The effects of feeding oxidized and refined soy oils with various adsorbents on broiler’s immune response, meat oxidative stability, antioxidant capacity and liver’s enzymes

This experiment was conducted to investigate the possibility of using refined oil with various adsorbents in broiler chicken feed and its effect on immune response, meat oxidative stability, antioxidant capacity and liver’s enzymes. Soybean oil was heated at 180℃ for 20 hours. Then the adsorbents were added to it and the quality of the oil was evaluated. Heating increased (P<0.05) peroxide and carbonyl values in the heated oil. Treatment of burned oil with different adsorbents improved oil quality and the use of α-tocopherol and simultaneous combination of 3 adsorbents had the highest efficiency in reduction of peroxide and carbonyl values (P<0.05). Then, the possibility of using refined oil as an alternative to soybean crude oil in 480 broiler chicks of the commercial strain of Ross 308 was investigated in 8 treatments, 5 replications, and 12 chicks per replicate. Dietary treatments were as: T1: Control (contained 3% crude oil), T2: 3% Crude oil+200 ppm α-tocopherol, T3: 3% oxidized oil, T4: oxidized oil+200 ppm α-tocopherol, T5: refined oil using calcium silicate, T6: refined oil using zeolite, T7: refined oil using rice hull ash, T8: refined oil using a mixture of calcium silicate, zeolite, and rice hull ash. The results showed that feeding burned oil to the broilers, negatively influenced immune response and liver and plasma antioxidant capacity and increased MDA content of thigh and liver’s enzymes(P<0.05). α-tocopherol, calcium silicate and a mixture of 3 mineral adsorbents could compensate for some negative effects of burned oil better than zeolite and rice hull ash(P<0.05).The results showed that supplementing burnt oil with alpha-tocopherol or oil purification with mineral absorbents reduced peroxide content and carbonyl content to an acceptable level and partially compensated for the negative effects of burnt oil in broilers. The composition of calcium silicate can be used for the efficient purification of oxidized oil due to its greater impact on the quality components of oil and the growth indicators of broiler chickens.