Verbelchuk , T., Verbelchuk , S., Kovalchuk , I., Kovalchuk , I., Vasiliev , R. and Klim , V. 2021. Balance of ferum and copper in the organs of pigs when using non-traditional natural additives. Bulletin of Sumy National Agrarian University. The series: Livestock. 2 (45) (May 2021), 77-82. DOI:https://doi.org/10.32845/bsnau.lvst.2021.2.11.