Effects of distillers dried grains with solubles and dietary fiber on the intestinal health of young pigs and chicks

The objective of this research was to determine the value of dietary fiber (DF) from distillers dried grains with solubles (DDGS) on the promotion of intestinal health in young pigs and chicks. Furthermore, purified sources of DF were used in pigs to elucidate whether the soluble or insoluble fraction of DF, or its absence from the diet, is beneficial in the prevention and recovery from post-weaning colibacillosis (PWC). The experimental approach consisted of developing a disease challenge model of PWC in pigs and coccidiosis in chicks. In pigs, a strain of ??-hemolytic F18 Escherichia coli (Ecoli) was selected based on its capability to colonize and cause mild diarrhea. The inoculation consisted of 3 consecutive daily doses of either distilled water (Sham) or 10e10 cfu of Ecoli/dose. Inoculation began on d 3 or 5 after weaning, considered post-inoculation (PI) d 0. In chicks, a dose of Eimeria acervulina (EA) was selected to reduce growth by about 20%. The inoculation consisted of a single dose of either distilled water (Sham) or 10e6 sporulated EA oocysts. Inoculation occurred on d 10 of age. Variables of response included signs of disease such as growth depression and diarrhea; changes in fecal coliforms by culturing; changes in bacterial populations of intestinal mucosa by molecular methods, targeting the V3 region of the bacterial 16S ribosome; and intestinal morphology. In pigs, the inoculation with Ecoli changed the populations of fecal coliforms over time. The pathogenic coliforms gradually replaced the commensal coliforms until PI d 6; then, the commensal coliforms gradually recovered and replaced the pathogenic coliforms (time quadratic, P < 0.001). This pattern of response shows the course of disease from infection to recovery. The inclusion of 10 or 20% DDGS in the diet delayed the drop in commensal coliforms during the infection and hastened the drop in pathogenic coliforms during recovery (diet ?? challenge ?? time, P < 0.01). This effect was observed in 2 consecutive experiments. During recovery from PWC, increasing concentrations of dietary DDGS decreased diarrhea (diet linear, P < 0.01) and increased villus height in jejunum of Ecoli pigs (diet linear ?? challenge, P < 0.001). Also in recovery, pigs fed either 5 or 10% DDGS had a larger bacterial diversity in cecum (P = 0.02) and colon (P = 0.08), than those fed 0 or 20% DDGS. When purified sources of DF were used, pigs fed a diet with insoluble dietary fiber recovered faster (P < 0.05) from PWC diarrhea. In chicks, the inclusion of up to 20% DDGS in the diet did not ameliorate the reduction in performance caused by EA. However, the cecal bacterial diversity and homogeneity within treatments were increased by feeding 10% DDGS (diet quadratic, P < 0.001). Those changes in cecal microbiota can be interpret as beneficial for the intestinal health. In conclusion, DF did not prevent PWC in pigs or coccidiosis in chicks. However, the inclusion of insoluble DF from either DDGS or a purified source in pig diets hastened the recovery from PWC