[19]

MATERNAL BEHAVIOUR UNDER HYPERGRAVITY CONDITIONS IN CD 1 MICE.  M Simeoni, D Santucci and E Alleva.  Behavioural Pathophysiology Section, Laboratorio di Fisiopatologia di Organo e di Sistema, Istituto Superiore di Sanita, Viale Regina Elena 299, I-00161 Rome Italy.

Investigations in the micro-gravitational environment of space will potentially provide us with new insights into biological processes, as well as a capacity to safeguard the health of animals and humans in future space ventures. Hyper- or micro-gravity induced changes in maternal behavour will in part determine the mother нs success in rearing young under these conditions To identify maternal behavioral items vulnerable to altered gravity we examined the effects of hypergravity exposure during lactation in mice, a species whose small body size makes them particularly suitable for use in space biology. Primiparous and multiparous CD-1 females were exposed with their pups to a centrifugal force of 2g for 1 hour daily from postnatal day (PND) 3 to 10, and detailed behavioural observations recorded on PND 3, 5, 7 and 10 over the hour before, during, and after rotation. Preliminary analyses (PND 3 and 5) indicate that certain maternal behaviours such as licking the pups and nest-building are repressed under hypergravity conditions. Results also suggest that maternal experience is a factor in the behavioural response to hypergravity, with terziparous dams spending less time in contact with pups than primiparous mothers while rotating on PND 5. A detailed understanding of the behavioural response to hypergravity in nursing mothers will aid in our attempts to optimise the nest environment in future altered-gravity experiments on space missions.