Effects Of Pu-Erh Tea Pomace On Performance,Meat Quality And Cecal Flora Diversity Of Chahua Chicken No.2

The steady growth in demand for livestock and poultry products has led to a global shortage of feed resources.Therefore,there is an urgent need to develop unconventional feed resources.Pu-erh tea pomace,a solid matter left after the extraction of functional substances,is rich in protein and dietary fibre and can be applied to livestock and poultry production as an unconventional feed resource.However,the application of pu-erh tea pomace in the poultry industry is rarely reported.Chahua Chicken No.2,the 2nd mating line obtained from the selection of chahua chicken generations of inbreeding,has the advantages of higher meat yield and better meat quality.Therefore,in this study,144 Chahua Chickens NO.2 were used as the research object,and the chickens were divided into three groups(CK group,T1 group and T2 group)through a one-way completely randomized design.The CK group,T1 group and T2 group were fed the a basic diet,basic diet with 1.0%pu-erh tea residue and basic diet with 2.0% pu-erh tea residue,respectively.The test period was 28 d.Feed intake and body weight were counted during the test period,and the chickens were slaughtered at the end of the test to determine corpses performance,serum biochemistry,meat quality,fatty acids of cecum contents and 16 S r RNA sequencing,the difference indexes were correlated at the end.The results were as follows:1.Effect of pu-erh tea pomace on production performance and corpose performance of Chahua Chicken NO.2Compared with the CK group,there were no significant differences in final weight,live-weight gain,average feed intake,full net bore weight,half net bore weight,liver weight and abdominal fat weight between the T1 and T2 groups.2.Effect of pu-erh tea pomace on meat quality and muscle amino acid content of Chahua Chicken NO.2Compared with the CK group:(1)No significant changes in muscle shear force,cooking loss,tethering force,p H 45 min and p H 24 h in T1 and T2 groups;(2)The pectoral muscle Cys content was highly significantly lower(P < 0.01)and Thr content was significantly lower(P < 0.05)in the T1 group,and there was no significant change in the content of the remaining 15 amino acids,T＿AA,U＿AA,S＿AA and B＿AA;the pectoral muscle Asp,Thr,Ser,Glu,Ala,Cys,Val,Met,Leu,Tyr,Lys,Arg,Pro,T＿AA and U＿AA contents were highly significantly reduced(P < 0.01),Ile,Phe,His,T＿AA and U＿AA contents were significantly reduced(P < 0.05),and Gly contents did not change significantly;(3)The Tyr content of the leg muscles in the T1 group was highly significantly lower(P < 0.01),and the Asp,Thr,Ser,Glu,Ala,Cys,Val,Ile,Leu,Phe,Lys,Arg,T＿AA,S＿AA and B＿AA contents were significantly lower(P < 0.05),while the Gly,Met,His and U＿AA contents did not change significantly;There was no significant change in the amino acid content of leg muscle in T2 group.3.Effect of pu-erh tea pomace on serum biochemistry of Chahua Chicken NO.2Compared with the CK group,the serum TG,TC and LDL-C contents were significantly lower in the T1 and T2 groups(P < 0.05).4.Effect of pu-erh tea pomace on the content of short-chain fatty acids in the cecum of Chahua Chicken NO.2Compared with the CK group,the content of isobutyric acid and isovaleric acid in the cecum of T1 and T2 groups was significantly increased(P < 0.05),and the content of valeric acid in the T1 group was increased(P < 0.05).5.Effect of pu-erh tea pomace on the diversity of cecum flora of Chahua Chicken NO.2(1)α diversity results: compared with the CK group,there were no significant changes in the sobs index,chao index and ACE index of cecum flora in the T1 and T2 groups,and the shannon index,Simpson index and Pielou index in the T2 group were significantly lower(P < 0.05),while sobs index,Chao index,ace index,Shannon index and Pielou index in T1 group,Simpson index and Pielou index were not significantly changed.(2)PLS-DA results: there was a trend of separation between the cecum flora aggregation interval in the T1 group and the CK group(P=0.07),and the cecum flora aggregation interval in the T2 group was completely separated from the CK group(P< 0.05).(3)Species composition results: at the phylum level,Bacteroidetes and Firmicutes were the dominant flora in the cecum;at the family level,Bacteroidota,Acidaminocaccacese,Rikenellaceae and Lachnospiraceae were the dominant flora in the cecum of Chahua Chicken NO.2;At the genus level,Bacteroides,Rikenllaceae＿RC9＿gut＿group,and Phascolarctobaterium were the dominant groups in the cecum.(4)Differential microbial results: at the family level,the relative abundance of Bacteroidota and Rrevotellaceae in the cecum of the T2 group was significantly higher(P < 0.05),and the relative abundance of Ruminococcaceae was significantly lower(P < 0.05);at the genus level,Bacteroides in the cecum of the T2 group of Chahua Chicken NO.2,Bacteroides,Prevotellaceae＿UCG-001 microbial relative abundance was significantly increased(P < 0.05)and CHKCI001 microbial relative abundance was significantly decreased(P < 0.05)at the genus level.6.Spearman correlation analysis of difference indexes(1)The results showed that serum TG levels were highly significantly negatively correlated with Prevotellaceae＿UCG-001(P < 0.01),significantly positively correlated with CHKCI001(P < 0.05),and LDL-C levels were significantly positively correlated with CHKCI001(P < 0.05);pectoral Asp,Thr,Ser and Arg were significantly correlated with the cecum in the levels of Glu,Ala,Ile,Met,Leu,Tyr,Phe,His and Lys were significantly and negatively correlated with the abundance of Bacteroides in the cecum(P < 0.05),and the levels of His were significantly and positively correlated with the abundance of CHKCI001 in the cecum(P < 0.05);the levels of Asp,Thr,Ser and Arg in the leg muscle were significantly and positively correlated with the abundance of CHKCI001 in the cecum(P < 0.05).muscle Asp,Thr,Ser and Pro content were significantly negatively correlated with Bacteroides abundance in the cecum(P < 0.01),and Glu,Ala,Ile,Leu,Tyr,Phe,His,Lys and Arg content were significantly negatively correlated with Bacteroides abundance in the cecum(P < 0.05).CONCLUSION: Diets fed with 1% and 2% levels of pu-erh tea pomace had no effect on the production performance and slaughter performance of Chahua Chickens NO.2;the addition of 1% and 2% pu-erh tea pomace changed the content of amino acids in muscle and had no effect on muscle quality;the addition of 2% level of pu-erh tea pomace changed the composition and diversity of microorganisms in the cecum and regulated blood lipid metabolism.Pu-erh tea pomace can be applied to broiler breeding industry as a non-conventional feed additive,providing a reference for the application of new feed resources in livestock and poultry,and providing a reference for the development of pu-erh tea pomace as a non-conventional feed resource.