Monogastric animals (excluding horses and rabbits) do not require Cobalt but they require vitamin B12. Consequently, there is no need for any cobalt supplementation to their feed. Therefore cobalt is removed from all poultry diets.

The FEEDAP Panel concludes that the potential cobalt supplementation to diets for ruminants, horses and rabbits should be maintained. A cobalt supplementation of 0.3 mg/kg DM and, taking into account cobalt background concentrations of feed material not exceeding 0.5 mg/kg DM of complete feed, a maximum content of 1 mg Co/kg complete feed is considered appropriate. For fish diets, the existing maximum content of 2 mg Co/kg complete feed should be maintained due to the higher cobalt background levels of fish meal, a major part of fish diets.

(EFSA Journal. Scientific Opinion on the use of cobalt compounds as additives in animal nutrition. EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP). 2009;7(12):1383, 16-17.)