Effects Of Dietary Tea Residue And Microecological On Performance,egg Quality And Blood Biochemical Index Of Laying Hens

With the rapid intensive development of animal husbandry in China,drug additives are widely used in animal feed to promote production,improve the economic benefit,but drug use for a long time,especially the abuse of antibiotics caused such as pathogen resistance,drug residues of animal products and a series of problems,to explore alternatives to antibiotics is very important.In this study,two parallel experiments were designed to study the effects of diets supplemented with different proportions of tea residue and microecological preparations on performance,egg quality,serum biochemical index and antioxidant capacity of laying hens,so as to provide scientific basis for the research and development of green additives for layers.Trial 1: Effect of diets supplemented with different proportions of tea residue on performance,egg quality and blood biochemical index and antioxidant capacity of laying hens.This experiment was conducted to study the effects of dietary different tea residue proportions on performance,egg quality,blood biochemical index and antioxidant capacity of laying hens.Two hundred and forty healthy Roma laying hens with similar body weights of 26-week-old were randomly allotted to 3 treatments with 5 replicates per group and 16 hens per replicate.The laying hens in the control group were fed a basal diet,and those in experimental groups were fed the basal diets supplemented with 1.0%,1.5% tea residue,respectively.The experiment lasted for 42 days.The results showed as follows: 1)Dietary tea residue had an significantly decreased average daily feed intake and the ratio of feed to egg(P<0.05),there were no significant differences on laying rate and average egg weight(P>0.05).2)Adding 1%,1.5% tea residue can increase 21-day the albumen height and egg shape index(P<0.05),and adding 1.5% tea residue significantly improved 21-day the yolk color(P<0.05);Dietary supplementation of 1%,1.5% tea residue can increase 42-day yolk color(P<0.05),significantly reduced yolk cholesterol level(P<0.01),adding 1% tea residue can increase 42-day the egg shape index(P<0.01),while it did not significantly affect egg weight,yolk weight,yolk ratio,yolk index,eggshell strength,eggshell thicknes(P>0.05).3)Adding 1%,1.5% can decrease ALB and GLU contents of serum(P<0.05),and adding1.5% tea residue significantly decerased the serum total cholesterol(TC)in plasma(P<0.05),and significantly increase the activities of total glutathione peroxidase(GPx)of serum(P<0.05).Trial 2: Effect of diets supplemented with different proportions of microecological preparation on performance,egg quality,blood biochemical index and antioxidant capacity of laying hens.The purpose of this experiment was to investigate the effects of different levels of microecological preparation on performance,egg quality,blood biochemical index and antioxidant capacity of laying hens.240 healthy Roman powder shell laying hens of 26 weeks of age with similar weight were selected and randomly divided into three groups according to the requirements of the experiment.Each group was divided into five replicates with 16 hens per replicate.The control group was fed basal diet,and 1.5%,3% of the microecological preparation were added to the basal diet.The experimental period lasted 42 days for the 7 days preliminary trial period.The experiment included two periods: the early period of experiment(0-21 days)and the late period of experiment(21-42 days).The results showed that: 1)Different diet treatments had no significant effects on laying rate and average egg weight during the two periods(P>0.05),while the diets supplemented with 1.5%,3%microecological preparation can improve laying rate in the later period of the experiment(P<0.05),3% microecological preparation significantly reduced the average daily feed intake of laying hens during the two periods(P<0.05),significantly reduced the average daily feed intake and feed-egg ratio of laying hens in the later period of the experiment(P<0.05),and feed-egg ratio of laying hens during the two periods(P<0.01).2)Compared with the control group,the diets added 1.5%,3% microecological preparation had the tendency to improve21-days egg yolk color and shell thickness(0.05<P<0.1);Dietary supplementation of 1.5%,3% microecological preparation significantly reduced 42-days yolk cholesterol level(P<0.01),and 3% microecological preparation significantly increased 42-days shell thickness(P<0.01),there were no significant effect on other conventional egg quality(P>0.05).2)Dietary supplementation of 1.5%,3% microecological preparation significantly increased serum total antioxidant capacity(P<0.05),and 3% microecological preparation significantly decreased serum total cholesterol content(P<0.05).It is concluded that the basal diet supplemented with tea residue could improve feed utilization and egg quality of laying hens,both tea residue supplemental levels above can improve the antioxidant ability of laying hens,The results from this study indicate that 1.5%tea residue is the optimum supplemental level.The addition of microecological preparation in the diet could improve feed utilization,egg quality and the antioxidant capacity of laying hens,and the effect of adding 3% of microecological preparation was better.