Activity and melatonin rhythms among rats with recourse to dark burrows.
D000818:Animals; D002940:Circadian Rhythm; D003624:Darkness; D004327:Drinking Behavior; D004780:Environment, Controlled; D005247:Feeding Behavior; D008297:Male; D008550:Melatonin / Q000378:metabolism*; D009043:Motor Activity; D010870:Pineal Gland / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains
D008550:Melatonin