In dairy herds, application of antimicrobials at drying-off is a common mastitis control measure. This article describes a protocol for systematic review and meta-analysis to address three crucial points regarding antimicrobial usage at drying-off: (1) comparative efficacy of antimicrobials used for preventing new and eliminating existing intramammary infections (IMI); (2) comparison of selective and blanket dry cow therapy approaches in preventing new and eliminating existing IMI; and (3) assessment of the extra prevention against new IMI that can be gained from using antimicrobial-teat sealant combinations versus antimicrobials alone. Five PICO (Population, Intervention, Comparator, Outcome) questions were formulated to cover the three objectives of the review. Medline, CAB s, Web of Science, and conference proceedings will be searched along with iterative screening of references. Articles will be eligible if: (1) published after 1966; (2) written in English or French; and (3) reporting field clinical trials and observational studies, conducted on dairy cows at drying-off, with at least one antimicrobial-treated group and one IMI-related outcome. Authors will independently assess the relevance of titles and abstracts, extract data, and assess bias and the overall quality of evidence. Results will be synthesized and analyzed using pairwise and network meta-analysis. The proposed study will significantly update previously conducted reviews.

中文翻译：

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用于治疗和预防乳房内感染的基于抗菌素的干奶牛治疗方法：系统评价和荟萃分析方案

在奶牛群中，在干燥时使用抗菌剂是一种常见的乳腺炎控制措施。本文描述了系统评价和荟萃分析的方案，以解决关于干燥时抗菌素使用的三个关键点：（1）用于预防新的和消除现有乳房内感染（IMI）的抗菌剂的比较功效；(2) 在预防新的和消除现有的 IMI 方面的选择性和毯式干奶牛治疗方法的比较；(3) 评估使用抗菌剂-乳头密封剂组合与单独使用抗菌剂相比对新 IMI 的额外预防。制定了五个 PICO（人口、干预、比较者、结果）问题以涵盖审查的三个目标。Medline, CAB s, Web of Science, 会议论文集将与参考文献的迭代筛选一起被搜索。符合以下条件的文章将符合条件： (1) 1966 年之后发表；(2) 用英文或法文书写；(3) 报告在干奶时对奶牛进行的现场临床试验和观察性研究，其中至少有一个抗生素治疗组和一个 IMI 相关结果。作者将独立评估标题和摘要的相关性，提取数据，评估偏倚和证据的整体质量。结果将使用成对和网络荟萃分析进行综合和分析。拟议的研究将显着更新先前进行的审查。在干奶时对奶牛进行，至少有一个抗菌治疗组和一个与 IMI 相关的结果。作者将独立评估标题和摘要的相关性，提取数据，评估偏倚和证据的整体质量。结果将使用成对和网络荟萃分析进行综合和分析。拟议的研究将显着更新先前进行的审查。在干奶时对奶牛进行，至少有一个抗菌治疗组和一个与 IMI 相关的结果。作者将独立评估标题和摘要的相关性，提取数据，评估偏倚和证据的整体质量。结果将使用成对和网络荟萃分析进行综合和分析。拟议的研究将显着更新先前进行的审查。