Anemia, MacrocyticErythrocyte IndicesErythrocyte VolumeErythrocytes, AbnormalVitamin B 12 DeficiencyFIGLU TestVitamin B 12Folic Acid DeficiencyAnemia, PerniciousErythrocyte CountMegaloblastsFolic AcidInfant, NewbornHematologic DiseasesAnimals, NewbornBenzenesulfonatesErythropoiesisHemoglobinsNiacinamidePhenylurea CompoundsInfant, Newborn, DiseasesNeonatal ScreeningPregnancy