Impact of Colostrum Oropharyngeal Immunotherapy on Postnatal Growth in Preterm Infants

The goal of this clinical trial is to ascertain whether oropharyngeal administration of colostrum contributes to postnatal growth in very preterm infants (those born before 32 weeks of gestation). The main questions it aims to answer are: Can Oropharyngeal administration of colostrum effectively lower the incidence rate of extrauterine growth restriction (EUGR) in participants? Does oropharyngeal colostrum intervention bring about changes in the early gut microbiota of participants? Researchers will conduct a comparative analysis between colostrum and a placebo (normal saline) to investigate whether oropharyngeal administration of colostrum has a beneficial effect on the postnatal growth of participants. Participants will: Initiation of oropharyngeal colostrum administration will take place within 48 - 72 hours after birth, and the treatment will be administered continuously for a period of 5 days. Stool samples will be collected from the participants both before and after the intervention. Participants will be required to maintain a diary to document their basic characteristics and clinical outcomes.