Filippitzi Maria Eleni, Sarrazin Steven, Imberechts Hein, Smet Annemieke, Dewulf Jeroen
a Veterinary Epidemiology Unit, Department of Reproduction, Obstetrics and Herd Health, Faculty of Veterinary Medicine , Ghent University , Merelbeke , Belgium.
b Veterinary and Agrochemical Research Centre CODA-CERVA , Brussels , Belgium.
Food Addit Contam Part A Chem Anal Control Expo Risk Assess. 2016;33(4):644-55. doi: 10.1080/19440049.2016.1160442. Epub 2016 Mar 31.
The cross-contamination of non-medicated feed with residues of antimicrobials causes an animal and public health concern associated with the potential for the selection and dissemination of resistance in commensal bacteria and potentially zoonotic bacteria. To identify the extent of this situation, we built a risk model that provides a way to estimate the percentage of cross-contaminated feed in total and at the different levels at which cross-contamination may occur (i.e. the feed mill, the transport truck, the farm), for different levels of antimicrobial medicated feed produced in a country per year. The model, estimated that when antimicrobial medicated feed represents a hypothetical xi = 2% of the total feed produced in a country per year, then 5.5% (95% CI = 3.4%; 11.4%) of the total feed produced in a year could be cross-contaminated with different levels of antimicrobials due to practices related to medicated feed. In detail, 1.80% (95% CI = 0.2%; 7.7%) of the total feed produced in such a country would be cross-contaminated due to antimicrobial carryover occurring at the feed mill level, 1.83% (95% CI = 1.3%; 2.0%) at the transport truck level and 1.84% (95% CI = 1.2%; 2.0%) at the farm level. The model also demonstrated that even in cases where antimicrobial medicated feed would be produced in end-of-line mixers or a fine dosing system on trucks, the risk of cross-contamination would not be negligible; the percentage of cross-contaminated feed produced in a country (where xi = 2%) per year would be 3.7% (95% CI = 2.9%; 4.0%) and 2.4% (95% CI = 1.6%; 2.7%), respectively. It is hard to reduce the risk to zero as it is the result of factors occurring at different levels. Thus, the use of antimicrobial medicated feed should be avoided as much as possible to reduce selection pressure.
未添加药物的饲料被抗菌药物残留交叉污染，引发了动物和公共卫生方面的担忧，这与共生细菌和潜在人畜共患病菌中耐药性的选择与传播可能性相关。为确定这种情况的严重程度，我们构建了一个风险模型，该模型提供了一种方法，可针对一个国家每年生产的不同水平的抗菌药物添加饲料，估算交叉污染饲料在总量中以及在可能发生交叉污染的不同环节（即饲料厂、运输卡车、养殖场）中所占的百分比。该模型估计，当抗菌药物添加饲料占一个国家每年生产的饲料总量的假设比例xi = 2%时，由于与添加药物饲料相关的操作，一年中生产的饲料总量的5.5%（95%置信区间 = 3.4%；11.4%）可能会被不同水平的抗菌药物交叉污染。详细而言，在这样一个国家生产的饲料总量中，1.80%（95%置信区间 = 0.2%；7.7%）会因饲料厂层面的抗菌药物残留而被交叉污染，运输卡车层面为1.83%（95%置信区间 = 1.3%；2.0%），养殖场层面为1.84%（95%置信区间 = 1.2%；2.0%）。该模型还表明，即使在抗菌药物添加饲料是在生产线末端混合器或卡车上的精细配料系统中生产的情况下，交叉污染的风险也不可忽视；一个国家（其中xi = 2%）每年生产的交叉污染饲料的百分比将分别为3.7%（95%置信区间 = 2.9%；4.0%）和2.4%（95%置信区间 = 1.6%；2.7%）。由于这是不同层面多种因素导致的结果，很难将风险降至零。因此，应尽可能避免使用抗菌药物添加饲料，以降低选择压力。
