The phrase "full feeding" means providing enough food or nourishment to someone or something so that they are completely satisfied and have enough energy. Full definition
... This baby is on a 3 hour routine and takes full feedings starting at 7 a.m.... after her 1:00 feeding, I'll lay her down around 2:00. (ezzo.info)
If the baby is sleepy, work to keep them awake so that they get full feedings. (americanpregnancy.org)
I had planned all along to donate her surplus milk as she wasn't on full feeds and my freezer stash was growing bigger every day. (breastfeedingtoday-llli.org)