U.S. Department of Agriculture, Agricultural Research Service, 600 East Mermaid Lane, Wyndmoor, Pennsylvania 19038, USA.
J Food Prot. 2019 May;82(5):834-843. doi: 10.4315/0362-028X.JFP-18-430.
We surveyed chicken livers from various sources for the presence and levels of . The pathogen was recovered from 148 (59.4%) of 249 chicken livers purchased at retail stores in Delaware, New Jersey, and Pennsylvania over about a 9-month period. Positive samples harbored at levels of 6.4 most probable number (MPN)/g to 2.4 log CFU/g. The percentage of -positive livers purchased at retail outlets in New Jersey (72%, 59 of 82 livers) was significantly higher ( < 0.05) than the percentage for livers purchased in Delaware (48%, 36 of 75 livers); however, this percentage was not significantly different ( > 0.05) from that for livers purchased in Pennsylvania (57.6%, 53 of 92 livers). The pathogen was also recovered more often ( = 0.019) from livers that were packaged by retailers (81 of 121 livers, 66.9%) than from livers packaged directly by processors (67 of 128 livers, 52.3%). In related studies, 12 (5.8%) of 207 chicken livers harvested from birds on a research farm tested positive for at levels of 0.4 to 2.2 MPN/g. The recovery rate of was 4.4% (6 of 135 livers) from livers with the gall bladder attached and 8.3% (6 of 72 livers) from livers when the gall bladder was removed at harvest on the research farm. We also quantified the levels of a nine-strain cocktail (ca. 6.5 log CFU/g) of strains inoculated externally onto or internally into livers both before and after extended cold storage. Storage for at least 2 days at 4°C or 15 days at -20°C resulted in a decrease of about 1.0 log CFU/g in pathogen levels. Given the relatively high recovery rate (ca. 6.0 to 60.0%) and high (possibly illness causing) levels (0.4 MPN/g to 2.4 CFU/g) of associated with chicken livers in the present study, further interventions for processors are needed to lower the prevalence and levels of this pathogen on poultry liver.
我们调查了来自不同来源的鸡肝，以检测其存在情况和水平。在大约 9 个月的时间里，我们从特拉华州、新泽西州和宾夕法尼亚州的零售店购买的 249 个鸡肝中回收了 148 个（59.4%）。阳性样本中，的水平为 6.4 最可能数（MPN）/g 至 2.4 log CFU/g。在新泽西州的零售店购买的阳性鸡肝比例（72%，82 个中有 59 个）明显高于特拉华州（48%，75 个中有 36 个）；然而，与宾夕法尼亚州（57.6%，92 个中有 53 个）的比例没有显著差异（>0.05）。零售商包装的鸡肝中（121 个中有 81 个，66.9%）比加工商直接包装的鸡肝（128 个中有 67 个，52.3%）更容易回收（=0.019）。在相关研究中，从一个研究农场收获的 207 个鸡肝中，有 12 个（5.8%）的水平为 0.4 至 2.2 MPN/g。在研究农场收获时，胆囊未切除时的回收率为 8.3%（6 个中有 6 个，72 个中有 6 个）。我们还定量了在外部或内部接种了九株混合菌株（约 6.5 log CFU/g）的鸡肝在冷藏前和冷藏后的水平。在 4°C 下储存至少 2 天或在-20°C 下储存 15 天可使病原体水平下降约 1.0 log CFU/g。鉴于本研究中鸡肝中相对较高的回收率（约 6.0 至 60.0%）和高水平（可能致病）的（0.4 MPN/g 至 2.4 CFU/g），需要对加工商进行进一步干预，以降低家禽肝脏中这种病原体的流行率和水平。
