Purpose: The aim was to determine the effects of cafeteria diet (CD) and fish oil supplements given to pregnant and lactating rats on the birth weight and fatty acid profiles of their offspring.
Methods: Female rats were given standard diet (STD) or CD for 22 days before pregnancy. After mating, some animals remained on STD or CD; for some CD rats, the diet was supplemented with 8.78 % fish oil (CD-FO). After 12 days, half the CD-FO group returned to CD (CD-FO12) and the others remained on CD-FO.
Results: At birth, body weights of pups of the three CD groups were lower than STD, maintained until 21 days in the CD-FO group only. At the end of lactation, dams of the CD groups had increased plasma triacylglycerols (TAG), non-esterified fatty acids, and glycerol concentrations, whereas most n-6 long-chain polyunsaturated fatty acids (LCPUFA) were decreased, the effect being greatest in the CD-FO group, where most n-3 LCPUFA were increased and indices of Δ(5) and Δ(6) desaturase activities decreased. The 21-day-old pups of the CD group had increased plasma TAG, not present in the CD-FO group, which had increased 3-hydroxybutyrate concentrations. In both 2- and 21-day-old CD pups, plasma concentrations of ARA were lower than STD, and even lower in the two CD-FO groups.
Conclusions: The effect of CD and CD-FO decreasing pups body weight could be related to decreased concentrations of ARA, caused by the inhibition of the Δ(5) and Δ(6) desaturases in the pathway of n-6 LCPUFA biosynthesis.
Keywords: Arachidonic acid; Cafeteria diet; Dietary fish oil supplement; High-fat diet; Index of desaturases; Postnatal development.