Maternal Gut Microbiota and Metabolomic Signatures Are Potential Indicators of Neonatal Calf Birth Weight: A Preliminary Pilot Study

The gut microbiota plays a crucial role in host homeostasis, influencing digestion, metabolism, and immune regulation. Neonatal birth weight is pivotal for early development and long-term productivity. The study identified distinct maternal gut microbiota and metabolomic profiles associated with neonatal calf birth weight, providing preliminary biomarkers for future microbiota-driven reproductive strategies. A cohort of periparturient Holstein dairy cows was strategically selected to establish two distinct experimental groups based on neonatal birth weight stratification: a high birth weight cohort (WU) and a low birth weight cohort (WF). WU cows exhibited enrichment of Burkholderiaceae_A, Turicibacter, Romboutsia_B, Blautia_A, Barnesiella, Clostridium_T, and Paraclostridium, while WF cows had higher levels of Elusimicrobiota, Ruminiclostridium_E, Campylobacter_B, and Odoribacter. Metabolomic profiling identified 85 differentially abundant metabolites. WU cows showed higher levels of 4-imidazoleacrylic acid, 1,2,3,4-tetrahydroacridin-9-ol, 8S-hydroxy-4Z,6E,10Z-hexadecatrienoic acid, 7-hydroxy methotrexate, sorbitol 6-phosphate, and captopril. WF cows exhibited elevated d-proline, l-hydroxy arginine, alanine betaine, sn-glycerol 3-phosphoethanolamine, and anthranilic acid. Correlation analysis further revealed strong associations between microbial taxa and key metabolic pathways. In the WU group, the genera Romboutsia_B, Paraclostridium, Clostridium_T, Turicibacter, and Blautia_A were positively correlated with metabolites such as neoabietic acid, 4-imidazoleacrylic acid, 8 s-hydroxy-4Z,6E,10Z-hexadecatrienoic acid, n-acetylcytidine, 7-hydroxymethotrexate, and O-succinyl-l-homoserine. Conversely, these genera were negatively correlated with alanine betaine, l-hydroxy arginine, d-proline, anthranilic acid (Vitamin L1), sn-glycerol 3-phosphoethanolamine, and 1-deoxy-1-(methylamino)-d-galactitol. In the WF group, Campylobacter_B was positively correlated with 1-myristoyl-2-hydroxy-sn-glycero-3-phosphoethanolamine, sn-glycerol 3-phosphoethanolamine, and anthranilic acid (Vitamin L1), and negatively correlated with 4-imidazole acrylic acid and 7-hydroxy methotrexate. Additionally, Ruminiclostridium_E and Odoribacter negatively correlated with 7-hydroxy methotrexate and captopril. These findings suggest a coordinated microbiota-metabolite interplay influencing fetal development. Identifying maternal specific microbial taxa and metabolic pathways associated with higher-birth-weight calves offers potential biomarkers and intervention targets for optimizing neonatal growth and perinatal health management in dairy cattle.