Effects of 2'fucosyllactose and Bifidobacterium longum subsp. infantis on the Brain and Cognitive Development in the Young Pig

Abstract Objectives Prebiotics and probiotics have been studied for their beneficial effects on various aspects of development, but much remains unknown regarding interactive effects of their supplementation. This study investigated the effects of dietary 2’fucosyllactose (2’FL; prebiotic) and Bifidobacterium longum subsp. infantis (Bi-26; probiotic) on behavioral and brain structural development in the young pig. Methods Fifty-two intact male pigs were provided ad libitum access to a nutritionally adequate milk replacer without (control) or with 0.532% 2’FL from postnatal day (PND) 2 to 34/35. Pigs were further stratified to receive either glycerol stock alone or Bi-26 (109 CFU) in glycerol stock solution daily. All pigs were subjected to the novel object recognition (NOR) task, a behavioral paradigm assessing recognition memory, from PND 27 to 31. Pigs underwent magnetic resonance imaging procedures at PND 32 or 33 to assess absolute and relative brain volume. Additionally, brain microstructure was quantified using diffusion tensor imaging (DTI) to assess fractional anisotropy, and axial, radial, and mean diffusivity. Results Behavioral outcomes confirmed that there were no effects of prebiotics or probiotics on recognition memory (P > 0.05). Interactive effects (P < 0.05) were observed for the number of object visits, latency to the first object visit, and number of sample object visits. Pigs that received the probiotic supplementation (P < 0.05) spent less time engaging with the sample object in total and on average, were observed to have smaller absolute brain volumes for 9 of 27 total observed regions of interest, and smaller relative volumes for 2 regions associated with kinesthesia. Differences in axial diffusivity were observed in pigs supplemented with the probiotic for 2 of the 12 regions assessed. Interactive effects (P < 0.05) were observed for all DTI outcomes for a variety of brain regions. Trelative volume for the pons was observed to be larger for pigs supplemented with the prebiotic. Conclusions Dietary supplementation of prebiotics and probiotics elicited interactive effects on several exploratory behaviors and structural brain components, and supplementation with probiotics appeared to reduce the volume of specific brain regions. Funding Sources DuPont Nutrition & Biosciences.