its dr vivek
one thing what i want to tell u is that baby used to pass stool after feed is normal process because of gastro-colic
second thing if your baby is feeding well and passing urine and gaining weight not to worries .
one possibility is there antibiotic at initially it was acute diarrhea
and now this may be antibiotic associate diaarhea . but stool culture and Routine is normal so not to worries .
syp zinc 10mg /day
continue breast feeding