Among 800 stool specimens from patients with diarrhea submitted by Primary Care Centers for routine analysis to the Hospital of León (NW Spain) Microbiology and Parasitology Service, 32 (4%) were tested positive for Aeromonas spp. Mixed infections with other enteric pathogens occurred in 12 patients. A. caviae was isolated from 23 clinical specimens. There were also patients infected with A. media, A. hydrophila, A. bestiarum, and A. veronii biovar veronii. All but three isolates carried one or more of the virulence genes. The incidence of the alt, hlyA, aerA, ast, and laf genes was 71.9, 28.1, 25.0, 18.8, and 9.4%, respectively. The alt(+)/ast(+) combination was detected in four isolates and the aerA(+)/hlyA(+) combination was detected in the two A. hydrophila isolates. None of the strains harbored the TTSS, stx1, or stx2 genes and nine bore plasmids. Thirty clinical isolates and a collection of 12 A. caviae and A. media strains obtained from León municipal drinking water over the study period were typed by pulsed-field gel electrophoresis (PFGE). PFGE patterns revealed genetic relatedness and persistence over time among water isolates and some clinical isolates. Interestingly, one A. caviae (aerA(-)/hlyA(-)/alt(+)/ast(-)/laf(+)) human isolate and two A. caviae (aerA(-)/hlyA(-)/alt(+)/ast(-)/laf(+)) drinking water isolates had indistinguishable PFGE patterns, suggesting waterborne infection.

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Thirty-two Merino lambs fed barley straw and a concentrate alone (CONTROL) or enriched with vitamin E (VITE006) or carnosic acid (CARN006; CARN012) were used to assess the effect of these antioxidant compounds on meat quality attributes. The animals were slaughtered after being fed for at least 5weeks with the experimental diets. The longissimus lumborum samples of VITE006, CARN006 and CARN012 groups showed higher values (P<0.001) of L* (lightness) through the complete storage period under modified atmosphere when compared to the CONTROL group. Moreover, the VITE006 and CARN012 samples revealed lower discoloration when compared to the CONTROL group, these differences being more apparent in a less color stable muscle such as gluteus medius (P<0.05 for hue after 14days of refrigerated storage). Meat sensory traits were not significantly affected by carnosic acid and microbiological analyses were not conclusive at the doses administered.

Even though worldwide production of rabbit meat is >1,000,000 tons, little information is available for rabbit meat microbiology. This study provides data on the prevalence of Salmonella, Escherichia coli O157:H7, Yersinia enterocolitica, Listeria spp., motile Aeromonas spp., and Staphylococcus aureus on rabbit meat. A total of 24 rabbit carcasses from two abattoirs and 27 rabbit meat packages from supermarket displays were examined. In addition to culturing methods, associated virulence genes were investigated by PCR in suspect isolates and samples. Neither Salmonella nor E. coli O157:H7 was detected. All samples were negative for virulence-associated invA, stx1, and stx2 genes. At one abattoir, two carcasses (3.9%) carried Y. enterocolitica yst-, and two were positive for the yst gene, although viable Y. enterocolitica cells were not recovered from these samples. Seven samples (13.7%) were contaminated with Listeria. Of them, three were positive for hly and iap genes (Listeria monocytogenes hly+ / iap+), two carried Listeria seeligeri, one carried Listeria ivanovii, and one carried Listeria innocua. For detectable motile Aeromonas spp. (average count, 1.77 +/- 0.62 log CFU/g), the contamination rate was 35.3%, although ca. 90% of the samples were positive for the aerA and/or hlyA genes. The majority of aeromonad isolates were Aeromonas hydrophila aerA+ / hlyA+. Aeromonas caviae, Aeromonas popoffii, Aeromonas schubertii, and the two biovars of Aeromonas veronii were also isolated. The prevalence of S. aureus contamination (average count, 1.37 +/- 0.79 log CFU/g) was 52.9%. Among 27 S. aureus isolates, two harbored genes for staphylococcal enterotoxin B (seb), and two harbored genes for staphylococcal enterotoxin C (sec). The remaining isolates were negative for sea, seb, sec, sed, and see.

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