Effects of dietary polysavone (Alfalfa extract) and chlortetracycline supplementation on antioxidation and meat quality in broiler chickens.

1. A total of 360 1-d-old male commercial Arbor Acre broiler chickens were randomly assigned to 5 groups (6 replicates of 12 birds each) to evaluate the dietary effects of polysavone (0·5, 1·0 and 1·5 g/kg), a natural extract from alfalfa, and 0·15 g/kg chlortetracycline (CTC) on growth performance, antioxidation and meat quality of broiler chickens. 2. Over the 6-week study, feed intake increased significantly with CTC supplementation and final body weight (BW) was significantly higher for 1·0 g/kg polysavone and 0·15 g/kg CTC treatments. Feed:gain ratio was not significantly affected by the dietary treatments. 3. At 3 weeks of age, serum total superoxide dismutase (T-SOD) activity for all polysavone treatments was significantly higher than controls, liver T-SOD activity in 1·5 g/kg polysavone group was significantly higher than the control and CTC groups, and serum glutathione peroxidase (GSHPx) activity for 1·5 g/kg polysavone and liver GSHPx activity in all polysavone groups were significantly higher than CTC. 4. At 6 weeks of age, serum and liver T-SOD activity in 1·5 g/kg polysavone group and liver GSHPx activity for all polysavone treatments were higher significantly than the control and CTC groups, and serum malondialdehyde (MDA) content for all polysavone treatments was significantly lower than CTC. 5. Breast muscle T-SOD activity and pH value at 6 weeks of age were significantly higher and MDA content was significantly lower in 1·0 and 1·5 g/kg polysavone groups than in the control and CTC groups. Breast muscle shear force was significantly lower in l·5 g/kg polysavone group compared with the control, and drip loss for all polysavone treatments was significantly lower than CTC. 6. It was indicated that polysavone modulates antioxidation and modifies meat quality, but with no adverse effect on performance of broiler chickens, and that CTC can be beneficial to performance but has no beneficial effect on antioxidant function or meat quality.