Olive Cake and Barley Malt Rootlets in Hen Diets to Improve Egg Lipids and Fatty Acids

The aim of the present study was to investigate the possibility of improving egg lipids and fatty acids com-position of laying hens through inclusion of olive cake plus barley malt rootlets in the diets. Seventy, 54-week-old, Lohman laying hens were fed for a 12 weeks laying period on 3 iso-caloric and iso-nitrogenous diets contained 0 (control), 28.5 g olive cake (OC) + 25.5 g barley malt rootlets (BMR), 28.5 g OC + 51.1 g BMR, 57.0 g OC + 25.5 g BMR or 57.0 g OC + 51.1 g BMR per kg. All the tested diets decreased plasma cholesterol (P < 0.05) and triglycerides (TG) (P < 0.001) and yolk concentrations (P < 0.0001) of total lipids, TG, cholesterol, low-density lipoproteins and phospholipids. Inclusion of OC plus BMR in the diets at 28.5 g OC + 25.5 g BMR, 28.5 g OC + 51.1 g BMR, 57.0 g OC + 25.5 g BMR or 57.0 g OC + 51.1 g BMR per kg decreased concentration of total saturated fatty acids (SFA) of egg yolk by 22.4, 50.1, 58.5 and 55.4%, respectively and increased total polyunsaturated fatty acids (PUFA) (2.4, 1.4, 2.1 and 1.2 fold, respectively) and total n-6 PUFA (2.5, 1.9, 2.7 and 1.9 fold, respectively). Total monounsaturated fatty acids (MUFA) were decreased by 8.1% with dietary 28.5 g OC + 25.5 g BMR per kg diet, while it was increased by 105, 93.4 and 128.5% with dietary 28.5 g OC + 51.1 g BMR, 57.0 g OC + 25.5 g BMR and 57.0 g OC + 51.1 g BMR per kg, respectively. To feed laying hens with rations that contained 28.5 g OC + 25.5 g BMR, 28.5 g OC + 51.1 g BMR and 57.0 g OC + 25.5 g BMR per kg diet increased yolk concentrations of total n-3 PUFA (217, 4.9 and 57.5%, respectively), while ration with 57 g OC + 51.1 g BMR per kg on the diet de-creased it by 56.5% compared to the control. It is concluded that inclusion of OC at rate of 28.5 or 57.0 g/kg on the diet in combination with BMR at rate of 25.5 or 51.1g BMR g/kg on the diet of laying hens decreased cholesterol and SFA with great increases I n MUFA and moderate increases in n-3 PUFA in egg yolk lipids.