Evaluation of antioxidant properties of Oxalis corniculata L. leaves powder and comparison of its addition effect with vitamin C on performance and meat quality of broilers under heat stress conditions

To investigate the antioxidant properties of Oxalis corniculata L. leaves powder and compare the effects of its addition with vitamin C on the performance and meat quality of broilers under heat stress conditions, an experiment was conducted in a completely randomized design with four treatments, five replications, and 10 birds per replication. The experimental treatments included the corn-soybean diet as a basal diet (control), basal diet + 250 mg kg-1 vitamin C, basal diet + 0.5% O. corniculata leaves powder, and basal diet + 1% O. corniculata leaves powder. To apply heat stress, the chickens from 25 to 42 days of their age were exposed to 34 ± 2 °C for eight hours a day. The performance traits including feed intake, weight gain, and feed conversion ratio were recorded at the end of the experiment. Also, at the end of the experiment, two birds per replicates were randomly selected and slaughtered to measure the meat quality traits. The total phenolic compounds content in the methanolic extract of O. corniculata was 11.73 mg of gallic acid / g of dry matter. The free radical scavenging activity (DPPH assay) percentage and the amount of vitamin C of this plant were obtained 46.63% and 88 mg/g of dry matter, respectively. The consumption of 1% leaves powder of the plant increased the feed intake and weight of broilers compared to the control (p < <0.05). The lowest feed conversion ratio was observed in the group of 1% leaves powder of the plant and vitamin C (p < <0.05). The highest water holding capacity and meat moisture was observed in the broilers fed with O. corniculata leaves powder compared to the control (p < <0.05). All the treatments reduced the cooking loss and dripping loss of meat compared to the control (p < <0.05). According to the results of this experiment, the basal diet + 250 mg kg-1 vitamin C and basal diet + 1% O. corniculata leaves powder treatments could improve the growth performance and some meat quality parameters of broilers under heat stress conditions.