R. Bras. Zootec.01/Mar/2016;45(3):113-20.
Growth performance, intestinal morphology, and meat quality in relation to alpha-lipoic acid associated with vitamin C and E in broiler chickens under tropical conditions
This study was conducted to examine the effect of alpha-lipoic acid with vitamin C and E on growth performance, intestinal morphology, and meat quality in broiler chickens under tropical conditions. A total of 288 one-day-old male ROSS 308 chicks (40±0.1 g) were used in a completely randomized design and allotted to one of six dietary treatments to form sixe replicates per treatment (eight birds per cage). The six dietary treatments were: a corn-soybean meal-based diet (NC; no antimicrobial compounds added) with 8 ppm alpha-lipoic acid (ALA); 150 ppm vitamin C and 75 ppm vitamin E (E-75); E-75 plus ALA (E-75-ALA); 150 ppm vitamin C and 50 ppm vitamin E (E-50) plus ALA (E-50-ALA); and 150 ppm vitamin C and 25 ppm vitamin E (E-25) plus ALA (E-25-ALA). All dietary treatments were continuously provided in liquid form, dissolved in water. Birds were housed in a battery cage (n = 36), and were offered dietary treatments on an ad libitum basis. The ambient temperature was maintained at 32±1 ºC for the first three weeks and reduced gradually to 28 ºC by the end of the experiment (day 35) to induce moderate tropical condition. One bird per pen (n = 6), and another bird per pen (n = 6) were euthanized via cervical dislocation to obtain terminal ileum to measure villus height and crypt depth at day 21, and to harvest breast meat and drumsticks to evaluate meat quality traits at day 35, respectively. Dietary treatment E-75-ALA improved body weight and average daily gain compared with birds fed other dietary treatments from day 1 to day 35. Birds fed dietary treatment E-75-ALA and E-50-ALA had higher villus height than those fed the other dietary treatments at day 21. Dietary treatments E-75-ALA and E-50-ALA reduced thiobarbituric acid reactive substance (TBARS) in drumsticks compared with other dietary treatments, but only treatment E-75-ALA decreased TBARS in breast meat at day 35. Liquid form of antioxidant compounds such as E-75-ALA can improve growth performance, histology of terminal ileum, and meat quality traits in broiler chickens under moderate tropical condition for 35 days.