Antimicrobial effect of a drinking water additive comprising four organic acids on Campylobacter load in broilers and monitoring of bacterial susceptibility.

Application of organic acids via feed or drinking water is under discussion as a possible intervention strategy to reduce Campylobacter (C.) load in primary poultry production. A previous in vitro study showed that reduced concentrations of sorbic acid, benzoic acid, propionic acid, and acetic acid were required for antibacterial activity against Campylobacter when using a mixture of these 4 acids compared to when using the single acids. The present study aimed at determining the antibacterial efficiency of this combination in vivo as a drinking water additive for reducing shedding and intestinal C. jejuni colonization in broilers. Furthermore, we assessed whether the inoculated C. jejuni strain BfR-CA-14430 adapted in vivo to the applied organic acids. Results of this study showed that adding the organic acids consistently reduced Campylobacter loads in cloacal swabs. While significant reductions were observed within the entire study period, a maximum 2 log reduction occurred at an age of 18 d. However, after dissection at the end of the trial, no significant differences were detected in Campylobacter loads of cecal and colon contents compared to the control group. Susceptibility testing of re-isolates from cloacal swabs and cecal content revealed equal minimum inhibitory concentration (MIC) values compared to the inoculated test strain, suggesting that C. jejuni remained susceptible throughout the trial.

Effects of freezing temperatures and storage times on the quality and safety of raw turkey meat and sausage products.

In this study, the effect of frozen storage of turkey meat on the processing properties into raw sausages was investigated. For this purpose, meat from the Musculus pectoralis of male turkeys was frozen in 3 independent runs for 12 and 24 wk at -18°C and -80°C. After thawing, the meat was examined physicochemically and microbiologically and processed into raw sausages. The sausages were examined on d 0, 7, 14, 21, and 28 of storage. The parameters L*, a*, b*, pH-value and aw-value did not show any relevant significances between the experimental groups. The analysis of TBARS of the sausages made from frozen meat showed significantly higher values on d 14 and 28 compared to the unfrozen control group. Frozen storage also reduced the growth of Pseudomonas spp. and Enterobacteriaceae.

Effects of duration and temperature of frozen storage on the quality and food safety characteristics of pork after thawing and after storage under modified atmosphere.

The aim of this study was to investigate the influence of the duration of frozen storage (12 and 24 weeks) and the storage temperature (-18 °C or - 80 °C) on the shelf life of pork in MAP for up to 14 days after thawing. Frozen meat was compared to unfrozen meat in different physicochemical and microbiological parameters. The parameters a*, b*, pH value, cooking loss, shear force and antioxidant activity showed no significant changes depending on the freezing process. The total moisture loss was significantly higher for frozen/thawed pork compared to unfrozen pork. The storage loss of all frozen samples showed higher values than the unfrozen samples on all examination days. The level of TBARS reached comparable values for all experimental groups. On examination days 7 and 14, significantly lower values of total plate count (TPC) and Pseudomonas spp. were measured for frozen pork compared to unfrozen pork. The temperature of frozen storage had no significant influence on the quality of pork.

Use of meat juice and blood serum with a miniaturised protein microarray assay to develop a multi-parameter IgG screening test with high sample throughput potential for slaughtering pigs.

BACKGROUND: Serological screening of pig herds at the abattoir is considered a potential tool to improve meat inspection procedures and herd health management. Therefore, we previously reported the feasibility of a miniaturised protein microarray as a new serological IgG screening test for zoonotic agents and production diseases in pigs. The present study investigates whether the protein microarray-based assay is applicable for high sample throughput using either blood serum or meat juice. MATERIAL AND METHODS: Microarrays with 12 different antigens were produced by Abbott (formerly Alere Technologies GmbH) Jena, Germany in a previously offered 'ArrayTube' platform and in an 'ArrayStrip' platform for large-scale use. A test protocol for the use of meat juice on both microarray platforms was developed. Agreement between serum and meat juice was analysed with 88 paired samples from three German abattoirs. Serum was diluted 1:50 and meat juice 1:2. ELISA results for all tested antigens from a preceding study were used as reference test to perform Receiver Operating Characteristic analysis for both test specimens on both microarray platforms. RESULTS: High area under curve values (AUC > 0.7) were calculated for the analysis of T. gondii (0.87), Y. enterocolitica (0.97), Mycoplasma hyopneumoniae (0.84) and Actinobacillus pleuropneumoniae (0.71) with serum as the test specimen and for T. gondii (0.99), Y. enterocolitica (0.94), PRRSV (0.88), A. pleuropneumoniae (0.78) and Salmonella spp. (0.72) with meat juice as the test specimen on the ArrayStrip platform. Cohens kappa values of 0.92 for T. gondii and 0.82 for Y. enterocolitica were obtained for the comparison between serum and meat juice. When applying the new method in two further laboratories, kappa values between 0.63 and 0.94 were achieved between the laboratories for these two pathogens. CONCLUSION: Further development of a miniaturised pig-specific IgG protein microarray assay showed that meat juice can be used on microarray platforms. Two out of twelve tested antigens (T. gondii, Y. enterocolitica) showed high test accuracy on the ArrayTube and the ArrayStrip platform with both sample materials.