The extraction of DNA is a critical step for species identification by PCR analysis in processed food and feed products. In this study, eight DNA extraction procedures were compared—DNeasy Blood and Tissue Kit, DNeasy mericon Food Kit, chemagic DNA Tissue 10 Kit, Food DNA Isolation Kit, UltraPrep Genomic DNA Food Mini Prep Kit, High Pure PCR Template Preparation Kit, phenol—chloroform extraction, and NucleoSpin Food—Using self-prepared samples from both raw and heat-processed and/or mechanically treated muscles and different types of meat products and pet food (pork, beef, and chicken). The yield, purity, and suitability of DNA for PCR amplification was evaluated. Additionally, comparisons between the effectiveness of various extraction methods were made with regard to price, and labor- and time-intensiveness. It was found that the DNeasy mericon Food Kit was the optimal choice for the extraction of DNA from raw muscle, heat-treated muscle, and homemade meat products from multiple and single species.

Helicobacter suis is the second most prevalent Helicobacter species in the stomach of humans suffering from gastric disease. This bacterium mainly inhabits the stomach of domesticated pigs, in which it causes gastric disease, but it appears to be absent in wild boars. Interestingly, it also colonizes the stomach of asymptomatic rhesus and cynomolgus monkeys. The origin of modern human-, pig- or non-human primate-associated H. suis strains in these respective host populations was hitherto unknown. Here we show that H. suis in pigs possibly originates from non-human primates. Our data suggest that a host jump from macaques to pigs happened between 100 000 and 15 000 years ago and that pig domestication has had a significant impact on the spread of H. suis in the pig population, from where this pathogen occasionally infects humans. Thus, in contrast to our expectations, H. suis appears to have evolved in its main host in a completely different way than its close relative Helicobacter pylori in humans.

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The halal meat industry is today a reality in many regions of the world, including the European Union. The main religious laws in the area of halal meat production were legislated in ancient times and may be unchangeable due to their sanctity perceived by faithful Muslims, while the modern technology used in the meat industry is constantly evolving and being updated. The objective of this study is to highlight the points of controversy between the principles of halal and the technological means currently used in the meat industry. Modern slaughter practices, including animal fasting prior to slaughter, animal body position, the location of the incision during slaughter, stunning and mechanical slaughter, are reviewed. The purpose of preslaughter feed availability according to halal criteria could be to ensure greater welfare for animals, though feed withdrawal is necessary today. Although there is no clear unified opinion among the Islamic sects, reversible stunning of animals is generally accepted. A neck cut at a higher position than the conventional low cut in cattle may reduce the compromise in welfare (the onset of unconsciousness), minimise false aneurysm and be compatible with halal criteria. This study may contribute towards consideration being given to technology that is not in conflict with the religious legislation, while at the same time meeting the requirements of the modern meat industry.

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The most common techniques used to identify tuna species include methods based on the detection of specific DNA. The quality of species-specific DNA crucially affects the efficiency of amplification during the subsequent polymerase chain reaction (PCR). Detection of DNA in processed products can be adversely affected by DNA fragmentation during the processing steps and the use of ingredients that may inhibit the PCR reaction. In this study, several processing treatments applied to the muscle tissue of yellowfin tuna (Thunnus albacares) were evaluated. For DNA isolation three DNA extraction methods were compared. The concentration, purity, and amplificability of DNA were tested. The results revealed the variability among extraction procedures in terms of DNA quality and quantity in tuna muscle tissue processed under different processing technologies. ARTICLE HISTORY

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Microbial contamination of poultry carcasses can be influenced by many factors during transport and slaughtering. The aim of this study was to evaluate the impact of four processing steps (plucking, evisceration, washing and chilling) on the total viable counts (TVC), counts of Escherichia coli, Salmonella spp. and Listeria spp. incidence on broiler carcasses. A total of 160 broiler carcasses originating from one farm were collected during one year period at a Czech slaughterhouse and examined. Both TVC and E. coli counts decreased during processing from 4.6 log cfu/cm 2 and 3.5 log cfu/cm 2 to 3.7 log cfu/cm 2 and 1.8 log cfu/cm 2 , respectively, with a major impact of washing on TVC and washing and chilling on E. coli decrease (P < 0.001). Both Salmonella spp. (6 strains) and Listeria spp. (12 strains, none of L. monocytogenes) were found sporadically in all processing steps followed. However, a decreasing trend was observed in Salmonella counts and Listeria spp. incidence during the processing. Thus, this study brings new valuable information on the dynamics of microflora during modern poultry processing.