Effects of alpha-lipoic acid supplementation on growth performance, antioxidant capacity and biochemical parameters for ammonia-exposed broilers.

In order to estimate the effect of alpha-lipoic acid (LA) supplementation on relieving ammonia stress of broilers, 180 22-day-old male broilers were assigned to three groups, six replicates in each group and 10 birds per replicate. The three groups were: (1) a control group without ammonia stress; (2) exposure to 70 ppm atmospheric ammonia (AM); (3) exposure to 70 ppm atmospheric ammonia and administration of 300 mg/kg LA (AM + LA). The experimental period was 3 weeks. Results showed that average daily weight gain was increased and feed conversion ratio was decreased in the AM + LA group, compared with the AM group (P < 0.05). Total superoxide dismutase and glutathione peroxidase activities in serum, and glutathione content in liver were higher in the AM + LA group than that in the AM group (P < 0.05); however, serum malondialdehyde content was decreased by LA addition (P < 0.05). Additionally, serum glutamic-pyruvic transaminase, creatine kinase and lactate dehydrogenase activities were reduced and albumin level was increased by LA addition (P < 0.05). In conclusion, LA addition could relieve ammonia stress to restore broiler production performance to normal levels.