Prevalence, genetic diversity and antimicrobial susceptibility of Listeria monocytogenes isolated from open-air food markets in Greece

A total of 210 food samples originating from milk products, ready-to-eat salads, raw meat and raw meat products purchased in ten open-air market places in Thessaloniki, Greece, were analyzed for the presence of Listeria monocytogenes. Thirty (14.3%) contained L. monocytogenes with the highest prevalence in raw meat (27.5%), raw meat products (18%) and cheese (8%). The strains were susceptible to 16 antimicrobials as determined by microbroth dilution, except one strain which displayed resistance to tetracycline (MIC > 32 mu g/ml). This strain carried the tetracycline resistance gene tet(M). Pulsed-field gel electrophoresis (PFGE) revealed a low genetic diversity among the isolates, irrespective of their origin. This suggests that dominant L monocytogenes clones are widespread in different food product types in open-air food markets in Greece. The high prevalence of L monocytogenes in these products indicates that appropriate hygienic measures and periodic bacteriological controls are also necessary in open-air food markets to reduce contamination with food-borne pathogens. Greek specialties made with raw meat and raw milk may contain L monocytogenes and should not be consumed by persons at risk. (C) 2008 Elsevier Ltd. All rights reserved

Meloxicam as adjunctive therapy in treatment and control of porcine respiratory disease complex in growing pigs

Objective: To determine the efficacy of injectable meloxicam as adjunctive therapy to antimicrobial medication in treatment and control of porcine respiratory disease complex (PRDC) in growing pigs. Methods: A total of 162 ninety-day-old pigs showing early clinical signs of PRDC were weighed (Day 0) and allocated into two treatment groups, Controls (n = 82) and Meloxicam (n = 80), in a randomized block design (approximately 20 pigs per pen, four pens per treatment per replicate). In-feed chlortetracycline (800 g per tonne; 20 mg per kg body weight per day) was administered to both groups for 8 consecutive days (Days 0 to 7). On Day 0, Controls received a single injection of a placebo and the Meloxicam group received a single injection of meloxicam (0.4 mg per kg body weight). Respiratory signs were assessed per individual animal and per treatment group Days 0 to 7. Frequency of additional injectable medications, mortality rate, and growth rate were assessed until the end of the growing phase (117 days of age; Day 27). The lungs of all dead animals were submitted for bacteriological culture and pathological examination. Results: Clinical scores, frequency of treatment with additional injectable medications, and mortality rate were lower and growth performance was better in meloxicam-treated animals than in Controls. Implications: Meloxicam as an adjunct to oral antibiotic therapy may contribute to treatment and control of PRDC by accelerating recovery from respiratory inflammation, enhancing restoration of normal growth rate, and reducing mortality rate