Effects Of Jade Screen Powder On Antioxidant Index In Serum, Digestive Enzyme Activities And Performance Of Fattening Bullocks

36 forty months (Limousin cattle X Luxi cattle) fattening bullocks which were healthy and had similar weight, were divided into four groups randomly (a control group and three tested groups). The four treatments were added with jade screen powder (0%, 1%, 1.5%, 2% per concentrate cattle feed). The whole catties were weighed and the blood samples were taken one time per 20 days after jade screen powder administration. In addition, the highest ambient temperature should be recorded everyday. The 36 fattening bullocks were all slaughtered after 60 days of feeding experiment. The objective of the experiment was conducted to study the effects of jade screen powder on performances and mechanism of fattening bullocks by the determination of performances, serum antioxidant activities, digestive enzymes activities in different parts of the alimentary canal.The results demonstrated that the addition of jade screen powder can improve the activities of serum total antioxidative capacity (T-AOC), glutathione peroxidase (GSH-PX), superoxide dismutase (SOD), catalase (CAT) significantly (PO.05). Jade screen powder can decrease the content of malondialdehyde (MDA) and prevent the oxidative stress induced by high ambient temperature. The activities of CAT, SOD, GSH-Px, T-AOC were positively correlated with each other (P<0.01), and they were all negatively correlated with the content of MDA.The addition of jade screen powder can improve the activities of celluase in rumen and pepsin in abomasums significantly (P<0.05). The activities of digestive enzyme varied in different parts of small intestine, were higher in the front than in the lower parts. The activities of digestive enzyme in duodenum were higher than that of other small intestine, and the activities of digestive enzyme in jejunum were higher than that in ileum. Our experiments also indicated that jade screen powder could improve the activities of digestive enzyme in small intestine obviously (P<0.05).The addition of jade screen powder could improve the ADG and F:G, but it had no effect on ADFI. The addition of jade screen powder could improve the slaughter traits of fattening bullocks. It could also promote the deposition of fat in the beef body. F:G was significant correlations with many carcass traits, and was negatively correlated with carcass weight, slaughter rate significantly (P<0.05), so we can evaluate many carcass traits by F:G.