اثر سطوح مختلف روغن ماهي روي عملكرد و ميزان اسيدهاي چرب كلسترول و تري كليسريد در بافت هاي انتخابي در جوجه هاي گوشتي

Effect of Fish Oil on Performance, Fatty Acid Composition, Cholesterol and Triglyceride Content of Selected Tissues in Broiler Chicks

This study was conducted to determine the effects of four different dietary levels of fish oil on performance, fatty acids composition, cholesterol and triglyceride in liver. breast and thigh muscle of broiler chicks. Two hundred and forty d-old male broiler chicks in a completely randomized design were allotted with four replicates. Broilers were fed isonitrogenous and isoenergetic diets containing O. I, 2 and 3% fish oil levels (treatments 1,2,3 and 4 respectively) ad-libitum in both starter (II to 21 d) and growth periods. During the final weekof the experiment (42 to 49 d) fish oil was removed from the diets. All of experimental groups were fed with the same diet to 10 d-old. The body weight gain, as well as feed efficiency were higher in broilers fed with fish oil as compared with control. The differences in feed intake were not significant. Thefarty acid profiles in tissues were altered by fish oil. The effects of different levels of Fa were not significant on cholesterol and triglyceride, except for the concentration of cholesterol in liver (p<0.05), that was lowered with 3% Fa. bUI after withdrawal of Fa from diet (49 days of age) the concentration of cholesterol and triglyceride significantly decreased in thigh and liver samples (p<0.05). Increased levels of fish oil clearly increased the amount of <0-3 and <0-6 polyunsaturated fatty acids in liver, breast an thigh muscle (p>0.05), and increased <0-6 linoleic acid only at 42 days of age which was significant in liver tissue. In conclusion, the addition of Fa in diet up to 2-3% and removing of Fa during the last weekand before slaughtering of the birds can be used for enrichment of meat.