Effects Of Age And Sex On Species-typical Behaviors And Abilities Of Learning And Memory In C57BL/6 Mice

Objective To explore the effects of age and sex on species-typical behaviors and recognitive memory ability, and whether there is consistency in the decline of lerning and memory ability in C57BL/6 mice in the six-arm water maze (RAWM) and Morris water maze (MWM) test.Methods C57BL / 6 mice were used. The task battery of species-typical behaviors consists of burrowing, hoarding and nesting. The RAWM and MWM were used to test the spatial abilities of learning and memory, and novel-object recognition task was used to test the recognition memory.Results The results showed: 1) in the tests of the species-typical behaviors, the burrowing behavior was not significantly impaired, but the nesting ability was significantly declined in the old mice. The burrowing behaviors in the both old and adult male mice were significantly suppressed compared to the age-matched female mice. The nesting ability in the old male mice was significantly declined compared to the old female mice. There was nearly no hoarding behavior in the both old and adult C57BL / 6 mice; 2) In the both RAWM and MWM, the spatial learning and memory declined in the old group, however, there is no correlation between the performances in the MWM and the RAWM; 3) In the novel-object recognition task, there was nearly no exploring behavior in half of mice. Conclusion The results suggested: 1) the nesting was a good test to detect the effects of age and sex in the old C57BL/6 mice, and the burrowing was useful to test the effect of sex in the adult and the old C57BL/6 mice, but the hoarding test was no value to evaluate the effects of both age and sex in the C57BL/6 mice; 2) both RAWM and MWM were of excellent spatial tasks for measuring age-related impairment of learning and memory in mice, but they involved in different neural circuits. To explore the mechanism of the age-related decline of learning and memory, it's better to use both tasks simultaneously; 3) the novel-object recognition task was valueless to evaluate the effects of both age and sex on the nonspatial learning and memory ability in C57BL / 6 mice.