| With the rapid development of microecology, people gradually realize that through the regulation of intestinal flora, keep the intestinal microecological balance, to maintain intestinal health, is an important factor in the healthy growth of poultry. In recent years, such Astragalus Polysacharin, Ganoderma lucidum Polysaccharide, Lentinan as green and safe feed additives and immune enhancing agent, and they are widely used in animal feed. Polysaccharides are the main components of Fermentation Concentrate of Ganoderma applanatum(Pers.ex Gray.)Pat.(GAC). The present study was designed to investigate the effects of dietary supplementation with GAC on growth performance, intestinal flora, short chain fatty acids(SCFA) and intestinal pH of broilers. A total of 225 one-day-old Arbor Acres broilers were randomly divided into 5 dietary treatments(15 broilers per pen with 3 pens per treatment): blank group(basal diet), antibiotic group(basal diet supplemented with 5 mg flavomycin/kg diet), and three levels of GAC(basal diet supplemented with 1.57%, 3.15% and 6.29% of GAC). The experiment lasted for 42 d.1. Determination of main component and polysaccharide in GAC, the results revealed that: Moisturer was 32.37%, Crude protein was 4.8%, Ether extract was 1.74%, Crude fiber was 0.52%, Crude ash was 1.87%, Nitrogen free extract was 58.7%, Ca was 3.42%, P was 1.66%, Energy was 4.02 MJ·Kg-1, the content of polysaccharide was 3.18%.2. Through the study of the effects of GAC on growth performance of broilers, the results revealed that: In the whole process of growth of Broilers, GAC could increase the average daily gain, at the same time reducing the feed conversion rat. GAC could promote the production performance of broilers.3. By using Real time Quantitative PCR to study the effects of GAC on intestinal microflora of broilers, the results revealed that: 1)According to the Salmonella 16 S rRNA gene, successfully constructed a real-time PCR detection method of Salmonella. S-F(5′-3′):GTGGCGGACGGGTGAGTAA, S-R(5′-3′):CCGTGTCTCAGTTCCAGTGTG. The total reaction system was 20μl, of which the forward primer and reverse primer(10μmol/L) was 0.4μl respectively, DNA was 1μL, 2X All-in-One Qpcr Mix was 10μL. Reaction conditions of real-time PCR were 95°C/3min, then 95℃/10 s, 61℃/30 s for 40 cycles. The standard curve was Y =-3.322*LOG(X) + 48.89, R2=0.996, Eff. = 100.0%. The template detection limit was 3.36×102 copies/μL, the melting curve was single and the coefficient of variation was 1.45%. 2)On day 21, Salmonella were significantly reduced in the broilers fed GAC than that of the blank group(P<0.05). With the increase of GAC content, Salmonella growth was inhibited. Lactobacillus were significantly increased in the broilers fed with GAC than that of the blank group(P<0.05). These results demonstrate that dietary supplementation with GAC increased gut Lactobacillus counts and inhibited Salmonella growth in the early growth of broilers. 3)On day 42, Salmonella were significantly reduced in the broilers fed with 1.57% and 6.29% GAC than that of the blank group(P<0.05), 6.29% GAC is better. Lactobacillus were significantly increased in the broilers fed with GAC than that of the blank group(P<0.05). These results demonstrate that dietary supplementation with GAC inhibited gut Salmonella growth and increased Lactobacillus counts in growth anaphase of broilers.4. By using plate counting method to study the effects of GAC on intestinal microflora of broilers, the results revealed that: 1)On day 21, Salmonella were significantly reduced in the broilers fed with GAC than that of the blank group(P<0.05). Escherichia coli were significantly reduced fed with 6.29% GAC than that of the blank group(P<0.05). Lactobacillus and Bifidobacterium were significantly increased in the broilers fed with GAC than that of the blank group(P<0.05). 2)On day 42, Salmonella were significantly reduced in the broilers fed with GAC than that of the blank group(P<0.05). Escherichia coli were significantly reduced fed with 3.15% and 6.29% GAC than that of the blank group(P<0.05). Lactobacillus were significantly increased in the broilers fed with GAC than that of the blank group(P<0.05). Bifidobacterium were significantly increased fed with 3.15% and 6.29% GAC than that of the blank group(P<0.05). These results demonstrate that dietary supplementation with GAC increased gut Lactobacillus and Bifidobacterium counts and inhibited Salmonella and Escherichia coli growth in broilers growth. GAC could improve the role of intestinal flora.5. Through the study of the effects of GAC on caecum SCFA concentration of broilers, the results revealed that: 1)On day 21, Acetic acid and propionic acid concentration were significantly increased in the caecum fed with GAC than that of the blank group(P<0.05). Butyric acid concentration were significantly increased fed with 6.29% GAC than that of the blank group(P<0.05). Butyric acid concentration were increased fed with 1.57% and 3.15% GAC than that of the blank group(P>0.05). 2)On day 42, Acetic acid and propionic acid concentration were significantly increased in the caecum fed with 1.57% and 6.29% GAC than that of the blank group(P<0.05). Butyric acid concentration were significantly increased fed with GAC than that of the blank group(P<0.05). These results demonstrate that dietary supplementation with GAC could increase concentration of acetic acid, propionic acid and butyric acid.6. Through the study of the effects of GAC on caecum pH value of broilers, the results revealed that: 1)On day 21, Caecum pH value was significantly reduced in the broilers fed with 6.29% GAC than that of the blank group(P<0.05). Caecum p H value was significantly reduced in the broilers fed with 6.29% GAC than 1.57% and 3.15% GAC group(P<0.05). 2)On day 42, Caecum pH value was reduced fed with GAC than that of the blank group(P>0.05). These results demonstrate that dietary supplementation with GAC could reduced caecum pH value, made the gut in acidic environment and for intestinal health of broilers. |
PDF Full Text Request