Feed additive Vitamin d3 Crystal Vitamin d3 powder 

Feed additive Vitamin d3 Crystal Vitamin d3 powder  is a derivative of steroids and a general term for compounds with similar structures that have the ability to promote normal bone growth and maintenance. At present, it is known that there are at least ten sterol substances with vitamin D activity, of which only two are more important, known as pre vitamin D. One is ergosterol, also known as calciferol or ergocalciferol, which is produced by sunlight or ultraviolet radiation from plant oil or yeast. Another is 7-dehydrosterol, which exists in the skin and is converted into vitamin D3 under light, also known as cholecalciferol. The structures of D2 and D3 are very similar, both of which are B-ring opening derivatives of precursor sterols. The difference between the two is that there is an additional double bond and a methyl group on the side chain of vitamin D2. Vitamin D2 and D3 are colorless crystals, with corresponding m.p. values of 115-118 ℃ and 84-85 ℃. They are insolub…