Effectsof Macleaya Extractcombined With Bacillus Subtilis On Growth Performance And Intestinalflora Ofchicks

This study used 3×3 two-factor design to investigate the effect of Macleaya Cordata extract and Bacillus Subtilis on the breeding of Xuefeng black bone chicken.To study its effects on the growth performance,serum biochemical indexes and intestinal flora of Xuefeng black bone chicken chicks,so as to provide data basis for screening the appropriate addition amount of the combined use of the two additives,and provide new ideas for healthy breeding in the future.Set three levels for MCE and BS respectively(MCE:0 mg/kg,666 mg/kg and 1332 mg/kg;BS:0 mg/kg,300mg/kg and 600 mg/kg;the mass fraction of sanguinarine in MCE is 0.375%;the number of viable bacteria in Bacillus subtilis is 1×10~9CFU/g)were divided into group I-IX.group I was the blank control group for 42 days.Compared with the blank control group,the results showed that:(1)at the age of 1-21 days,the addition of MCE and 300 mg/kg BS in the diet could significantly increase the body weight(BW),average daily gain(ADG),average daily feed intake(ADFI)and reduce the feed weight ratio(F/G)(P<0.05),but there was no significant interaction between the two at this stage(P>0.05).At22-42 days of age,the addition of 1332 mg/kg MCE and 300 mg/kg BS to the diet could significantly increase BW(P<0.05),and their interaction had a significant effect on BW and ADG(P<0.05).(2)The contents of total antioxidant capacity(T-AOC),superoxide dismutase(SOD)and glutathione peroxidase(GSH-Px)in groupⅡ-Ⅸwere significantly higher than those in group I(P<0.05).The addition of 1332 mg/kg MCE could significantly increase the contents of serum SOD and GSH Px(P<0.05),and the addition of 300 mg/kg BS could significantly increase the content of serum albumin(ALB)and reduce the content of urea nitrogen(BUN)(P<0.05).The interaction between them had a significant effect on the contents of TP and BUN(P<0.05).(3)The addition of MCE in diet could significantly increase the villus height(VH)and villus to crypt ratio(V/C)of jejunum,ileum and duodenum(P<0.05),and significantly reduce the crypt depth(CD)of jejunum and duodenum(P<0.05);Dietary BS could significantly increase jejunal VH and V/C and significantly reduce CD(P<0.05);However,there was no significant interaction between MCE and BS on the morphology of small intestine of 42 day old chicks(P>0.05).(4)The addition of MCE and 300 mg/kg BS in diet could significantly reduce the abundance of harmful bacteria such as Proteobacteria and Desulfovibrio(P<0.05),and significantly increase the abundance of beneficial bacteria such as Rikenella RC9 gut group and Lactobacillus.The combination of the two had significant interaction with Simpson index,Proteus,Rikenellaceae RC9 gut group of physical research bacilli and Lactobacillus(P<0.05).(5)The abundance of Megasphaera was negatively correlated with the content of BUN.The abundance of Rikenellaceae RC9 gut group and unclassified o Bacteroides in intestinal microorganisms was positively correlated with the levels of BW,ADG,ADFI,TP,ALB,T-AOC,SOD and GSH Px,and negatively correlated with the levels of AST and ALT.In conclusion,the addition of MCE,BS alone or both can promote the growth of chicks by improving serum biochemical indexes,antioxidant capacity,promoting the proliferation of beneficial bacteria and inhibiting the growth of harmful bacteria,and improving the morphology of small intestine.However,the combined effect of the two is equivalent to that of single use.The optimum dosage of MCE or BS was1332 mg/kg and 300 mg/kg respectively;The recommended dosage for the combination of the two is 666 mg/kg MCE and 300 mg/kg BS at the age of 1-21days,1332 mg/kg MCE and 300 mg/kg BS at the age of 22-42 days.