toxizität der PCB‐Kongenere 5 (2.3–Dichlorbiphenyl), 8 (2, 4′‐Dichlorbiphenyl), 29 (2, 4, 5‐Trichlorbiphenyl) und des für Tiere extrem toxischen PCB 77 (3, 3′,4, 4′‐Tetrachlorbiphenyl) untersucht. Außerdem wurden die technischen Gemische Arochlor 1242 und 1260 geprüft. Als Versuchsobjekte dienten ein Podsol‐Ahe und ein Parabraunerde‐Ap Horizont. Die mikrobielle Toxizität wurde durch Messung der Langzeitatmung (CO2‐Abgabe), der Kurzzeitatmung (CO2‐Produktion bis 12 h nach Glucosezusatz) und der Dehydrogenaseaktivität (TTC‐Reduktion) erfaßt. Die Dichlorbiphenyle 5 und 8 hemmten die Lang‐ bzw. Kurzzeitatmung des Podsol‐Ahe bereits nach Zugabe von 1 mg/kg wahrend des gesamten Versuches (35 bzw. 28 Tage). Das Trichlorbiphenyl 29 wirkte dagegen erst bei Belastungen > 10 mg/kg aktivitätshemmend. PCB 77 beeinflußte mit Ausnahme einer kurzfristigen Anregung der Langzeitatmung die mikrobielle Aktivität des Podsol‐Ahe nicht. Aufgrund seiner höheren Sorptionskapazität wurden am Parabraunerde‐Ap mit allen PCB‐Kongeneren schwächere Effekte als am Podsol‐Ahe erzielt. Mit zunehmendem Chlorierungsgrad nahm die Toxizität der untersuchten PCBs ab. Die technischen Gemische hemmten die Langzeitatmung erst ab 50 mg/kg (Podsol‐Ahe) bzw. 100 mg/kg (Parabraunerde‐Ap), wobei sich Arochlor 1242 als effektiver erwies als Arochlor 1260.

Streptococcus suis (S. suis) is a zoonotic agent worldwide. Pigs are the main reservoir, mostly asymptomatic. Humans get the infection by contact and consumption of contaminated meat and meat products. In this study, samples from 38 pig carcasses fit for human consumption from 17 holdings were arbitrarily selected. From each carcass, seven tissue samples were taken and examined for the presence of S. suis, using conventional microbiology and PCR. In addition, virulence-associated factors (epf, arcA, sly, mrp) were tested with PCR. More isolates were PCR-positive for S. suis as compared to conventional testing, mostly in samples from the heart and from the mandibular lymphnodes. All isolates were epf negative, combinations of arcA, sly and mrp were found in some isolates. Six isolates were positive for arcA and mrp, five for arcA and sly. For three isolates the triple combination arcA + mrp + sly was found. These isolates originated from different pigs.