[The problem of a high content of vitamin A in the liver of calves, cattle, sheep and swine for the consumer. Amount of accumulation and mechanism of teratogenic effect (review article)].

Cases of hypervitaminosis A in men--especially in pregnant women, with development of malformations--are reported. The existence of withdrawal times to slaughter after the application of vitamin-A-containing preparations with a content of 10,000 to 10(6) international units and more is described. The content of vitamin A in the liver of monogastric animals is closely related to that in the feed. In ruminants about 40 to 70% of the vitamin A of the feed is decomposed by the microorganisms in the forestomachs. The amount of vitamin A stored in the liver after a therapeutic application is dependent of the initial content. The velocity of the depletion of the stores at a carotene- and vitamin-A-poor feeding is described. In ruminants and pigs in the account of the properties of the placenta no embryotoxicity of a therapeutic dose of vitamin A is to be expected. The mechanism of the teratogenesis by vitamin A in mice is described.