Maternal lipid intake during pregnancy and lactation alters milk composition and production and litter growth in rats

The relationship between dietary fat content and milk composition, production and litter growth was studied in rats fed during pregnancy and lactation purified diets of equal energy density containing 2.5 or 20 g fat/100 g diet. A subsample of rats (HL-EP group) fed the high lipid (HL) diet but paired on an energy basis with the low lipid (LL) diet group was also studied in a separate experiment. Food intake, dam body weight and litter weight were recorded daily. Rats were milked on d 14 of lactation. Milk lipid, lactose and protein concentration and milk production were measured. lactating rats fed the HL diet had significantly higher energy intakes (P 0.01) and milk production (P 0.05) than rats fed the LL diet. Milk lipid concentration and daily milk volume and lipid production were significantly higher in the HL group. The HL-EP dams had significantly higher milk lipid, protein and lactose concentrations (P 0.05) and tended to have higher daily lipid and energy outputs (P