Managing the developing gut microbiota of growing piglets - novel probiotic and prebiotic strategies

Keywords: creep feeding, weaning, intestinal microbiota, Lactobacillus sobrius, prebiotics, daidzein, probiotics, 16S rRNA, DGGE, cloning, real-time PCR Nursing is a major critical period in the life of piglets. On one hand maternal antibodies are not able to cross the placenta, thus piglets are born without circulating antibodies and consequently lack maternal passive protection. On the other hand, creep-feeding and weaning increase susceptibility to gut disorders, infections and diarrhea. Therefore clarification of the composition and function of the normal gut microbiota of piglets is pivotal as a knowledge base for the design of innovative nutritional strategies based on pre- and probiotics to keep piglets healthy. The objectives of this study were to describe the composition and function of the intestinal microbiota of piglets during the nursing period through creep feeding and weaning, to in vivo and in vitro evaluate the effect of daidzein on composition and function of intestinal microbiota of nursing piglets in order to evaluate its prebiotic function, and to investigate the probiotic effect of Lactobacillus sobrius S1 on composition and function of intestinal microbiota of nursing piglets. The porcine intestinal microbiota development and diversity, the in vivo and in vitro evaluation of prebiotic effect of daidzein and the investigation of probiotic effect of Lactobacillus sobrius S1 on composition and function of intestinal microbiota of piglets during nursing period through creep feeding and weaning was described using real-time PCR, and PCR analysis of 16S ribosomal RNA gene by denaturing gradient gel electrophoresis (DGGE) and cloning, in combination with analysis of gas production, lactate and VFA yield. The data obtained during the course of the study indicated that 1) Early creep-feeding stabilizes the microbiota of piglets around the weaning period. 2) Lactobacillus communities follow a successional change associated with piglet growth and diet shifting. Creep feeding stabilizes the Lactobacillus community of weaning piglets. Within the Lactobacillus community, some members like L. reuteri and L. amylovorus / L. sobrius might be permanent colonizers, while L. delbruckii, L. acidophilus and L. crispatus are more likely to be transient members of the Lactobacillus communities in the piglet´s GI tract. 3) Both in vitro and in vivo evaluations indicated that daidzein has the potential for use as a prebiotic additive in animal feed. 4) Lactobacillus sobrius S1 has the potential of promoting beneficial bacteria and inhibiting pathogens.