Olfactory Preferences of Inbred Mice (Mus Musculus) for Their Own Strain and for Siblings: Effects of Strain, Sex and Cross-Fostering

Abstract

1. Mice of two inbred strains (C57 BL 6/J and SEC I ReJ) were tested for their preferences for the smells of bedding used by mice of the opposite sex of the same two strains. 2. C57 males and females showed no significant preference between the smell of C57 and SEC and this result was unaffected if the mice were reared by SEC foster-parents. 3. SEC males and females preferred the smell of SEC to the smell of C57 and this result was unaffected if the mice were reared by C57 foster-parents. 4. Males of both strains preferred the smell of non-siblings of their own strain to the smell of siblings. Rearing by foster-parents of the other strain reversed this preference; the males then preferred the smell of siblings. 5. C57 females preferred the smell of siblings to the smell of non-siblings of the same strain and this result was unaffected by rearing by SEC foster-parents. 6. Female SEC showed no significant sibling preferences and this result was unaffected by rearing by C57 foster-parents. 7. The results are consistent with the idea that mice prefer a slight degree of unfamiliarity in the smell of the opposite sex but they also suggest that what was judged as unfamilar differed between the two strains. 1. Mice of two inbred strains (C57 BL 6/J and SEC I ReJ) were tested for their preferences for the smells of bedding used by mice of the opposite sex of the same two strains. 2. C57 males and females showed no significant preference between the smell of C57 and SEC and this result was unaffected if the mice were reared by SEC foster-parents. 3. SEC males and females preferred the smell of SEC to the smell of C57 and this result was unaffected if the mice were reared by C57 foster-parents. 4. Males of both strains preferred the smell of non-siblings of their own strain to the smell of siblings. Rearing by foster-parents of the other strain reversed this preference; the males then preferred the smell of siblings. 5. C57 females preferred the smell of siblings to the smell of non-siblings of the same strain and this result was unaffected by rearing by SEC foster-parents. 6. Female SEC showed no significant sibling preferences and this result was unaffected by rearing by C57 foster-parents. 7. The results are consistent with the idea that mice prefer a slight degree of unfamiliarity in the smell of the opposite sex but they also suggest that what was judged as unfamilar differed between the two strains.