Aim. To investigate the vitamin D status in highly productive cows during winter housing period and effect of cholecalciferol by various ways of vitamin D 3 injection to cows in last days of gestation and after calving. Methods. Enzyme-linked immunoassay, spectrophotometry. Results. It has been stated that intramuscular injection of cholecalciferol into cows caused increase of the vitamin D 3 active metabolite – 25-OHD 3 , calcium, phosphorus and magnesium levels together with decrease of alkaline phosphatase level in pre- and post-natal periods. Oral supplementation makes little infl uence on the studied blood parameters of cows. Conclusions. Extrabuccal administration and oral supplementation of cholecalciferol in winter housing period to high-yield cows in the last days of gestation and after calving is accompanied by increased levels of its metabolites and their effect on mineral metabolism in the postnatal period. The nature of these changes depends on the mode of vitamin D administration and the
physiological state of the cows.
Solid-Phase Total Synthesis of Dehydrotryptophan-Bearing Cyclic Peptides Tunicyclin B, Sclerotide A, CDA3a, and CDA4a using a Protected β-Hydroxytryptophan Building Block