Epidemiology Research Unit, Department of Veterinary and Animal Science, Northern Faculty, Scotland's Rural College, Inverness, Scotland, IV2 5NA, UK.
Scottish Government's Centre of Expertise on Animal Disease Outbreaks (EPIC).
Vet Rec. 2021 Jul;189(1):e28. doi: 10.1002/vetr.28. Epub 2021 Jan 21.
Accurate estimation of antimicrobial use (AMU) is important in assessing reduction of agricultural AMU. This cross-sectional study aimed to evaluate several approaches for estimating AMU at the herd level and to report on AMU for beef and dairy farms in Scotland.
Pharmaceutical sales data for 75 cattle herds (2011-2015) were screened for antimicrobial products and aggregated by herd and year. Several denominators for usage estimates were calculated and compared for their suitability at the herd level.
The median total mass of active ingredient sold per kg of bovine livestock was 9.5 mg/kg for beef herds and 14.3 mg/kg for dairy herds. The 'highest priority critically important' antimicrobials (HPCIA) were by total mass of active ingredient, 10.6% of all sales; by total defined daily dose veterinary (DDDVet), 29.8% and by DCDvet, 20.0%. These are the first estimates of AMU for beef cattle in the UK, and for cattle of any kind in Scotland. Estimates of herd-level usage based on population correction unit (PCU) were sensitive to low values for PCU for specific herd-years due to their demographic composition.
Pharmaceutical sales data can provide useful estimates of AMU, but estimating usage per PCU is not appropriate for comparing groups of cattle with different demographic compositions or for setting herd-level targets. Total mass of active ingredient per kilogram of livestock is more stable and hence suitable than PCU-based methods for assessing AMU at the herd level.
准确估计抗菌药物使用量（AMU）对于评估减少农业 AMU 非常重要。本横断面研究旨在评估几种估算 herd 水平 AMU 的方法，并报告苏格兰肉牛和奶牛场的 AMU 情况。
筛选了 75 个牛群（2011-2015 年）的药物销售数据，以确定抗菌药物产品，并按 herd 和年份进行汇总。计算了几种使用率估算的分母，并比较了它们在 herd 水平上的适用性。
肉牛 herd 的牛只存栏量每公斤销售的活性成分总量中位数为 9.5 毫克/公斤，奶牛 herd 为 14.3 毫克/公斤。按活性成分总量计，“高优先级关键抗菌药物”（HPCIA）占所有销售额的 10.6%；按总兽医定义日剂量（DDDVet）计，占 29.8%；按 DCDvet 计，占 20.0%。这是英国首次对肉牛的 AMU 进行估算，也是苏格兰首次对任何种类的牛的 AMU 进行估算。基于群体校正单位（PCU）的 herd 水平使用率估算对特定 herd-year 的 PCU 值较低较为敏感，因为它们的人口构成不同。
药物销售数据可以提供有用的 AMU 估算，但基于 PCU 的使用率估算不适合比较具有不同人口构成的牛群，也不适合设定 herd 水平的目标。每公斤牲畜的活性成分总量比基于 PCU 的方法更稳定，因此更适合评估 herd 水平的 AMU。
