Cobalt (Co) is an element that occurs only in a combined form in the earth’s crust. Together with other compounds, it has various application including rechargeable batteries, high performing alloys, as an oxidation catalyst, in making pigments, among other roles.
Vitamin B12 together with folate act as a cofactor of enzymes that participates in the metabolism of carbohydrates, fats, and amino acids as well as helps in forming and maintaining red blood cells, and healthy immunity system. Also, vitamin B12 is an appetite stimulant among other functions.
Therefore, cats do not require it to be supplemented so long as they have enough amount of cobalamin in their diets.
Other animals especially cattle may require supplementation of cobalt to avoid deficiency symptoms which are the same as those of cobalamin deficiency.