Effects of Armillariella tabescens mycelia on the growth performance and intestinal immune response and microflora of early-weaned pigs.

This study was performed to evaluate effects of Armillariella tabescens (A. tabescens) on the growth performance and intestinal immune response and microflora in early-weaned pigs when used as feed additive. A. tabescens mycelia were added to basal diets at concentrations of 0%, 0.1%, 0.3% or 0.9% (w/w). A total of 144 commercial cross-bred piglets were randomly allocated to one of these four diets and fed for 30 days. The growth performance of early-weaned piglets displayed improvement with diets containing 0.1% and 0.3% dried mycelia powder from A. tabescens. Supplementing with 0.1% or 0.3% A. tabescens mycelia induced a 2.6- and three-fold increase in secretory immunoglobulin A (sIgA) content in the jejunal mucosa, respectively, but had only a marginal effect on sIgA in the ileal mucosa. Expression of interleukin-2, interferon-γ, and tumor necrosis factor-α in the jejunal mucosa were elevated with A. tabescens mycelia administration. Increased amounts of Lactobacillus spp. and Bifidobacterium spp. in the jejunum, and decreased amounts of Escherichia coli in the jejunum and ileum were observed with the administration of A. tabescens-containing diets. This study demonstrated that A. tabescens had beneficial effects on the growth performance and intestinal microflora of early-weaned pigs.

[Study on breeding of probiotic Aspergillus nigre by N+ implantation and fermentation condition of its mutant].

Using Aspergillus niger AN01 as original strain, mutated strain Aspergillus niger AN03 was obtained by N+ implantation. The results showed that activities of acidic protease, cellulase and pectinase of Aspergillus niger were raised from 71.6U/g, 141.7U/g and 264.8U/g to 996.5U/g, 940.4U/g and 906.5U/g respectively. Characteristics of enzymes production in the mutant Aspergillus niger AN03 kept stabile by 5 times subculture. In addition, the optimum conditions for enzymes production of Aspergillus niger AN03 were investigated. The optimum components of medium consisted of bran 105.0g, corn straw 105.0g, bean cake 105.0g, NH4Cl 6.0g, H2O 1000mL. The optimum fermentation condition was incubated for 4d in the condition of pH 5.0 and temperature 30 degrees C.