Performance and carcass characteristics of broilers fed diets containing cashew nut meal treated or not with antioxidant

This experiment was conducted to evaluate the oxidative stability of cashew nut meal (CNM) treated or not with butylated hydroxytoluene (BHT) at different storage times and the effect of diets containing this ingredient on the performance and carcass characteristics of broilers. A batch of 400 kg of freshly produced CNM was divided into five equal portions. One portion was stored with no antioxidant and the others were treated with 500 ppm of BHT at days zero, 7, 14 and 21. The oxidative stability of CNM was measured by the acidity index and peroxide index determined by weekly samplings of the CNM. At the end of the 35-day storage time, 15% of CNM treated or not with BHT was used in the formulation of broiler diets. A feed trial was carried out with 480 day-old male Ross chicks. Birds were randomly distributed among the 5 treatments with 8 replications of 12 birds each. Acidity index of CNM did not vary, regardless of antioxidant use. However, PI values for CNM with or without BHT increased with storage time. Treatments did not affect broiler performance (feed intake, weight gain and feed conversion), carcass characteristics (carcass yield, breast yield and percentage of liver and abdominal fat), liver moisture, ether extract and abdominal fat moisture content. The ether extract content of the liver, nevertheless, was lower in birds that received diet containing CNM treated with BHT at day zero of storage than those from the control treatment. CNM stored for 35 days without BHT suffered a lipid peroxidation process. However, the use of 15% of this ingredient in diets did not affect broiler performance and carcass characteristics.