Dietary safflower phospholipid reduces liver lipids in laying hens

This experiment was conducted to determine the effects of dietary safflower phospholipids (crude safflower phospholipid and purified safflower phospholipid) on performance and lipid metabolism of laying hens. Sixty-week-old Single Comb White Leghorn laying hens were divided into four groups of seven birds each, and were given one of four experimental diets containing 5% beef tallow (served as a control, tallow), a mixture of safflower oil and palm oil (SP-oil), crude safflower phospholipid (Saf-PLcrude), or purified safflower phospholipid (Saf-PL) for 7 wk. Egg production ratio and daily egg mass were significantly higher in hens fed Saf-PLcrude diets than in hens of the other diet groups. There were no significant differences in egg weight among groups. Liver cholesterol and triglyceride contents were significantly decreased in all treated groups as compared with the control. The activity of hepatic 3-hydroxy-3 methylglutaryl coenzyme A reductase was the highest in hens fed the Saf-PLcrude diet. Serum esterified cholesterol concentration was decreased by feeding of SP-oil, Saf-PLcrude, or Saf-PL diets. Serum lecithin-cholesterol acyltransferase activity was highest in hens fed the tallow diet. Excreta neutral steroid excretion was significantly increased in the Saf-PLcrude or Saf-PL diet groups, although acidic steroid excretion was not affected by dietary treatments. Total cholesterol, triglyceride, and phospholipid contents in egg yolks were not different for any dietary treatments. The fatty acid compositions of egg yolks from hens fed Saf-PLcrude diets were not different with those fed the SP-oil diet, although eggs of hens fed the Saf-PL diet showed lower total polyunsaturated fatty acids. These results suggest that dietary safflower phospholipids may be a valuable ingredient to layers for reducing liver triglycerides and serum cholesterol without any adverse effects.