Early postnatal physical and behavioural development of degus (Octodon degus)

Area of Science:

• Developmental biology
• Animal behavior
• Comparative psychology

Background:

• Octodon degus, commonly known as degus, are rodent species.
• Understanding early developmental milestones is crucial for various research fields.

Purpose of the Study:

• To document the developmental milestones of Octodon degus from birth to 10 days of age.
• To assess the suitability of degus as a model organism for developmental studies.

Main Methods:

• Observation of 6 litters of degus from birth to 10 days.
• Assessment of physical characteristics (eyes, fur, teeth) and motor skills (walking, self-righting, vocalization).
• Behavioral testing in an open field apparatus to evaluate activity, exploration, and distress vocalization.

Main Results:

• Newly-born degus (14.6g mean weight) possess open eyes, fur, and teeth, and can walk within 3-4 hours.
• Functional grooming behaviors observed by day 1-2; solid food ingestion begins by day 6.
• Increased activity and exploration in the open field, with decreased distress vocalization after day 4-5.

Conclusions:

• Octodon degus display a high degree of precocial development at birth, surpassing previous reports.
• Their advanced neonatal development and immediate testability make them a valuable model for studying developmental processes.
• Further research is warranted to explore their potential in developmental toxicology and behavioral neuroscience.