ANTIOXIDANT POTENTIAL OF WATERMELON JUICE AND ASCORBIC ACID IN THE MANAGEMENT OF HEAT-INDUCED OXIDATIVE STRESS IN LAYER CHICKENS

Abstract

High ambient temperature (≥30℃) is an important environmental stress factor confronting poultry industry in the tropical regions worldwide. It generates excess reactive oxygen species (ROS) to overwhelm endogenous antioxidant enzymes activities and induces oxidative stress which causes lipid peroxidation and cell damage. This study investigated the potentials of watermelon juice (WJ) and ascorbic acid (AA) in boosting antioxidant enzymes activities against oxidative stress and lipid peroxidation in heat-stressed layer chickens. A total of ninety-six ISA brown layers of 34 weeks old were randomly allotted into four groups each containing 24 birds with three replicates. The control group (C) was given water (non-supplemented), the test groups (T1 and T2) were supplemented with 20 and 40% WJ in water respectively and the reference group (R) was supplemented with 200mg AA/litre of water. Data generated were subjected to one-way ANOVA. Results revealed that supplementation with WJ and AA significantly (p<0.05) boosted activities of superoxide dismutase (C: 0.73U/ml, T1: 3.82U/ml, T2: 10.00U/ml and R: 9.27U/ml), catalase (C: 7.51nmol/min/ml, T1: 11.09nmol/min/ml, T2: 26.70nmol/min/ml and R: 18.20nmol/min/ml) and glutathione peroxidase (C: 6.11nmol/min/ml, T1: 47.88nmol/min/ml, T2: 93.53nmol/min/ml and R: 55.01nmol/min/ml) and significantly decreased malondialdehyde plasma concentrations (C: 0.52μM, T1: 0.33μM, T2: 0.01μM and R: 0.19μM). The effects were generally distinctive at 40% WJ supplementation level. Due to antioxidant effectiveness of WJ and AA recorded in this study. It was concluded that WJ be supplemented in water for combating heat stress in laying chickens.