Neonatal odor conditioning

Neonatal odor conditioning

Before conditioning, only foster mother mice were pre-exposed to the odor in a cage (26×40×18 cm) for 10 min, three times a day for 3 consecutive days, to habituate the odor and paper. A filter paper (2×2 cm) spotted with a test odorant was placed near the mice. After pups were born, they were grown with the foster mother in the experimental room until the test. For conditioning, a filter paper was put 1cm away from the nest then pups were exposed to the odor for 10 min with the foster mother, three times a day for 3 consecutive days. Odor concentration was 0.5 μl of 20 mM for vanillin (VNL) or 100 mM for 4-methyl-thiazole (4MT) (Wako).