Effects Of Conjugated Linoleic Acid On Growth Performance,Carcass Quality And Immune Function Of Broiler Chickens

Conjugated linoleic acid (CLA) is a mixture of geometric and positional isomers of linoleic acid. An experiment was conducted to examine the effects of CLA diets on the growth performance, slaughter parameters, meat quality, intramuscular fat content, serum lipid content, fat cell size and immunity parameters in Yellow broiler chickens in order to study the effect mechanism of dietary CLA on fat accumulation. A total of 90 (half male and half female) one-day-old Yellow broiler chickens were allocated to three dietary treatments of 30 chickens each with different inclusion level of CLA (0%, 1% and 3%CLA) and were fed for 49 days. 12 chichens were slaugtered in each group on day 21 and day 49 respectively. Slaugter parameters, intramuscular fat of breast muscle and leg muscle, drip loss, cooking loss, abdominal fat, fat cell size, thymus index, cloacal bursa index, spleen index were measured. Blood samples were collected from the vena jugularis total. Cholesterol, triacylglycerol, HDL cholesterol, LDL cholesterol, free fatty acid concentration, hormone level and ND titers cava were evaluated in serum. Body absolute weights, average daily gain, average day feed intake and the ratio of feed to gain of all broilers were determined at the beginning and end of the experiment. The results as fellows:There was no difference in growth performance among treatments. Abdominal fat rate was reduced respectively by 28.01% and 21.96% (P<0.05) for 3% CLA and 1% CLA. Other slaughter parameters on d 49 and slaughter parameters on d 21 were unaffected by CLA. Dietary CLA improved meat color and water holding capacity was significantly enhanced (P<0.05). Intramuscular fat of leg muscle and breast muscle was significantly increased for 3% CLA groups (P<0.05). Serum triacylglycerol and HDL cholesterol concentration was significantly reduced (P<0.05). FFA concentration was significantly increased (P<0.05). Total serum cholesterol and LDL cholesterol concentration was unaffected. And fat cell diameter was significantly reduced (P<0.05). Serum Leptin and adiponectin level on d 49 was unaffected. Thymus index and cloacal bursa index on d 49 was significantly increased (P<0.05). There was no difference in anti-NDV antibody titers, spleen index on d 49 and immunity parameters on d 21 among treatments.In conclusion, feeding CLA to Yellow broiler chickens resulted in significantly reduction of fat accumulation, influenced meat quality and enhanced immune function.