SEX DIFFERENCES IN NOVEL OBJECT RECOGNITION WITH SIMILAR OBJECTS IN MOUND-BUILDING MOUSE, MUS SPICILEGUS

• Published in: Comptes rendus de l'Academie bulgare des Sciences Vol. 69; no. 5; p. 593
• Main Author: Simeonovska-Nikolova, Daniela M
• Format: Journal Article
• Language: English
• Published: Bulgarian Academy of Sciences 01.01.2016
• ISSN: 1310-1331

There is much evidence about male superiority in spatial navigation in rodents, but sex differences in non spatial memory are not well determined. In this connection, the aim of this study was to assess the ability of wild male and female M. spicilegus to discriminate the identity of similar objects by Novel Object Recognition test. The subjects were adult M. spicilegus, captured from a wild population in Northern Bulgaria. The experiments with each mouse were carried out in an open field arena during three consecutive days. Twenty-four hours after habituation (the first day) the mice were exposed to the familiar arena with two identical objects. On the third day, they were allowed to explore the open field in the presence of the familiar object and a novel object, which was similar to the familiar object. The time spent exploring each of the objects was quantified and exploration of each object was expressed as a percentage of the total exploration time. Analysis using one-way ANOVA revealed a significant difference between the sexes regarding the period of time spent with the novel object. The female mice spent a significantly greater percentage of time exploring the novel object than the familiar object in comparison to males. It can be assumed that female advantage for memory of object feature reflects their ability to encode information about objects in natural habitats and probably are associated with their phylopatry.Key words: novelty, sex difference, novel object recognition, Mus spicilegus