University College Dublin, School of Biosystems and Food Engineering, Belfield, Dublin 4, Ireland.
University College Dublin, School of Veterinary Medicine, Belfield, Dublin 4, Ireland.
Sci Total Environ. 2021 Sep 10;786:147474. doi: 10.1016/j.scitotenv.2021.147474. Epub 2021 Apr 30.
Farm-to-fork quantitative microbial risk assessments (QMRA) typically start with a preliminary estimate of initial concentration (C) of microorganism loading at farm level, consisting of an initial estimate of prevalence (P) and the resulting pathogen levels in animal faeces. An average estimation of the initial concentration of pathogens can be achieved by combining P estimates in animal populations and the levels of pathogens in colonised animals' faeces and resulting cumulative levels in herd farmyard manure and slurry (FYM&S). In the present study, 14 years of data were collated and assessed using a Bayesian inference loop to assess the likely P of pathogens. In this regard, historical and current survey data exists on P estimates for a number of pathogens, including Cryptosporidium parvum, Mycobacterium avium subspecies paratuberculosis (MAP), Salmonella spp., Clostridium spp., Campylobacter spp., pathogenic E. coli, and Listeria monocytogenes in several species (cattle, pigs, and sheep) in Ireland. The results revealed that Cryptosporidium spp. has potentially the highest mean P (P) (25.93%), followed by MAP (15.68%) and Campylobacter spp. (8.80%) for cattle. The P of E. coli is highest (7.42%) in pigs, while the P of Clostridium spp. in sheep was estimated to be 7.94%. C for Cryptosporidium spp., MAP., Salmonella spp., Clostridium spp., and Campylobacter spp. in cattle faeces were derived with an average of 2.69, 4.38, 4.24, 3.46, and 3.84 log MPN g , respectively. Average C of Cryptosporidium spp., Salmonella spp., Clostridium spp., and E. coli in pig slurry was estimated as 1.27, 3.12, 3.02, and 4.48 log MPN g , respectively. It was only possible to calculate the average C of Listeria monocytogenes in sheep manure as 1.86 log MPN g . This study creates a basis for future farm-to-fork risk assessment models to base initial pathogen loading values for animal faeces and enhance risk assessment efforts.
从农场到餐桌的定量微生物风险评估（QMRA）通常从农场一级微生物负荷的初步估计（C）开始，包括患病率（P）的初步估计和动物粪便中病原体的水平。通过结合动物群体中的 P 估计值、定植动物粪便中的病原体水平以及畜舍场厩肥和泥浆（FYM&S）中的累积水平，可以对病原体的初始浓度进行平均估计。在本研究中，使用贝叶斯推断循环整理和评估了 14 年的数据，以评估病原体的可能 P。在这方面，爱尔兰存在针对多种病原体的历史和当前调查数据，包括小隐孢子虫、牛分枝杆菌亚种副结核病（MAP）、沙门氏菌、梭菌、弯曲杆菌、致病性大肠杆菌和单核细胞增生李斯特菌，这些病原体存在于几种物种（牛、猪和羊）中。结果表明，小隐孢子虫具有最高的平均 P（P）（25.93%），其次是牛分枝杆菌（15.68%）和弯曲杆菌（8.80%）。猪的大肠杆菌 P 最高（7.42%），而绵羊的梭菌 P 估计为 7.94%。从牛粪便中获得的小隐孢子虫、MAP、沙门氏菌、梭菌和弯曲杆菌的 C 值平均分别为 2.69、4.38、4.24、3.46 和 3.84 log MPN g。估计猪粪中平均 C 值分别为 1.27、3.12、3.02 和 4.48 log MPN g。仅计算了绵羊粪便中单核细胞增生李斯特菌的平均 C 值为 1.86 log MPN g。本研究为未来的从农场到餐桌的风险评估模型提供了基础，以确定动物粪便中初始病原体负荷值，并加强风险评估工作。
