DOCOSAHEXAENOIC ACID IS TRANSFERRED THROUGH MATERNAL DIET TO MILK ANDTO TISSUES OF NATURAL MILK-FED PIGLETS

Docosahexaenoic acid (DHA) is incorporated in large amounts in structu ral lipids of the developing central nervous system. Milk DHA varies w ith maternal dietary DHA, but the effect of different intakes of DHA f rom milk on infant tissue fatty acids is unknown. The effect of milk h igh or low in DHA on the fatty acid composition of piglet brain, synap tic plasma membranes, retina, liver, plasma and RBC was studied. Pregn ant sows were fed diets with 2.5 g/100 g vegetable oil until 4 d pre-p artum and were then fed diets with 2.5 g/100 g soybean and canola oils or 4 g/100 g soybean oil plus 1 g/100 g fish oil to 15 d postpartum. Fish oil increased the milk DHA and eicosapentanoic acid from 0.1 to 1 .5% and from 0.2 to 0.4% of fatty acids, respectively, but did not alt er milk arachidonic acid. The level of DHA was significantly higher in plasma, liver and RBC phospholipids, brain and synaptic plasma membra ne of 15-d-old piglets fed milk with high DHA compared with low DHA. L iver, plasma and RBC, but not brain or retina arachidonic acid, was si gnificantly lower in piglets fed the high DHA milk compared with low D HA milk. Thus, differences in plasma, RBC and liver arachidonic acid a nd DHA of 15-d-old nursing piglets due to the maternal dietary fat wer e not accompanied by similar differences in central nervous system fat ty acids. These studies show maternal DHA intake determines in part th e infant plasma, RBC and liver phospholipid DHA. The results also sugg est milk with 0.1% of fatty acids as DHA may not support maximum depos ition of DHA in the brain of developing piglets.