Effects of Multi-strain Bacillus Spore Probiotics on Growth, Digestive Function, and Gut Microbiota in Cesarean-Delivered Neonates

Inclusion Criteria: * Healthy term neonates delivered by cesarean section. * Infants were born at term, ranging from 38 to 40 weeks' gestation. * Birth weight appropriate for gestational age (AGA), defined as between the 10th and 90th percentiles for gestational age (≥P10 and ≤P90). * The infant's parent(s) or legal guardian(s) provide written informed consent and agree to comply with study procedures. Exclusion Criteria: For the neonate: * Multiple births (twins, triplets, etc.) * Birth weight outside the appropriate-for-gestational-age range: small for gestational age (SGA, \< P10) or large for gestational age (LGA, \> P90). * Major congenital abnormalities affecting the hematologic, hepatobiliary, cardiovascular, renal/urinary, or gastrointestinal systems; severe inborn errors of metabolism; or suspected primary immunodeficiency. * Prior exposure to systemic or enteral antibiotics (oral, IV, or IM) before the baseline assessment. * Known allergy or intolerance to any component of the investigational product. * Concurrent participation in another interventional clinical trial. * The investigators judge the neonate to be unsuitable for participation. * Parent(s) or legal guardian(s) who do not comply with study requirements or refuse to sign the informed consent. For the mother: * Mother diagnosed with a serious or unstable medical condition involving the hepatobiliary, renal/urinary, cardiovascular, respiratory, endocrine/metabolic, or psychiatric systems. * Mother who intends to use, or is prescribed, any other probiotic/prebiotic product for herself or the infant during the study period.