Maternal Diet Fatty Acid Composition Affects Neurodevelopment in Rat Pups1–4

Abstract

The effect of pre- and postnatal maternal dietary fatty acid composition on neurodevelopment in rat pups was studied. Timed pregnant dams were fed, beginning on d 2 of gestation and throughout lactation, either nonpurified diet (reference) or a purified diet whose fat source (22% of energy) was either corn oil or menhaden fish oil. On postnatal d 3, pups were randomly cross-fostered among dams of the same diet group and culled to 10 pups per dam. Milk was removed from stomachs of culled pups for fatty acid analyses. From postnatal d 4 to 30, pups were assessed daily for the appearance of neurodevelopmental reflexes. Auditory brainstem conduction times were measured on postnatal d 23 and 29. Pups were killed on postnatal d 30, and cerebrums were removed for fatty acid analyses. The fatty acid composition of maternal milk and pup cerebrums reflected maternal diet with higher levels of (n-3) and (n-6) fatty acids in the fish oil and corn oil groups, respectively. The time of appearance of auditory startle was significantly delayed (P = 0.004), and auditory brainstem conduction times on postnatal d 23 and 29 were significantly longer in pups of the fish oil– than corn oil–fed dams (P ≤ 0.05). A delay in the appearance of the auditory startle reflex and longer auditory brainstem conduction times in pups of dams fed fish oil–supplemented diet may be due to negative effects on myelination of the auditory brainstem pathway.