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Measure  –  Consumption

Food animals

Here you find guidance, methods and tools to generate data on antibiotic consumption in food animals.

The World Organisation for Animal Health (WOAH, founded as OIE) has initiated a global data collection in animals and an increasing number of countries are able to report, though quality and completeness may differ. They have developed standards and guidelines to monitor the use of antibiotics in the animal sector. These are presented in the Terrestrial and the Aquatic Animal Health Codes.

Measure antibiotic consumption in animals

Antibiotic use data in the food animal sector can be obtained from farm animal records, veterinary prescriptions/records, pharmacies, distributors, or the pharmaceutical industry. If such sophisticated systems are not yet available, data can also be gathered through point prevalence or longitudinal studies on consumption at the farm level, which has been described by both AGISAR and European Surveillance of Veterinary Antimicrobial Consumption (ESVAC). In most countries, information on antibiotic consumption is obtained from sales data. In the European Union, ESVAC collects veterinary antibiotic sales data from member countries using a harmonized protocol, which is available at the ESVAC website. Similar programs and methods are often lacking in many low- and middle-income countries but the methods used by ESVAC can be applied globally.

Harmonization of data

In order to ensure uniformity of comparison, the sales data need to be linked to the animal demographics in each country. A population correction unit (PCU) has been developed for this purpose. The PCU is used as a proxy for the total live weight of food-producing animals within the country (number of livestock × estimated weight at treatment). In the EU, it only includes the main production animals. WOAH has developed a more global PCU, where animal species of relevance more globally are included.

However, the unit does not take into account that the antibiotic use differs between different animal species, and that different antibiotics have differences in potency and hence differences in dosage. There is therefore ongoing work to establish systems for the collection of standardized data, which includes data on antibiotic consumption per animal species, and sometimes weight group and production type.

Defined daily doses

ESVAC has proposed defined daily doses for animals (DDDvet) and defined course dose for animals (DCDvet) for antimicrobial veterinary medicinal products. By this, standardized fixed units of measurement for the reporting of data on consumption by species that take into account differences in dosing is provided.

  • The DDDvet is the assumed average dose per kg animal per species per day;
  • The DCDvet is the assumed average dose per kg animal per species per treatment course.

The units were developed on basis of average dose and duration of treatment in a number of EU countries. For national purposes, units based on national conditions may also be applicable. For an example of how to calculate number of DDDs from consumption data, see Humans. Standaridized units such as DDDvet however are difficult to interpret in settings where antibiotics are used for other reasons than treatment.

At farm level

At farm level, the treatment frequency and the number of treatment days, and the antibiotic compound used are relevant measures of antibiotic use in farm health programs and quality assurances schemes. In its simplest form, the number of treated animals per day during an observation period (preferably a production cycle) can be recorded. For more refined studies, a treatment unit (UDD, Used Daily Doses) has been defined as the administration of one active ingredient at its daily dose to one animal on one day. For the observed population (the farm) the number UDD can be calculated as the number of UDD under the observed period. To calculate the treatment frequency, the number of UDD is divided by the population size. As the population size in many farms vary during the year due to the production cycle, it is crucial to access information on the population size for each specific farm.

Resources below have been divided into the following tables:

  • Tools and guidelines
  • Databases and reports

One Health resources are found in Consumption.

Selected Resources

Tools and guidelines

Resources Description
WOAH Terrestrial Animal Health Code Guidelines. See for example Chapter 6.9: Monitoring of the quantities and usage patterns of antimicrobial agents used in food-producing animals.
The ‘Drug Bag’ method: lessons from anthropological studies of antibiotic use in Africa and South-East Asia Journal article presenting a non-verbal method for surveying antibiotic use at farms and in households. Investigates whether or not participants recognize pre-purchased antibiotics available in the study area. Participants are then asked to sort them, for example based on frequency of use. The method was tried-out in studies in Zimbabwe, Malawi, Myanmar, and Uganda. A drug bag questionnaire data collection form is available for download here (PDF, 0.3 MB).
WOAH Antimicrobial Resistance Information portal with information and resources from WOAH. See also the Annual Report on Antimicrobial Agents Intended for Use in Animals: 6th edition; template for reporting national data to the global database (Excel spreadsheet, 0.3 MB) and an annex to assist in calculations (PDF, 0.2 MB).
AACTING Guidelines Guidelines intended to assist establishment or revision of farm-level AMU monitoring systems. Particularly relevant for use in countries with established medicines registrations and regulations. An overview of existing monitoring systems in countries can be found here.
European surveillance of veterinary antimicrobial consumption (ESVAC) project Information portal with tools and database. ESVAC is a project within the European Medical Agency which collects information on antibiotic use in animals in the European Union (EU). A report on national sales data of antibiotics is published annually. ESVAC also provides an interactive database, sales data collection form and protocol.
Dairy antimicrobial usage calculator Tool to assist in calculating antibiotic use on dairy farms. The tool is a macro-enabled spreadsheet where heard and antibiotic use data are entered and gives consumption data as both mg/PCU and DDD. A benchmarking tool is also available at the same site.
Approaches for quantifying antimicrobial consumption per animal species based on national sales data: a Swiss example, 2006 to 2013 Journal article that has tested and describes three methods to estimate antimicrobial consumption on species level from veterinary sales data.

Databases and reports

Resource Description
Review of methods and metrics for studying human and livestock antibiotic use at the granular level Rapid scoping review that provides a range of available methods to collect antibiotic use data at the granular level in LMICs for humans and livestock health. The review revealed important gaps, particularly the very few protocols that have been designed to generate volume metrics.
Global trends in antimicrobial use in food animals Journal article. Effort to map global antibiotic consumption in livestock (228 countries). Projects that antimicrobial consumption in food animals will rise by 67% by 2030.
Review of Evidence on Antimicrobial Resistance and Animal Agriculture in Developing Countries Review that highlights evidence and knowledge gaps of antimicrobial resistance and use in agri- and aquaculture and identifies a lack of most evidence in low- and middle-income countries. See e.g. Annex 1 & 2 for literature review and reports on antibiotic use.

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