Maternal Preference in Adolescence

One of the earliest and most important social bonds for many mammals is the bond formed with their mother. Mothers provide essential benefits for offspring development and survival, but what happens to this bond when animals gain independence during adolescence?

In this research, we investigated whether adolescent mice (postnatal day 26) retain the ability to recognize and prefer their mothers after weaning. We further examined the strength of this bond using an acute immune activator, lipopolysaccharide (LPS), to understand how immune challenges might alter social preferences.

The Agora Maze SocioBox Method

This study employed the Agora SocioBox, a multi-chamber social behavior task that allows for a more nuanced assessment of social recognition and preference. The apparatus consists of a central open arena connected to multiple compartments, each temporarily housing different stimuli. This setup enables researchers to observe how mice interact with various social and non-social stimuli simultaneously, providing a more comprehensive understanding of social behavior dynamics.

The Agora Maze SocioBox apparatus showing the central arena with multiple chambers for different stimuli. You can read more about this methodology in this research alert from Ugo Basile.

Key Findings

In our research, the five-chamber social preference task (the AGORA) contains:

The biological mother
A sex- and age-matched novel mouse
A sex- and age-matched sibling
A novel object
An empty chamber

Our findings reveal that adolescent mice exhibit a strong maternal preference, which was significantly greater than chance and higher compared to any other social or non-social stimuli.

While LPS exposure reduced the time spent investigating all stimuli, adolescent maternal preference was not significantly altered by LPS exposure, demonstrating the resilience of this social bond. These effects were especially pronounced in females, while subtle shifts towards novel exploration began to emerge in males by postnatal day 26.

Implications

The novel multi-chamber task employed in this study offered a more nuanced understanding of how social bonds evolve and vary across sex. Although mice are typically not considered to form strong, enduring social bonds, the current findings reveal that adolescent mice show a robust preference for their mother, one that remains resilient to early-life immune activation. This shifts the narrative around mouse sociality and highlights the persistence and importance of maternal bonds even after weaning.

See the full research article: (Slamin et al., 2025)

One of the earliest and most important social bonds for many mammals is the bond formed with their mother. Mothers often provide essential benefits for offspring development and survival. Growing evidence suggests that this social bond is retained even when animals gain independence, such as during the juvenile period immediately following weaning. Here, we investigated whether or not juvenile mice (postnatal day [P]26) retain the ability to recognize and prefer their mothers post-weaning. We further investigated the strength of this bond using an acute immune activator. On P26, male and female C57BL/6J mice were intraperitoneally injected with the endotoxin lipopolysaccharide (LPS) or saline control (0.5 mg/kg). Four hours later, mice were subject to a five-chamber social preference task (the AGORA) containing their biological mother, a sex- and age-matched novel mouse, a sex- and age-matched sibling, a novel object, and an empty chamber. Our findings reveal that juvenile mice exhibit a strong maternal preference, which was significantly greater than chance and higher compared to any other social or non-social stimuli. While LPS exposure reduced the time spent investigating all stimuli, juvenile maternal preference was not significantly altered by LPS exposure. These effects were especially pronounced in females, while subtle shifts towards novel exploration began to emerge in males by P26. The novel multi-chamber task employed in the present study offered a more nuanced understanding of how social bonds evolve and vary across sex. The current findings suggest that juvenile mice have a robust social preference for their mother that is resilient to early-life immune activation.

The Agora Maze SocioBox Method

Key Findings

Implications

References

2025