Effects Of Scutellaria Baicalensis And Lactic Acid Bacteria On Growth Performance And Microflora In Ileum And Caecum Of Broilers

Lactic acid bacterial strains (LAB) and baicalin were fed to broilers as feed additives in my experiment to study the probiotic effects of baicalin and LAB to broilers and to further elaborate the mechanism of the interaction between herbal and probiotics in the intestine. At the end of the experiment, the effects of both LAB and baicalin on growth performance of broilers and their microflora in ileum and caecum were studied; the interaction between baicalin and intestinal microflora were further explored. The whole experiment was divided into four sections as follows.In the first section, the experiment was conducted to study the effects of Scutellaria baicalensis and LAB on growth performance of broilers. Nine hundred broilers at the age of 1d were selected and divided into nine treatments with 5 replicates of 20 broilers in each treatment. Five treatments were supplemented with 0 (Control),0.1%,0.2% and 0.4% Scutellaria baicalensis and 1.0% antibiotics (Positive control) in the basal diets respectively; treatment A was fed basal diets supplementing with LAB; treatment B, C and D were fed basal diets supplementing with LAB and Scutellaria baicalensis at levels of 0.1%,0.2% or 0.4% respectively. The experiment lasted for six weeks. The effects of Scutellaria baicalensis on daily gain, feed/gain, immune organ index and the number of LAB and Enterobacter in ileum and caecum of broilers during 1-21d,22-42d, 1-42d were studied. The results showed that supplemental Scutellaria baicalensis of 0.2% could improve growth performance during 1-21d, and better promotion of the role of Scutellaria baicalensis of 0.2% and LAB. But this effect was not obviously during 22-42d and 1-42d.In the second section, the experiment was conducted to study the effects of Scutellaria baicalensis on microflora in ileum and caecum of broilers. Five hundred broilers at the age of 1 d were selected and divided into five treatments with 5 replicates of 20 broilers in each treatment. Five treatments were supplemented with 0 (Control),0.1%,0.2% and 0.4% Scutellaria baicalensis and 1.0% antibiotics (Positive control) in the basal diets respectively. The experiment lasted for six weeks. We would randomly select three broilers from each group on 21d and 42d, slaughtering and sterile collection chymus from ileum and caecum of broilers. The number of LAB and Enterobacter in ileum and caecum of broilers were studied. The results showed that supplemental Scutellaria baicalensis of 0.2% could increase the number of LAB and reduce Enterobacter on 21d. But positive control could reduce the number of LAB and Enterobacter significantly (P<0.05). Positive control could reduce the number of LAB and Enterobacter significantly on 42d (P<0.05), and there was no significantly compared with other groups (P>0.05).In the third section, the experiment was conducted to study the effects of baicalin on LAB in ileum and caecum of broilers. Baicalin of three concentrations (200μg·mL-1,400μg·mL-1 and 800μg·mL-1) were selected as a substrate, LAB of ileum and cecal flora as inoculum. Each treatment has 3 replicates. The pH of ileum after substrate fermentation, LAB counts, the concentration of lactic acid and pH and VFA after fermentation of caecal flora as substrate were determined. The results showed that, compared with control group, different concentrations of baicalin can reduce pH after fermentation of LAB as inoculum in ileum, and increase the number of LAB and improve the concentration of lactic acid, but there was no significant difference (P>0.05). Different concentrations of baicalin can reduce pH after fermentation of cecal flora as inoculum, increase significantly the total production of VFA (P<0.05), and reduce ethylene-propylene to some extent. TreatmentⅢhas the largest decrease in all treatment treatments.In the fourth section, the experiment was conducted to study the degradation of ileum and cecal flora to baicalin. A HPLC method for the quantification of baicalin and baicalein in fermentation broth was established. Baicalin (800μg·mL-1) were selected as a substrate, ileum and cecal flora were selected as an inoculum,72h in vitro fermentation. The results showed that, the concentration of baicalin and baicalein has almost no change in ileal microflora in fermentation broth. But the baicalin content was decreasing in cecal microflora in fermentation broth during Oh to 36h, and the baicalein content was increasing. Both of them were decreased after 36h.