Energy intake during reproduction in captive common marmosets (Callithrix jacchus)

Area of Science:

• Primate reproductive biology
• Behavioral ecology
• Mammalian energetics

Background:

• Callitrichidae primates exhibit specialized traits and cooperative breeding systems.
• High reproductive costs are hypothesized for this group, potentially influencing social structures.
• Understanding these costs is crucial for evolutionary insights into primate reproduction.

Purpose of the Study:

• To investigate the reproductive costs in captive pair-living common marmosets (Callithrix jacchus).
• To analyze changes in energy intake and body weight during pregnancy and lactation.
• To assess the energetic demands on both females and males during offspring care.

Main Methods:

• Monitoring energy intake and body weight in adult marmosets during reproductive phases.
• Observing carrying behavior in relation to energetic expenditure.
• Comparing adult physiological responses to reproductive demands in a captive setting.

Main Results:

• Female marmosets significantly increased energy intake (up to 100%) during lactation but lost weight, indicating high energetic costs.
• Pregnancy did not lead to a compensatory increase in female energy intake.
• Male marmosets showed no significant changes in energy intake or body weight despite extensive carrying behavior.

Conclusions:

• Reproductive costs, particularly during lactation, are substantial for female marmosets.
• Energetic demands during reproduction may be mitigated by behavioral adjustments towards less costly activities.
• Captivity may influence the expression of these reproductive costs and associated behaviors.