Effects Of Enterococcus Durans And Different Fermentation Broths On Performance,Serum Biochemical Parameters,Intestinal Morphology And Cecal Microflora In Broilers

As a substitute for antibiotics,bacteriocin is widely used in the feed industry and animal production.It has the effects of inhibiting the growth of pathogenic bacteria,improving animal performance and intestinal health,but due to low yields and large differences in feeding effects.It is hoped to find strains with stable probiotic performance and good feeding effect.This experiment explored the changes in the growth,acid production and bacteriostatic properties of Enterococcus durans under different culture systems in vitro,and studied the differences in the effects of fermentation broth on the growth and metabolism of Enterococcus durans.On this basis,the enduring enterococci cells and fermentation broth were added together for the feeding experiment.200 healthy meat cocks?Ross 308?with a similar body weight were selected and randomly divided into 4 treatment groups:G1 No anti-blank control group),G2?add 1‰chlortetracycline?,G3(add 2×10⁸ CFU·Kg^-1Enterococcus durans and 6%concentrated single bacteria fermentation broth),G4(add 2×10⁸ CFU·Kg^-1 Enterococcus durans and 6%concentrated co-culture fermentation broth),feeding period of 42 days,aiming to investigate the effects of mixed addition of Lactobacillus plantarum and fermentation broth on broiler performance,serum biochemical indicators,small intestine morphology and cecum microbial flora.The main findings are as follows:?1?Under the co-cultivation system with Staphylococcus aureus,the number of viable durable Enterococcus bacteria increased significantly?P<0.05?;the rate of p H decrease increased rapidly,and finally stabilized at 3.67;the bacteriostatic rate of the co-culture fermentation broth against E.coli It is significantly higher than the fermentation broth of single bacteria culture?P<0.05?,and the suitable culture end point is 24h.When co-cultured with durable enterococci and co-culture medium,the viable bacterial counts at 12 and 24 hours in the 6%concentrated fermentation broth treatment group were significantly higher than those in the single bacteria culture control group?P<0.05?,and the bacteriostatic rate was significantly higher than that of single bacteria Culture fermentation broth?P<0.05?.?2?During the first 1-21 days of the experiment,the average daily gains of G3 and G4 were significantly higher than those of G1 and G2?P<0.05?,and the average daily gains of the G4 group were significantly higher than G3?P<0.05?;The daily feed intake was significantly higher than G1 and G2?P<0.05?;the feed-weight ratio of G3 and G4 was significantly lower than that of G1 and G2?P<0.05?.At 21-42days,the average daily gains of all treatment groups were not significantly different?P>0.05?;the average daily feed intake of G4 was significantly higher than that of G1,G2,and G3?P<0.05?;There was no significant difference in weight ratio?P>0.05?.The average daily feed intake of G3 and G4 was significantly higher than that of G1 and G2?P<0.05?during the entire test period 1-42 days??3?G3 and G4 had significantly lower abdominal fat rates than G1 and G2?P<0.05?.?4?The total serum protein content of G3 and G4 was significantly higher than that of G1 and G2?P<0.05?;the blood glucose content of G3 and G4 was also significantly higher than that of G1 and G2,and the blood glucose content of G3 was significantly higher than G4?P<0.05?.?5?G3 and G4 duodenal villi height was significantly higher than G1 and G2?P<0.05?;G3 and G4 crypt depth was significantly lower than G1 and G2?P<0.05?,V/C was significantly higher than G1 and G2.?P<0.05???6?The richness of G4 is relatively high.In terms of phylum richness,the top three microbial phylums of G4 are Thick-walled Phylum,Bacteroidetes and Proteobacteria.The number of G4 thick-walled bacteria was significantly higher than that of G1?P<0.05?.In terms of genus-level richness,Bacteroides G3 was significantly higher than G1?P<0.05?.