To assess the antimicrobial effect of a commercial steam-vacuuming system newly implemented after slaughtering, 105 cattle carcasses were examined for total viable counts (TVC) at four different areas. Before steam vacuuming, mean TVC of the excision samples were comparable at the perineal area and brisket (3.0-3.1 log CFU cm-2) or the hind leg and shoulder (2.6-2.7 log CFU cm-2). Steam vacuuming reduced mean TVC by 0.9, 0.7, 0.6, and 0.4 log CFU cm-2 at the perineal area, hind leg, shoulder, and brisket, respectively. With regard to the distribution of counts, steam vacuuming increased the proportion of TVC results <3.0 log CFU cm-2 from 74.8% (62.9-87.6% at carcass areas) to 86.7% (71.4-97.1% at carcass areas). Thus, steam vacuuming after slaughtering might be useful for the reduction of contamination in designated carcass areas, but the effect must not be overestimated and decontamination treatments always must be seen part of an integral food safety system.

Many parts of pork meat processing are currently not used for human consumption in Switzerland, although they are of great nutritional value. Therefore, data on the occurrence of pathogenic organisms on byproducts is extremely scarce and the prevalence and population structure of Staphylococcus aureus on meat processing sidestreams is unknown. Hence, abattoir byproducts of pork origin including ear, forefoot, heart, intestine, liver, rib bone, sternum, bladder, stomach, hind foot and tongue originating from six abattoirs were screened for S . aureus . The obtained isolates were investigated by spa typing and DNA microarray analysis to reveal their genomic profile and population structure. The prevalence of S . aureus was generally low with a mean of 8%. In total, 40 S . aureus strains were detected and assigned to 12 spa types (t015, t1491, t1778, t091, t337, t899, t2922, t7439, t1333, t208, t4049, t034) and seven clonal complexes (CC1, CC7, CC9, CC30, CC45, CC49, CC398). Detected enterotoxin genes included sea , seb , sec , seh , sel and egc encoded toxin genes seg , sei , sem , sen , seo , and seu . None of the isolates harbored genes conferring methicillin resistance, but blaZ/I/R genes causing penicillin resistance were frequently found. In addition, strains from CC398 exhibited tetM and tetK , conferring tetracycline resistance. Similarity calculations based on microarray profiles revealed no association of clonal complexes with particular body parts, but revealed a certain correspondence of clonal complex and originating abattoir.

Clostridium estertheticum and C. estertheticum -like spp. are obligate anaerobic psychrophiles causing “blown pack” spoilage of chilled vacuum-packed meat. The present study aimed at detecting and isolating these spoilage bacteria in fecal samples of cattle of different ages at the slaughterhouse level. One-hundred-and-two swab fecal samples were obtained and enriched anaerobically in pre-reduced peptone-yeast-glucose-starch medium (PYGS) for three weeks at 4°C then screened for C. estertheticum and C. estertheticum -like spp. using a 16S rRNA gene-based real-time PCR assay (RT-PCR). The RT-PCR positive samples were further enriched for 3 weeks in PYGS then subjected to an ethanol (50% v/v) and lysozyme (4 mg/ml) treatment. Isolation was carried out anaerobically on Columbia Agar with 5% defibrinated sheep blood at 4°C for three weeks. Isolated strains were identified morphologically and by their 16S rRNA gene. Thirty-nine percent (n=40/102) of the samples were RT-PCR positive. The frequency of positive samples was 45% (n=9/20), 43% (n=23/54) and 29% (n=8/28) in calves, young cattle and cows/bulls aged ≤ 160, 161-1000 and &gt;1000 days, respectively. Six strains were isolated from six out of the 40 RT-PCR positive samples. Out of these, five were from the calves (n=1) and young cattle (n=4). The six isolates were identified as C. estertheticum (n=1), C. frigoriphilum (n=1) and C. estertheticum -like spp. (n=4). The present findings confirm that feces of cattle are an important source of psychrophilic Clostridium spp. The fecal carriage among livestock animals at slaughter is strongly correlated with the risk of carcass contamination. Therefore, the maintenance of slaughter hygiene is of central importance.

veterinarians from ten large-animal clinics located in various regions of Switzerland (Cantons of Aargau, Berne, Grisons, St.Gallen, Ticino and Zurich) collected 81 quarter milk samples from 49 beef cows with mastitis. The milk samples were submitted to the Institute for Food Safety and Hygiene, where culture and antibiotic susceptibility testing was done. The following data were recorded: Breed, results of the California Mastitis Test (CMT) and macroscopic assessment of the secretion (normal, watery, presence of clots and/or blood, foul odour), the stage of disease (acute, chronic, subclinical), the antibiotic used in pretreatment, the clinical appearance of the affected quarter, signs of systemic illness, lactation