Body lipids of guinea pigs exposed to different dietary fats from mid-gestation to 3 months of age. II. The fatty acid composition of the lipids of liver, plasma, adipose tissue, muscle and red cell membranes at birth.

Pregnant guinea pigs were fed one of three diets: a commercial low-fat diet, or a high-fat diet containing maize oil or beef dripping. The young were killed at birth and the fatty acid composition of the lipids of the liver, plasma, adipose tissue, quadriceps muscle and red cell membranes was determined. Compared with those fed the commercial diet the tissue of the young of mothers fed maize oil had an increased percentage of linoleic acid whereas in those of the young of mothers fed beef dripping, the percentage of oleic acid was significantly higher. These changes occurred both in the triglycerides and in the membrane phospholipids (with the exceptin of sphingomyelins) of all tissues examined. These results demonstrate that the fatty acid composition of the tissue lipids of the newborn guinea pig can be influenced by the fatty acid composition of the maternal diet. Changes in the fatty acid composition of membrane phospholipids can be as great as those in storage lipids. This raises the question of long-term physiological significance for the animal.