The Teratogenic Effect of Vitamin a Deficiency in Pigs

Abstract

In connection with experiments concerning the utilization of perorally and parenterally administered vitamin A in pigs and the transfer of this vitamin from the mother to the fetuses investigations were performed concerning the teratogenic effect of vitamin A deficiency in this animal. 9 sows and gilts which throughout the pregnancy or in the first third of this were depleted of vitamin A gave birth to 91 piglets all of which had malformations cf. Table 1. The most frequent anomaly was microphthalmia; of other characteristic malformations may be mentioned heart defects, diaphragmatic hernia, malformed and not ascended kidneys, underdevelopment of genital organs, internal hydrocephalus and herniations of the spinal cord. Of this syndrome of malformations only one, namely the herniations of the spinal cord, seems to be specific for vitamin A deficiency. This malformation may be due to retarded growth of the bone tissue in relation to the relative normal growth of the nerve tissue. I forbindelse med forsøg over udnyttelsen af parenteralt og peroralt appliceret A-vitamin til svin samt overførsel af dette vitamin fra so til fostre blev der foretaget undersøgelser over A-vitaminmanglens teratogene effekt. 9 gylte og søer, der under hele drægtigheden eller i den første trediedel af denne, var fuldstændig udtømt for A-vitamin, fik ialt 91 grise, der alle udviste misdannelser, jvfr. tabel 1. Den hyppigst forekommende anomali var mikrophthalmi. Af andre karakteristiske misdannelser kan nævnes hjertedefekter, diafragmabrok, manglende ascenxiering af misdannede nyrer, underudvikling af kønsorganer samt intern hydrocephali og rygmarvsprotrusioner. Efter den komparative litteratur at dømme synes kun en enkelt af dette syndrom af misdannelser, nemlig rygmarvsprotrusionerne, at være specifik for A-vitaminmanglen. Denne misdannelse skyldes sandsynligvis en forsinket vækst af knoglevævet i forhold til den relativt normale vækst af nervevævet.