Alteration of plasma folates in gestating sows and newborn piglets. Natsuhori, Masahiro, Minoru Shimoda, and Ei-Ichi Kokue. Department of Veterinary Medicine, Faculty of Agriculture, Tokyo University of Agriculture and Technology, Fuchu, Tokyo 183 Japan
APStracts 2:0214R, 1995.
Plasma folates (tetrahydrofolate, THF; N5-methyltetrahydrofolate, 5MF) were determined in non-gestating, gestating and lactating sows (2 to 4 years old, 2 to 6 parities, n = 88), and in newborn, growing, and finishing pigs (0 to 158 days old, n=191) by using high-performance liquid chromatography with an electrochemical detector. Plasma folates after folic acid injection (1 mg/kg, i.v.) were also monitored in 2 day, 2 week, and 2 month old pigs. In sows, plasma folates decreased significantly as pregnancy advanced. This was mainly due to the decrease of THF, which must be caused by the folate supply from maternal body to the fetuses. In newborn piglets, levels of "total" plasma folates were much higher than those in adults (non-gestating sows), and 5MF was the major folate content. This result may be related to the observation that after folic acid injection newborn piglets showed much higher metabolic activity of folic acid to 5MF than adults. Rapid and drastic decrease of plasma folate was observed during nursing in piglets, which is considered to be associated with the decrease of the metabolic activity of folic acid and rapid expansion of body volume together with negative folate intake during nursing period.

Received 13 December 1994; accepted in final form 6 July 1994,
APS Manuscript Number R705-4.
Article publication pending Am. J. Physiol. (Regulatory Integrative
Comp. Physiology).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 10 August 1995.