Effect of Source and Duration of Protected Fatty Acids Feeding, on Production Performance, Carcass Characteristics and Blood Metabolites in Fattening Lambs

This experiment was performed to investigate the effect of saturated and unsaturated fatty acids calcium salts (omega-3 and omega-9) on fattening performance, carcass traits and some blood biochemical properties of Lori Bakhtiari × Romanov male lambs.

49 male lambs with 29.97± 0.88 kg initial weight were divided into 7 equal groups, randomly. Lambs were fed individually with the following experimental diets: 1) Basal diet without fat powder (control), 2) Basal diet with fish oil calcium salts (2% of diet DM) for 90 days, 3) Basal diet with fish oil calcium salts (2% of diet DM) for 45 days, 4) Basal diet with olive oil calcium salts (2% of diet DM) for 90 days, 5) Basal diet with olive oil calcium salts (2% of diet DM) for 45 days, 6) Basal diet with saturated fat calcium salts (2% of diet DM) for 90 days and 7) Basal diet with saturated fat calcium salts (2% of diet DM) for 45 days. Daily feed intake of lambs was recorded and lambs body weight was measured weekly. At the end of the experiment, blood samples were taken from the jugular veins of the lambs. Then 28 lambs were weighed and slaughtered and were measured the weights of different parts of the lambs carcass.

Totally, feeding with calcium salts of fish oil, olive oil and saturated fats significantly increased daily weight gain and reduced the lambs feed conversion ratio compared to control group (p= 0.04). But had no significant effect on dry matter intake of the Lambs. Feeding with saturated and unsaturated calcium salts had no significant effect on serum glucose, cholesterol and triglyceride concentrations. Serum high density lipoproteins (HDL) were higher among the fat treatments than control treatment, but no significant difference was observed between fat treatments. The level of serum low density lipoproteins (LDL) when using of unsaturated fatty acids for 45 and 90 days was significantly lower than the using of saturated fat and control (p= 0.01). Lambs treated with fat powder had higher carcass yields than the control group. Feeding on fish and olive oil calcium salts reduced abdominal fat and kidneys around fat of lambs (p= 0.03).

Totally, results of this study showed that diet supplementation with fish and olive unsaturated fatty acids calcium salts increases the fattening performance and productivity of lambs.