High Salmonella load with serovar virchow dominance pose major public safety risk in postchill broiler carcasses

The objective of this study was to determine Salmonella contamination levels, presence and serovar distribution in broiler carcasses before and after chilling, as well as to evaluate the effectiveness of chilling process. A total of 96 pooled neck skin samples (PNSS) of 48 prechill (PreC) and 48 postchill (PosC) carcasses, representing 480 broilers collected in 6 mo' period were analyzed using ISO 6579-2:2012 Miniaturized Most Probable Number (ISO-mMPN) technique. Species confirmation and serovar identification was performed by Salmonella-specific real-time PCR (Salm-PCR) and conventional serotyping, respectively. Mean Salmonella count was 1.84 log10 MPN/g in PreC, and 1.48 log10 MPN/g in PosC samples, indicating a statistically significant reduction of 0.36 log10 MPN/g (p < 0.05) in the counts by plant's air chill system. Salmonella positivity reduced from 97.9% (47/48) in PreC to 85.42% (41/48) in PosC samples, confirmed by Salm-PCR with identified serovars as S. Virchow (89.77 %) followed by S. Schwarzengrund (9.09%) and S. Bredeney (1.14%). Persistence of high load and prevalence of Salmonella with serovar Virchow dominance (other than the ones mandated in current guidelines) in the final product contributes significant and up to date data to relevant literature, and provides unbiased epidemiological reference to legal authorities for future relevant revisions.

Effect of Dietary Oregano and Rosemary Essential Oil Supplementation on Growth Performance and Cecal Microbiota of Broilers

In this study, the effect of dietary supplementation of oregano and rosemary essential oils (EO) on growth performance and cecal microbiota of broilers were investigated. A total of 450 1-d-old male Ross-308 broilers were divided into 5-experimental groups (10 replicates of 9 chickens): a Control (C), fed a basal diet; four treatments, which received a basal diet supplemented with oregano and rosemary EOs individually (O, 300 mg/kg oregano EO; R, 300 mg/kg rosemary EO) and combined (OR1, 150 mg/kg oregano EO + 150 mg/kg rosemary EO; OR2, 200 mg/kg oregano EO + 200 mg/kg rosemary EO). Body weight (BW), feed intake (FI), body weight gain (BWG), feed conversion ratio (FCR), and cecal microbiota (coliforms, clostridia and lactobacilli) were determined weekly, and at 42 d, respectively. BW in R (p<0.05) and OR2 (p<0.001), and BWG and FCR in OR2 (p<0.05) were significantly higher than C at 42 d, despite no difference in FI in any group during experimental period. Counts of cecal coliforms (p<0.001) and clostridia (p<0.01) decreased, and lactobacilli (p<0.001) increased substantially between C and treatment groups. Results indicated that combined oregano and rosemary EO (200 mg/kg ea) supplementation significantly increased BW and BWG, improved FCR in 1-42 d, lowered coliform and clostridial, and increased lactobacilli counts suggesting a beneficial shift in cecal microbiota.

Salmonella detection in poultry meat and meat products by the Vitek immunodiagnostic assay system easy Salmonella method, a LightCycler polymerase chain reaction system, and the International Organization for Standardization method 6579

This study was conducted to evaluate the capability of the Vitek immunodiagnostic assay system easy Salmonella (VIDAS ESLM) method and a specific real-time PCR system (LightCycler, LCPCR) to complement the International Organization for Standardization Method 6579 (ISO) in detecting Salmonella from a total of 105 naturally contaminated samples comprised of poultry meat and poultry meat products. The detection limit of ISO and LCPCR was 9 cfu/mL for both poultry meat and poultry meat products, whereas that of VIDAS ESLM with both sample types was determined to be 90 cfu/mL. Twelve (33.33%), 11 (30.55%), and 18 (50.00%) out of 36 poultry meat samples were positive for Salmonella by ISO, VIDAS ESLM, and LCPCR, respectively. Salmonella detection rates from poultry meat products were 5.80% for ISO and 8.69% for LCPCR, whereas none of these products tested positive by VIDAS ESLM. In poultry meat samples, VIDAS ESLM and LCPCR detection results were in substantial agreement with ISO, with the relative accuracy, sensitivity, and specificity rates of 97.2, 91.7, and 100%, respectively, for VIDAS ESLM and 83.3, 100, and 75%, respectively, for LCPCR. This is the first report on the evaluation of both VIDAS ESLM and LCPCR to complement ISO for the rapid detection of Salmonella in poultry meat and meat products. We determined that both VIDAS ESLM and LCPCR have the potential to complement the ISO standard culture method in the rapid screening of Salmonella from naturally contaminated poultry meats. For the poultry meat products, VIDAS ESLM and LCPCR can be used for rapid primary screening, and they should be complemented absolutely by ISO. Although LCPCR can preferentially be used for initial screening poultry meat products, the results should definitely be confirmed by ISO. Also, the VIDAS ESLM did not seem to be a suitable method for detecting Salmonella in poultry meat products.