Effects of differential early experience upon parental behavior in Mus musculus.

Infant mice, reared with both parents were subjected to 1 of 4 different early experience contingencies at 3, 6, 9, and 12 days of age. Observation of parental behaviors following return of the pups to the nest revealed that mothers attended more to pups subjected to intermediate levels of stress, with the differences in maternal behavior persisting across the age span without change. Fathers exhibited marked changes in responsiveness to young across the ages observed, with their attention to young correlating directly with rate of ultrasonic calling by the young.