Improved Respiratory Infection by Consuming Lactoferrin Fortified a2 Growing up Formula in Children of 2 to 3 Year Old

The goal of this observational study is to compare the incidence of ARI and/or diarrheal disease associated with feeding different formulas with and without lactoferrin supplement in children of 2-3 years old. 200 children eligible for the study will be enrolled from two study sites and randomly assigned to two groups (a2 growing up stage 3 formula puls lactoferrin supplement, and Enfinitas growing up stage 3 formula) to feed for 90 days. About 160 children (80 for each group) are expected to finish the study, and data will be collected during the four visits across the study.Researchers will compare the two groups to see if there is significant decrease of the occurrence of diarrheal disease and/or acute respiratory infection for children fed with a2 growing up stage 3 formula puls lactoferrin supplement

Inclusion Criteria:Full term born children current aged 2-3 years oldBirth weight not less than 2500g (5lb 8oz)Consumes Milk or milk-based beverage regularly before recruitmentInformed consent signedParents or guardians of the infants committ not to participate in interventional clinical research during the interventionExclusion Criteria:Has a potential risk of metabolic or chronic disease; Fetal malformation; Or present with condition(s) that the investigator believes may affect the infant's ability to be orally fed, the infant's normal growth/development, or the infant's health evaluation.In-take prebiotics or probiotic continuesly 15 days before the recruitment.Growth problems or other protencial risks.Larger-gestational age (LGA) babies born to mothers with gestational diabetes (defined as newborns whose birth weight is above the 90th percentile of average - Treated with antibiotics 7 days before study intervention.