Effects Of Clostridium Butyricum Compound Inoculum On Layer Performance And Egg Quality

In recent years,with the promulgation of the national policy of prohibiting of antibiotics,it is necessary to find green and safe new antibiotic substitutes for antibiotincs.Clostridium Butyricum is a kind of Gram-positive anaerobic Bacillus,which is resistant to gastric acid and bile salt,improving the intestinal microecological balance and enhancing immune function.in 2013,it was included in the“Feed Additives Varieties Catalogue".It is a new type of probiotics with great potential to replace antibiotics.In order to prolong the laying period and improve the economic benefit,The effects of Clostridium butyricum Compound agent(Clostridium butyricum and its metabolites are compounded with other probiotics)on the performance and egg quality of Jingbai No.1 laying hens were achieved.In this experiment,A total of 900Jingbai No.1 laying hens(aged of 48 weeks)weredivided into 3 groups with 3 replicates per group and 100 hens per replicates.The control group was fed a basal diet,and the experimental geoups were fed the basal diet supplemented with 200mg/kg and 400mg/kg Clostridium butyricum compound agent,respectively.The preliminary test lasted for 7 days and the experiment lasted for 45 days.The main testing indicators were production performance(laying rate,mortality rate,etc.),nutritional indicators(amino acids,trace elements,etc.)and bacterial community composition.The main results are as follows:(1)Production performance:The laying rate and average egg weight of the experimental group were higher than those of the control group.Compared with the control group,the laying rate of the experimental group with the addition of Clostridium butyricum compound agent was increased by 2.99%and 1.87%,2.19%and 1.64%in the 4th and 6th weeks respectively(P<0.05),The average egg weight increase by0.99%and 1.51%,2.17%and 1.75%,2.19%and 2.28%in the second,fourth and fifth weeks respectively(P<0.05).There was no significant difference in layingrate and average egg weight between the experimental groups.During 1 to 6 weeks of the experiment,the feed-to-egg ratio and the death rate of the experimental group were lower than those of the control group.Compared with the control group,the death rate of laying hens in Clostridium Butyricum treatment groupwas reduced by 55.07%and41.85%respectively(P<0.05).There was no significant difference in the mortality rate between the experimental groups.When the suppelmental level of Clostridium Butyricum compound agent was 200mg/kg,the production performance of laying hens was the best.(2)Nutritional indicators:the content of vitamin A,vitamin B₂and lecithin in eggs of the experimental groups were compared with those of control group(P<0.05).Test results of the content of amino acids in eggs:Among the essential amino acids,the contents of threonine,valine,leucine and phenylalanine in eggs of the experimental group were higher than those of the control group(P<0.05).Among non-essential amino acids,the contents of alanine,tyrosine,aspartic acid and glutamic acid in eggs of of experimental groups were higher than those of control group(P<0.05).Fatty acid content in eggs:Compared with the control group,the contents of C18:2n6c and C18:3n3 in the Clostridium Butyricum treatment group increased by 28.03%and29.60%,26.02%and 21.80%,respectively.The test results of trace elements in eggs showed that compared with the control group,the content of calcium and magnesium in eggs of experimental group were increased by 5.24%and 5.42%,23.48%and14.78%respectively(P<0.05).(3)Bacterial community composition:the bacterial community in feces was analyzed by high-throughput sequencing technology.Firmicutes was the dominant phylum of the 10 categories with relative abundance more than 0.1%at the phylum level,The content of Firmicutes in Clostridium Butyricum treatment group was all above 77%.At the genus level,Lactobacillus was the dominant genus.Compared with the control group(7.56%,6.37%),the content of Lactobacillus in the experimental group(10.23%,42.38%)increased.