Abstract

In this experiment, four hundred day-old broiler chicks were assigned randomly to 16 floor pens with 25 chicks each. Three diets containing 0% fish oil + 7% soybean oil, 3.5% fish oil + 3.5% soybean oil and 7% fish oil + 0% soybean oil and a free oil control diet were formulated. The birds fed fish oil diet showed a lower body weight than control group (P < 0.05). Abdominal fat percent in birds fed soybean oil and fish oil diets, were lower than control group (P < 0.05). The high density lipoprotein (HDL) concentration in birds fed fish oil diet was higher than other treatments, but the serum low density lipoprotein (LDL) decreased in birds fed fish oil diet (P < 0.05). The live weight of birds was positively correlated with glucose and LDL and negatively correlated with HDL concentrations (P < 0.01). The abdominal fat pad percent was positively correlated with triglyceride, glucose, LDL and very low density lipoprotein (VLDL) and a negative correlation was observed with HDL concentrations (P < 0.01). Triglyceride, cholesterol and VLDL concentrations were positively correlated with each other and a negative correlation was observed between high-density lipoprotein and low-density lipoprotein (P < 0.01). The results of the present study showed that higher fish oil inclusion in broiler diets can result in some unfavorable reduction in live weight and a beneficial influence on abdominal fat reduction.

Key words: Broiler chickens, fish oil, high-density lipoprotein, low-density lipoprotein.

Abbreviation

HDL, High density lipoprotein; VLDL, very low density lipoprotein;LDL, low density lipoprotein; TG, triglycerides; PUFA, polyunsaturated fatty acid;LPL,  plasma lipoprotein lipase.