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PubMed · 9227839

Altered behaviour in hamsters conceived and born in hypergravity.

H N Sondag·H A de Jong·W J Oosterveld
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Abstract

We studied vestibular function in 37 hamsters (1 month old) conceived and born in either hypergravity (n = 21) or normal gravity (n = 16). Four groups were made: (1) HL group: 20 weeks in 2.5 G and 14 weeks in 1 G; (2) HS group: 4 weeks in 2.5 G and 30 weeks in 1 G; (3) CON group: 34 weeks in 1 G; and (4) ROT group: 4 weeks in 1 G, 16 weeks in rotation in 1 G, at the centre of the centrifuge and 14 weeks 1 G. When the hamsters were 4 weeks old, their locomotor activity, swimming ability, and air-righting was assessed. We found that HL and HS hamsters had no disturbances during locomotion in 1 G but their swimming ability was disturbed (swimming underwater, circling, and decreased speed of swimming). The HL hamsters showed less activity during 2.5 G and showed fewer correct air-rightings than the other groups. Differences between groups in swimming ability and the number of correct air-righting responses remained even after 3 months of normal gravity. Based on these findings, we suggest that the persistent behavioural disturbances are caused by the embryonal development of the hamsters in a hypergravity environment. Furthermore, hypergravity and rotation each have a different effect on behaviour.

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Age FactorsAnimalsBehavior, AnimalBody WeightCricetinaeHypergravityLocomotionTask Performance and AnalysisVestibular NucleiJournal ArticleResearch Support, Non-U.S. Gov't

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H N Sondag, H A de Jong, W J Oosterveld. 1997. Altered behaviour in hamsters conceived and born in hypergravity.. https://doi.org/10.1016/s0361-9230(97)00008-7

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