Colonisation of Newborn Piglets with a Mixture of Bacteroides Species Improves Their Gut Health and Performance

Due to the low populations of <i>Bacteroides</i> sp. in the gut microbiota of sows compared to nursed piglets, sows may not represent an ideal source of <i>Bacteroides</i> sp. for newborn piglets. In this study, we therefore tested the effect of oral administration of a mixture of <i>Bacteroides thetaiotaomicron</i>, <i>Bacteroides vulgatus</i>, <i>Bacteroides fragilis</i> and <i>Bacteroides xylanisolvens</i> on the microbiota development of newborn piglets. Oral administration of such a mixture to piglets within 12 h after parturition did not result in any adverse effects. Sequencing of 16S rRNA showed that 4 days after administration, these species formed approx. 20% of total faecal microbiota and affected the development of gut microbiota in treated piglets. The treatment resulted in an increased abundance of <i>Veillonella caviae</i>, <i>Fusobacterium gastrosuis</i>, <i>Dialister</i> sp., <i>Clostridium jeddahitimonense</i>, <i>C. cadaveris</i>, <i>Butyricicoccus pullicaecorum</i>, <i>Actinobacillus indolicus</i>, <i>A. minor</i>, <i>Streptococcus pasteurianus</i>, <i>S. parasuis</i>, <i>S. equinus</i>, <i>S. pluranimalium</i>, <i>S. thoraltensis</i> and <i>S. suis</i>. On the other hand, administration of the <i>Bacteroides</i> mixture suppressed piglet colonisation by <i>C. disporicum</i> and multiple species from family Prevotellaceae. <i>Bacteroides</i>-treated piglets exhibited significantly higher body weight than untreated controls at 3 months of age. Administration of a mixture of <i>Bacteroides</i> shaped the development of gut microbiota in nursed piglets, which resulted in improved parameters at the end of the pre-fattening period.