核桃青皮提取物替代饲用抗生素对黄羽肉鸡生产性能、抗氧化性能的影响

Effects of Extracts from Walnut Green Husk Substituting Feed Antibiotics on Growth Performance and Antioxidant Performance of Yellow Feather Broilers

本试验旨在探究以核桃青皮提取物替代饲用抗生素对黄羽肉鸡生产性能、抗氧化性能的影响。以90%乙醇提取核桃青皮获得提取物,并测定其总酚、总黄酮和多糖含量;根据1,1-二苯基-2-三硝基苯肼(DPPH)自由基清除率和还原能力评价其抗氧化能力;以大肠杆菌(Escherichia coli)、金黄色葡萄球菌(Staphylococcus aureus)和鸡白痢沙门氏菌(Salmonella pullorum)为受试菌,测定抑菌圈直径评价其抑菌活性。选用1日龄雄性黄羽肉鸡192只,依据体重随机分成4组,每组8个重复,每个重复6只鸡,地面育雏至10日龄后采用3层笼养。抗生素组饲喂基础饲粮+10 mg/kg吉他霉素+5 mg/kg黄霉素,试验Ⅰ组饲喂基础饲粮+200 mg/kg核桃青皮提取物,试验Ⅱ组饲喂基础饲粮+500 mg/kg核桃青皮提取物,试验Ⅲ组饲喂基础饲粮+1000 mg/kg核桃青皮提取物。饲养试验期间于21日龄和42日龄记录体重和采食量。在21日龄、42日龄时每个重复选取1只进行屠宰,采集血液,分离肝脏用于血浆、肝脏抗氧化性能测定。结果表明,核桃青皮90%乙醇提取物干物质中总酚、黄酮和多糖含量分别为84.75、208.96和473.86 mg/g;核桃青皮提取物还原能力显著高于90%乙醇;DPPH自由基清除率显著高于维生素E(P<0.01)。核桃青皮提取物对鸡白痢沙门氏菌、大肠杆菌和金黄色葡萄球菌均有一定抑菌作用,其中对鸡白痢沙门氏菌的抑制作用最强。动物试验表明,添加核桃青皮提取物对黄羽肉鸡的体重和采食量均无显著影响(P>0.05);与试验Ⅲ组相比,添加200和500 mg/kg核桃青皮提取物可显著降低1~21日龄的料重比(P<0.05)。添加核桃青皮提取物对21日龄各组间血浆过氧化氢酶(CAT)、超氧化物歧化酶(SOD)及总抗氧化能力(T-AOC)无显著差异(P>0.05),其中试验Ⅰ组血浆丙二醛(MDA)含量相对于抗生素组降低20.90%(P<0.05);与试验Ⅱ组相比,试验Ⅰ组、试验Ⅲ组血浆中谷胱甘肽还原酶(GR)含量分别升高78.86%、107.66%(P<0.01);42日龄时各处理组间血浆MDA、CAT、GR、SOD及T-AOC均无显著差异(P>0.05);添加核桃青皮提取物对21日龄黄羽肉鸡各处理组间肝脏MDA、GR、CAT、T-AOC及SOD均无显著差异(P>0.05);42日龄黄羽肉鸡各处理组间肝脏CAT、T-AOC及SOD均无显著差异(P>0.05),试验Ⅲ组肝脏MDA含量相对于试验Ⅱ组降低36.36%(P<0.01)。试验Ⅱ组肝脏中GR含量相对于试验Ⅲ组升高45.09%(P<0.05)。试验结果表明,以90%乙醇为溶剂获得的核桃青皮提取物含丰富的黄酮、总酚、多糖,在体外具体良好的抑菌活性及抗氧化作用,其中对鸡白痢沙门氏菌的抑制作用强于大肠杆菌及金黄色葡萄球菌。在饲粮中添加200 mg/kg核桃青皮提取物可起到饲用抗生素的作用。

This experiment was conducted to study the effects of walnut green husk(WGH)extracts substituting feed antibiotics on growth and antioxidant performance of yellow feather broilers.WGH extracts were obtained with 90%ethanol,and the contents of total phenol,flavonoids and polysaccharides in WGH extracts were determined.The antioxidant capacity of WGH extracts was evaluated by the reducing power and 1,1-diphenyl-2-picrylhydrazyl(DPPH)free radical scavenging rate.The antibacterial activity against Escherichia coli,Staphylococcus aureus and Salmonella pullorum was also evaluated according to the inhibition zones.A total of 192 one-day-old male yellow-feathered broilers were randomly divided into four groups,and there were 8 replicates per group and 6 birds per replicate.The antibiotic group was fed with basic diet supplemented with 10 mg/kg guitarmycin and 5 mg/kg flavomycin.Test groupⅠwas fed with basal diet supplemented with 200 mg/kg WGH extracts,test groupⅡwas fed with basal diet supplemented with 500 mg/kg WGH extracts,and test groupⅢwere fed with basal diet supplemented with 1000 mg/kg WGH extracts.During the feeding test,feed intake(FI)and body weight(BW)was recorded at 21 and 42 days of age.At 21 and 42 days of age,one bird of each replicate was euthanized,blood and liver were collected,plasma and liver antioxidant properties were measured.The results showed that the contents of total phenols,flavonoids and polysaccharides in dry matter of WGH extracts with 90%ethanol were 84.75,208.96 and 473.86 mg/g respectively;Reducing power and DPPH free radical scavenging rate of WGH extracts were significantly higher than those of 90%ethanol and vitamin E,respectively(P<0.01).According to the inhibition zones,the WGH extracts had bacteriostatic effects against S.pullorum,E.coli,and S.aureus,among which the strongest inhibitory effect was on S.pullorum.Animal feeding experiments showed that the BW and FI were not significantly influenced by WGH extract supplementation(P>0.05).Compared with test groupⅢ,addition of 200 and 500 mg/kg WGH extracts significantly reduced the F/G of 1 to 21 days of age(P<0.05).There was no significant difference of CAT,SOD and T-AOC in plasma between the groups of 21-day-old with the addition of WGH extracts(P>0.05),the plasma MDA content in test groupⅠwas decreased by 20.90%than the antibiotic group(P<0.05);Compared with test groupⅡ,the GR contents in plasma of test groupⅠand test groupⅢwere increased by 78.86%and 107.66%(P<0.01);There were no significant differences of MDA,CAT,GR,SOD and T-AOC in plasma among the four groups at 42-day-old(P>0.05).There were no significant differences of MDA,CAT,GR,SOD and T-AOC at 21-day-old,and CAT,SOD and T-AOC in liver among the four groups at 42-day-old(P>0.05).Compared with test groupⅡ,the liver MDA content in the test groupⅢdecreased by 36.36%(P<0.01),and the GR content in liver of test groupⅡwas increased by 45.09%than that of test groupⅢ(P<0.05).The experiment results showed that WGH extracts obtained with 90%ethanol was rich in flavonoids,total phenols and polysaccharides and have good antioxidant capacity and bacteriostatic effect against pathogenic bacteria in vitro,and the inhibition effects against S.pullorum was stronger than that on E.coli and S.aureus.Adding 200 mg/kg walnut green husk extracts to the diet can achieve the effect of feed antibiotics.