Effect of aging on species-typical behaviors in senescence-accelerated mouse.

The species-typical behaviors have been extensively studied, especially in the rodents. But little is known about whether the aging impacts on these species-typical behaviors. In the present study, the species-typical behaviors, including burrowing, hoarding and nesting, were assessed in the accelerated senescence-prone mouse 8 (SAMP8, P8) and the control strain senescence-resistant mouse 1 (SAMR1, R1). Total 147 SAM mice including 74 P8 mice and 73 R1 mice were grouped according to the age, 3, 7 and 11 months, respectively. In the hoarding test, an age-related increase was observed in the both P8 and R1 mice, whereas in the burrowing task, the age-related increment only took place in the P8 mice. The nesting ability in the P8 mice at different ages was inferior to that in the age-matched R1 mice, and the 3-month P8 mice showed the poorest nesting ability. The principal component analysis revealed that the burrowing, hoarding and nesting tests detected the different aspects of species-typical behaviors respectively for all mice combined. Our findings indicated that all tasks of hoarding, burrowing and nesting could detect the aging effect in the P8 mice, whereas, only the hoarding test could detect the aging effect in the R1 mice. These different species-typical behaviors were dissociable.