Panbonis® (1,25(OH)2D3 – glycosides) is the unique source of the bioactive form of vitamin D3, produced by Solanum glaucophyllum.
Being a source of the bioactive form of vitamin D3, 1,25(OH)2D3 – gly does not need activation in the liver or the kidney.
The glycosidic bonds of 1,25(OH)2D3-gly are gradually cleaved in the intestine. Subsequently, 1,25(OH)2D3 is absorbed and immediately functional. Because 1,25(OH)2D3 content in blood is regulated by enzymatical inactivation, it is safe up to 20x overdose.
The synthesis and inactivation of 1,25(OH)2D3 is regulated by feedback mechanisms on the activity of 1α-hydroxylase, controlled by different hormones and 1,25(OH)2D3, and by Ca and P levels in blood, to maintain Ca homeostasis.
By including Panbonis®, the serum level of 1,25(OH)2D3 is increased during critical periods, preventing low serum Ca levels that normally occur in e.g. the onset of milk production or egg production. In dairy cows such a reduction in serum Ca can result in (sub-)clinical milk fever.
Fat soluble vitamin D3 (parent form) and 25(OH)D3 (circulating form) can be stored in body fat. In contrast, 1,25(OH)2D3 is neither stored in body tissues nor translocated in offspring.
Therefore, there is no upper limit established by EFSA for Panbonis® contents in feed, in contrast with vitamin D3 and 25(OH)D3.
