Changes in the levels of certain vitamins from B group under conditions of vitamin deficiency

In experiments on rabbits the levels of vitamins B1, B2, B6, PP and pantothenic acid were determined to establish the grade and the sequence of their disappearance from the blood and liver in states of exogenous and endogenous vitamin deficiency. The experiments were carried out in which vitamin deficiency was produced by removing vitamins from the diet or by giving the rabbits antibiotics of different activity spectrum when the animals were kept on a diet without vitamins. Determinations of vitamin levels were performed using microbiological methods. It was found that the time after which changes in vitamin levels developed as well as the intensity of changes differ, depending on the experimental model used, but the sequence of vitamin disappearance from the organism is always the same. The first to disappear were vitamins B1, followed by vitamin B6 and pantothenic acid.