Antibiotic sensitivity profile of Salmonella isolated from two slaughterhouses and human clinical cases

The antibiotic sensitivity of Salmonella strains isolated during the period 1996-98 from two industrial slaughterhouses of Northern Greece was detennined and compared with that of salmonellae isolated from human hospital cases during the period 1995-1997. For antibiotic sensitivity the disc agar diffusion method was used. Of 1874 samples obtained from the slaughterhouse environment (floors, worker\u27s hands and their knives), pork carcasses, by-products (livers and plucks) as well as lymph nodes and caecal contents 178 (9.5%) were positive for Salmonella spp. The salmonellae belonged to 22 serotypes. S. derby, S. london and S. typhimurium represented 25.8%, 15.2%, and 10.7% of the serotypes respectively. Of the salmonellae 59%, and 4.5%, were resistant and 33%, and 4.5% were intermediate sensitive to Tetracyclin, and Streptomycin, respectively and 26.4%, 14.6%, 5.1%, 1.7% and 1% were resistant to Ampicillin, Sulfamethoxa\u3eole I Trimethoprim, Chloramphenicol, Gentamicin, and Tobramycin respectively. Of the S. typhimurium strains 47% were resistant to Ampicillin and 41.2% to Chloramphenicol. Seven of the 19 strains were DT I 04, isolated for the first time in Greece, and multiple drug resistant. Of all isolates 5.1% were resistant to Chloramphenicol, the use of which is prohibited in food animal veterinary practice. Of the 422 salmonellae isolated at the Hospital of Infectious Diseases in Thessaloniki during the period 1996-98 77.4% were S. enteritidis and 17.7% S. typhimurium. Of the salmonellae isolated during 1995-1997, 76-79 % were resistant to Ampicillin and 1.2-1.5% to Chloramphenicol. Many of S. typhimurium strains isolated from the slaughterhouses and human cases exhibited the same antibiotic sensitivity profile a fact indicative of a potential transfer of animal strains to humans. Salmonellae of the same serotype exhibited different antibiotic resistance profiles, an indication of the presence of different clones within the same serotype. No S. enteritidis was isolated in slaughterhouses

Post harvest epidemioilogy of Salmonella enterica in pork: Prevalence in the environment, carcasses and by-products in two slaughterhouses in Greece (1996-1998)

In this study our objective was to estimate the prevalence of Salmonella enterica in the environment, on the pork carcasses and on several by-products in 2 industrial slaughterhouses over a 2-year period. In the period from 1/7/96 until 1/8/98, 1874 samples were obtained from the slaughterhouse environment (from the floor, the worker\u27s hands and their knives), product samples (from pork carcasses) and by products (livers and plucks). The prevalence of infection in pigs slaughtered at the sampling dates was estimated by testing samples from mesenteric lymph nodes and caecal content. Environmental samples were collected before the onset of slaughter. After the onset of slaughter and for every 50 pigs, a round of samplings of all sources mentioned above was repeated. Salmonella isolation and identification was carried out by standard cultural method. In total, based on the isolation method, 178/1874 (9.5%) samples were positive. The mean prevalence on floors, workers\u27 hands. workers\u27 knives, pork carcasses and by-products were 19.6% (range: 0%-100%), 5.2% (0%-50%), 3.1% (0%-37.5%), .3% (0%-88.9), 6.6% (0%-90%), respectively. The average prevalence of infection in pigs slaughtered at the sampling dates was 20.7% based on mesenteric lymph nodes and 15.2% based on caecal contents. Before the onset of slaughter, 37.5%, 6.3% and 8.7% of samples obtained from floors, worker hands and knives harbored Salmonella. This may reflect an inadequate plant hygiene. The frequent presence of Salmonella in the caecal contents and the lymph nodes may contribute to significant environmental contamination, including inspectors hands, eventually leading to final product contamination. The isolated salmonellae belonged to 22 serotypes. Among those, S. Derby and S. London were the most frequent representing 25.8% and 15.2% respectively. In conclusion, the frequent presence of Salmonella spp. in the lymph nodes, may indicate infection in the herd. Furthermore, the moderate prevalence of Salmonella on carcasses and by-products calls for further identification and institution of postharvest control options

A farm-level study of risk factors associated with the colonization of broiler flocks with Campylobacter spp. in Iceland, 2001 – 2004

<p>Abstract</p> <p>Background</p> <p>Following increased rates of human campylobacteriosis in the late 1990's, and their apparent association with increased consumption of fresh chicken meat, a longitudinal study was conducted in Iceland to identify the means to decrease the frequency of broiler flock colonization with <it>Campylobacter</it>. Our objective in this study was to identify risk factors for flock colonization acting at the broiler farm level.</p> <p>Methods</p> <p>Between May 2001 and September 2004, pooled caecal samples were obtained from 1,425 flocks at slaughter and cultured for <it>Campylobacter</it>. Due to the strong seasonal variation in flock prevalence, analyses were restricted to a subset of 792 flocks raised during the four summer seasons. Flock results were collapsed to the farm level, such that the number of positive flocks and the total number of flocks raised were summed for each farm. Logistic regression models were fitted to the data using automated and manual selection methods. Variables of interest included manure management, water source and treatment, other poultry/livestock on farm, and farm size and management.</p> <p>Results</p> <p>The 792 flocks raised during the summer seasons originated from 83 houses on 33 farms, and of these, 217 (27.4%) tested positive. The median number of flocks per farm was 14, and the median number of positive flocks per farm was three. Three farms did not have any positive flocks. In general, factors associated with an increased risk of <it>Campylobacter </it>were increasing median flock size on the farm (p ≤ 0.001), spreading manure on the farm (p = 0.004 to 0.035), and increasing the number of broiler houses on the farm (p = 0.008 to 0.038). Protective factors included the use of official (municipal) (p = 0.004 to 0.051) or official treated (p = 0.006 to 0.032) water compared to the use of non-official untreated water, storing manure on the farm (p = 0.025 to 0.029), and the presence of other domestic livestock on the farm (p = 0.004 to 0.028).</p> <p>Conclusion</p> <p>Limiting the average flock size, and limiting the number of houses built on new farms, are interventions that require investigation. Water may play a role in the transmission of <it>Campylobacter</it>, therefore the use of official water, and potentially, treating non-official water may reduce the risk of colonization. Manure management practices deserve further attention.</p

Antibiotic sensitivity profile of Salmonella isolated from two slaughterhouses and human clinical cases

The antibiotic sensitivity of Salmonella strains isolated during the period 1996-98 from two industrial slaughterhouses of Northern Greece was detennined and compared with that of salmonellae isolated from human hospital cases during the period 1995-1997. For antibiotic sensitivity the disc agar diffusion method was used. Of 1874 samples obtained from the slaughterhouse environment (floors, worker's hands and their knives), pork carcasses, by-products (livers and plucks) as well as lymph nodes and caecal contents 178 (9.5%) were positive for Salmonella spp. The salmonellae belonged to 22 serotypes. S. derby, S. london and S. typhimurium represented 25.8%, 15.2%, and 10.7% of the serotypes respectively. Of the salmonellae 59%, and 4.5%, were resistant and 33%, and 4.5% were intermediate sensitive to Tetracyclin, and Streptomycin, respectively and 26.4%, 14.6%, 5.1%, 1.7% and 1% were resistant to Ampicillin, Sulfamethoxa>ole I Trimethoprim, Chloramphenicol, Gentamicin, and Tobramycin respectively. Of the S. typhimurium strains 47% were resistant to Ampicillin and 41.2% to Chloramphenicol. Seven of the 19 strains were DT I 04, isolated for the first time in Greece, and multiple drug resistant. Of all isolates 5.1% were resistant to Chloramphenicol, the use of which is prohibited in food animal veterinary practice. Of the 422 salmonellae isolated at the Hospital of Infectious Diseases in Thessaloniki during the period 1996-98 77.4% were S. enteritidis and 17.7% S. typhimurium. Of the salmonellae isolated during 1995-1997, 76-79 % were resistant to Ampicillin and 1.2-1.5% to Chloramphenicol. Many of S. typhimurium strains isolated from the slaughterhouses and human cases exhibited the same antibiotic sensitivity profile a fact indicative of a potential transfer of animal strains to humans. Salmonellae of the same serotype exhibited different antibiotic resistance profiles, an indication of the presence of different clones within the same serotype. No S. enteritidis was isolated in slaughterhouses.</p