MATERNAL DIET FATTY-ACID COMPOSITION AFFECTS NEURODEVELOPMENT IN RAT PUPS

The effect of pre-and postnatal maternal dietary fatty acid compositio n on neurodevelopment in rat pups was studied. Timed pregnant dams wer e 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 a nd 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 ass essed daily for the appearance of neurodevelopmental reflexes. Auditor y brainstem conduction times were measured on postnatal d 23 and 29. P ups were killed on postnatal d 30, and cerebrums were removed for fatt y acid analyses. The fatty acid composition of maternal milk and pup c erebrums reflected maternal diet with higher levels of (n-3) and (n-6) fatty acids in the fish oil and corn oil groups, respectively. The ti me 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 d ams (P less than or equal to 0.05). A delay in the appearance of the a uditory 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.