Livestock counts and slaughter statistics

Animal biomass as denominator was calculated according to OIE methodology with some modifications (1,2). Modifications included using a standard sow weight of 220 kg, instead of 192 kg for Africa, as South African sows are heavier (3). The OIE also includes a conversion factor of 0.09, as it is the anticipated proportion of sows present in the pig population, but this factor was omitted as the number of sows present on the farm was known. The final equation used to calculate the animal biomass per year is shown below: <br> Animal biomass (year) (kg) = Sum of live weight of all pigs slaughtered + (average sow population x 220 kg) <br> The total live weight of all pigs slaughtered per month was recorded by the farmer. These monthly values were summed to obtain the total live weight of all pigs slaughtered (kg) per year. The monthly livestock counts were used to obtain the yearly average number of sows present on the farm. <br> <strong>References: </strong> 1. OIE. <em>Annex to the guidance for completing the OIE template for the collection of data on antimicrobial agents for use in animals: Considerations on converting content of antimicrobial active ingredients in veterinary medicines into kilograms</em>. (2020). Available online at: https://www.oie.int/fileadmin/Home/eng/Our_scientific_expertise/docs/pdf/AMR/2020/ENG_AMUse_Annex_to_Guidance_Final_2020.pdf (accessed February 22, 2021) 2. Góchez D, Raicek M, Pinto Ferreira J, Jeannin M, Moulin G, Erlacher-Vindel E. OIE Annual report on antimicrobial agents intended for use in animals: Methods used. <em>Front Vet Sci</em>. (2019). 6:317. doi: 10.3389/fvets.2019.00317 3. BFAP. <em>Evaluating the South African pork value chain</em>. (2013). Available online at: http://www.bfap.co.za/wp-content/uploads/reports/BFAP Pork value chain 2013_Final.pdf (accessed July 20, 2021)