Development of nocturnal behavior in albino rats.
D000367:Age Factors; D000818:Animals; D000831:Animals, Newborn / Q000254:growth & development*; D002940:Circadian Rhythm; D005106:Exploratory Behavior; D009043:Motor Activity / Q000502:physiology*; D051381:Rats; D012737:Sex Factors; D012919:Social Behavior; D013997:Time Factors; D014886:Weaning