Since vitamin B12 has important metabolic functions, but is unable sufficiently to synthesize into organisms of domestic animals (especially non-ruminants), special attention is given to adding B12 into feed. The needs for this vitamin are provided through vitamin premixes, so determining the quantity of B12 in the samples is of utmost importance. When standard chemical methods are applied extraction and purification are required. In this paper is described a method where the content of B12 in premix with high level of different vitamins is determined through an indirect method: measuring the level of cobalt using atomic absorption spectrophotometry. The content of B12 was determined from the content of cobalt. The obtained results show that in the samples of pure B12 vitamin (used as an additive to feed) the measured values were lesser than 2% comparing to the expected values. In vitamin premixes the measured values of group B and vitamin premixes of vitamin B group and other (A, D, E) vitamins, the measured values differed from those given on the declaration, and the difference was lesser than 5%. The obtained results point that determining vitamin B12 by measuring cobalt content using AAS method is a fast, accurate and simple method that can be applied in examining all the feed samples.
Arhives of Veterinary Medicine is an Open Access Journal.