Early colonisation and temporal dynamics of the gut microbial ecosystem in Standardbred foals.
Authors: Quercia S, Freccero F, Castagnetti C, Soverini M, Turroni S, Biagi E, Rampelli S, Lanci A, Mariella J, Chinellato E, Brigidi P, Candela M
Journal: Equine veterinary journal
Summary
# Early Colonisation and Temporal Dynamics of the Gut Microbial Ecosystem in Standardbred Foals Understanding how foals establish their essential gut microbiota has received surprisingly little molecular attention, despite the critical role of microbial communities in equine energy metabolism and long-term health. Quercia and colleagues conducted a longitudinal study of 13 Standardbred mare-foal pairs, sampling amniotic fluid, colostrum, faeces and meconium at delivery, then tracking milk and faecal samples from both mares and foals through day 10 post-partum using 16S rRNA gene sequencing. The researchers discovered that microbial colonisation begins *in utero*—founder species from the mare's own gut and milk microbiota establish in foal meconium before birth, with external transmission routes accelerating dramatically after parturition to shape the rapidly assembling neonatal microbiome. For practitioners, these findings underscore that mare microbiome quality during late pregnancy and early lactation directly influences foal gut ecosystem development, suggesting that nutritional, probiotic or management interventions targeting the pregnant and nursing mare warrant investigation as strategies to optimise foal health trajectories. Whilst the study's reliance on 16S sequencing prevents definitive species-level identification and cannot distinguish viable from dead cells, it fundamentally reframes perinatal foal nutrition as a maternal–neonatal microbial transmission event rather than de novo colonisation.
Read the full abstract on PubMed
Practical Takeaways
- •Mare health and microbiota composition directly influence foal microbiome development from fetal life onwards; optimising mare nutrition and management during pregnancy and early lactation may support foal gut health
- •Early separation of mare and foal, or interventions disrupting natural milk transfer and contact, could negatively impact critical microbiome seeding; handle perinatal management cautiously
- •Monitor mare digestive health and colostrum quality as these are primary vectors for beneficial microbial inoculation into newborn foals
Key Findings
- •Microbial components from mare symbiont communities establish in foal gut during fetal life via intrauterine transmission
- •After birth, external transmission of mare microorganisms occurs through milk and faecal contact, creating rapid dynamic assembly of mature foal microbiome
- •Founder microbial species in foal gut are derived from both mare milk and mare gut ecosystems
- •Mare microbiomes are a key factor determining establishment of foal gut microbial ecosystem