The use of antimicrobials in livestock constitutes an increasing global concern, and many countries pursue approaches to reduce the amount used, particularly in the pig production industry. The EU Commission has decided, due to environmental concerns, to phase out use of zinc oxide in pigs by 2022. This poses an additional challenge to efforts to reduce antimicrobial use (AMU) in European pig production. The pig production sector needs further information about how to comply with official AMU requirements without losing competitiveness. The most efficient approaches are likely to involve a combination of multiple factors. Therefore, the objective of this study was to explore multidimensional associations between biosecurity, productivity, vaccination and AMU. A cross sectional study was conducted using data from 160 Danish sow herds in 2014-2015. Biosecurity data were collected through computer-assisted telephone interviews using a pre-developed questionnaire (Biocheck.UGent®) supplemented with additional country-specific questions and translated into Danish. Herd-specific data, consisting of antimicrobial prescriptions, purchase of vaccines against five endemic infections, herd health status and one productivity measure (i.e. number of weaned piglets per sow per year) were extracted from various databases. Factor analysis was conducted on a subset of the data from 152 herds with sufficiently complete data. The identified factors were explained by evaluating data from herds with extreme loadings on the respective factor. The results were further discussed based on plots combining herd factor loadings on two factors at a time. Four factors were selected based on the break-point in the scree-plot. Factor 1 included herd type, herd size, and age of farm buildings. Factor 2 covered general biosecurity, including several internal and external biosecurity measures. Factor 3 represented preventive measures implying specific focus on avoiding introduction of ASF by foreign employees. Lastly, Factor 4 covered vaccination status, specifically regarding vaccination against Mycoplasma hyopneumoniae and Porcine Reproductive and Respiratory Syndrome virus. These factors were used to group the 152 sow herds into herd typologies. Feasible strategies aimed at improving health by reducing AMU without hampering animal welfare were identified and discussed for each typology. AMU and productivity correlated only weakly with other variables. This is probably due to limited variability in both these variables in study herds, which might be attributed to official restrictions on AMU, and a general high level of health and biosecurity in Danish sow herds.

中文翻译：

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牛群类型基于对丹麦母猪群的生物安全性，生产率，抗菌素和疫苗使用数据的多变量分析。

在家畜中使用抗菌剂已成为全球关注的焦点，许多国家都在寻求减少使用量的方法，特别是在养猪业。出于环境方面的考虑，欧盟委员会已决定在2022年前逐步淘汰生猪中的氧化锌。这对减少欧洲生猪生产中的抗菌剂使用量提出了新的挑战。生猪生产部门需要有关如何遵守官方AMU要求而又不丧失竞争力的更多信息。最有效的方法可能涉及多个因素的组合。因此，本研究的目的是探讨生物安全性，生产率，疫苗接种与AMU之间的多维关联。使用2014-2015年间160头丹麦母猪的数据进行了横断面研究。通过使用预先开发的调查表（Biocheck.UGent®）补充了特定于国家/地区的其他问题，通过计算机辅助电话采访收集了生物安全数据，并将其翻译成丹麦文。从各种数据库中提取特定于畜群的数据，包括抗菌药处方，购买针对五种地方性感染的疫苗，畜群健康状况和一项生产率指标（即，每头母猪断奶仔猪的数量）。对来自152个牛群的数据子集进行了因子分析，并获得了足够完整的数据。通过评估来自各个因素的极端负荷的畜群数据来解释已识别的因素。基于将牧群因子负载一次组合在两个因子上的图，进一步讨论了结果。根据卵形图中的断点选择了四个因素。因素1包括畜群类型，畜群大小和农舍的年龄。因素2涵盖了一般生物安全性，包括一些内部和外部生物安全措施。因素3代表了预防措施，暗示着特别着重于避免外国雇员引入ASF。最后，因子4涵盖了疫苗接种状况，尤其是针对猪肺炎支原体和猪繁殖与呼吸综合征病毒的疫苗接种。这些因素用于将152个母猪群分为不同的群型。针对每种类型，确定并讨论了旨在通过减少AMU而不损害动物福利来改善健康的可行策略。AMU和生产率与其他变量之间的相关性很小。