What does a baby rat and mouse look like? - briefly
Newborn rats, called pups, are hairless, pink, and have closed eyes and ears, measuring about 1–2 cm in length; they develop fur and open their eyes within 10–14 days. Newborn mice, known as pinkies, are similarly hairless and pink, slightly smaller (≈0.5–1 cm), with closed eyes and ears that open around the same time as rat pups.
What does a baby rat and mouse look like? - in detail
Newborn rats, often called pups, are hairless at birth. Their skin appears pink or slightly reddish, covered with a thin, translucent membrane that protects the eyes. The eyes remain closed for the first 10–14 days, and the ears are flat against the head. Each pup measures approximately 2–3 cm in length (head‑to‑tail) and weighs between 1.5 and 3 g. The tail is short, naked, and almost invisible beneath the body. Limb buds are present, but movement is limited to weak twitches.
Newborn mice, referred to as pinkies, share many characteristics with rat pups but are smaller. Their bodies are about 1–1.5 cm long, weighing 0.5–1 g. The skin is similarly pink and hairless, with a faint covering of fine, downy fur that becomes noticeable after a few days. Eyes stay closed for the first 12–14 days, and ears lie flat. The tail is proportionally longer than the body, yet still hairless and barely discernible. Limbs are more developed than in rat pups, allowing slight crawling motions when stimulated.
Key visual differences:
- Size: rat pups are roughly twice the length and mass of mouse newborns.
- Fur onset: mice develop a fine coat earlier than rats.
- Tail visibility: rat pups have an almost invisible tail; mouse newborns have a slightly longer, more apparent tail.
Both species rely on maternal warmth, as they cannot regulate body temperature until the third week of life. Their appearance reflects this dependence, with minimal protective features at birth.