In this study we investigated the prevalence and location of Listeria monocytogenes and hygiene indicator bacteria on beef and pig carcasses. Carcasses were sampled after slaughter and before cooling at eight and nine sites on the carcass, respectively. For each sample, detection and enumeration of Listeria was performed, as well as the enumeration of Total Aerobic Counts (TAC) and Enterobacteriaceae. The L. monocytogenes isolates were also typed to determine pulsotypes and clonal complexes (CC). L. monocytogenes was detected on 46% [95% CI: 35–56%] of beef and 22% [95% CI: 11–32%] of pig carcasses. Contamination levels at the different carcass sites differed considerably between beef and pigs. Genetic typing of strains suggests that carcass contamination originates from both incoming animals with transmission during slaughter practices as well as persistent (CC9) contamination from the slaughterhouse environment. These findings can be used to understand the complexity of introduction and persistence of this pathogen in slaughter facilities. Accurate correlation of L. monocytogenes presence proved unfeasible with any of the tested hygiene indicator bacteria.

在这项研究中，我们调查了牛和猪car体中李斯特菌和卫生指示菌的流行和位置。屠宰后和冷却之前，分别在屠体的八个和九个位置取样。对于每个样品，都进行了李斯特菌的检测和计数，以及总有氧计数（TAC）和肠杆菌科的计数。该L.菌菌株也输入到确定pulsotypes和克隆物（CC）。单核细胞增生李斯特菌猪46体中有46％[95％CI：35–56％]和22％[95％CI：11–32％]的牛肉被检出。牛肉和猪的car体不同部位的污染水平差异很大。品系的遗传分型表明，contamination体污染既来自传入的动物，也来自屠宰过程中的传播，也来自屠宰场环境的持续性（CC9）污染。这些发现可用于了解这种病原体在屠宰场中的引入和持续存在的复杂性。单核细胞增生李斯特氏菌存在的准确关联被证明与任何测试的卫生指示剂细菌都不可行。