The Production Performance, Meat Quality Improvement,And Safety Evaluation Of Eucalyptus Leaf Extract On Pigs

A large number of eucalyptus are used for paper-making and combustion in our country. Some studies have shown that the polyphenols from leaves of eucalyptus have good oxidation resistance.To better study the activity of polyphenols in the leaves of eucalyptus,we take the eucalyptus forests NO.9 leaves as raw material and use different methods to extract polyphenols. We can get the best extraction conditions.We added the polyphenols to the diets of pigs and study the growth performance and the meat of quality improvement, and safety evaluation. The content and results of this thesis are as follows:(1)We take the single factor to extract polyphenols and obtain the optimum extraction conditions. We can get the best conclusion that the best temperature is 25 and the ethanol concentration is 70% and the ratio of solid to liquid is 1:7 and the best time is 2.We can get the best extraction rate of polyphenols is 31.10%.(2)We use the the polyphenols to the pigs feeding. The results showed that the adding amount of 0.03%、0.06%、0.09% and 0.12% of the eucalyptus leaves can reduce the ratio of feed to meat.The adding amount of 0.03%、0.09% of the eucalyptus leaves can reduce the quality of meat. The adding amount of 0.03%、0.06%、0.09% and 0.12% of eucalyptus leaves can increase the content of myoglobin in the meat.The adding amount of 0.03%、 0.06% and 0.09% and 0.12% eucalyptus leaves can significantly improve the fleshy valine concent-ration and concentration of lysine.The adding amount of 0.06%、0.09% and 0.12% of the eucalyptus leaves can increase the concentration of serine fleshy(3) Antioxidant effect. The adding amount of 0.09% eucalyptus leaves can significantly increase the activity of SOD enzyme content (P<0.05), and the adding amount of 0.09% and 0.12% eucalyptus leaves can significantly increase serum GSH-Px enzyme live (P< 0.05). The adding amount of 0.06%、0.09% eucalyptus leaves’ T-AOC (total antioxidant capacity) were all significantly higher than the blank group (P<0.05). It shows that feed add different proportions of eucalyptus leaf extracts can improve the oxidation resistance of feed, and the higher of the amount of the eucalyptus leaves, the higher of the level of dietary antioxidant.(4) We found that the poly-phenol LD50 (LD50) of=5326.9mg/kg (5.32mg/g),which is belong to no poison. We detect the blood of pigs, and found that eucalyptus leaves extracts had no effect on the blood safety index.