If you blame the varying availability of cobalt in nature on "modern farming practises" I think that's wrong.mediocrity511 wrote: ↑Thu Jan 09, 2020 10:01 am... I quite specifically mentioned "commercially farmed animals". Worth pointing out that humans used to also receive some of their b12 from vegetables grown in "night soil". The point is that modern farming practises mean we either need to supplement ourselves with b12 or we need to provide sources for animals to supplement themselves.
see f.ex. Cobalt in soils.
Snippet:
Modern farming is surely not to blame for such problems.Why is cobalt added to some soils?
Due to problems associated with cobalt deficiency in agricultural soils, the behaviour of cobalt entering, and within, soils has been studied for a number of years. A lack of cobalt in a form which plants or earth dwelling organisms are able to absorb can have major effects on the health of the wildlife in an area. A classic example of this is the “Nova Scotia Moose Mystery” (Frank et al. 2004), where moose in Eastern North America were observed to have a wasting debilitating disease. It was found to be related to inadequate levels of bioavailable cobalt in their diet. The authors concluded that cobalt salt licks should be introduced in limited areas of Nova Scotia to balance the moose’s diet and restore them to health.
Bioavailable cobalt in soil is also necessary for the healthy functioning of some plants. This is especially true for leguminous plants, with cobalt being an essential nutrient for the micro-organisms which fix atmospheric nitrogen in the plants’ root nodules (Gad 2002).