Rat pups are born altricial, meaning they are completely dependent on their mother for warmth, food, and protection in the first few weeks. Their journey from a helpless newborn to a weaned juvenile is a rapid process. Understanding this early period is important for anyone raising these young animals, as initial care sets the foundation for their future health.
Physical Characteristics of a Newborn Rat
At birth, rat pups are underdeveloped and fragile. They are born completely naked, without any fur, and their skin is a translucent pink. Their eyes are fused shut, and their ear canals are sealed, rendering them both blind and deaf to the world.
Weighing only a few grams, their limbs are tiny and not yet capable of supporting their body weight, allowing only for a slight wiggling motion. This helplessness means their survival is entirely contingent on the care provided by their mother.
Developmental Timeline
The first week of a rat pup’s life is marked by steady changes. Around day three to five, their ear canals will open, allowing them to start perceiving sound. A fine, downy fuzz begins to cover their pink skin between days five and seven, which thickens into a proper coat of fur. This new coat helps with thermoregulation, though they still huddle for warmth.
The second week brings more milestones. Between days 12 and 15, a pup’s eyes will open. They transition from crawling to taking their first wobbly steps. They also begin to explore the immediate vicinity of the nest, driven by increasing curiosity.
By the third week, the pups are fully mobile, actively playing with their siblings, and learning social behaviors. They start to sample solid foods by nibbling on whatever their mother is eating, although they still primarily nurse for nutrition. Weaning is completed by the fourth week, at which point they are independent and socially interactive juveniles.
Maternal Care and Nest Life
The mother rat, or doe, provides care tailored to the needs of her developing litter. She spends the majority of her time in the nest nursing the pups, especially during the first two weeks. The mother’s arched-back nursing posture provides tactile and thermal stimulation, and this physical contact is a source of comfort.
Beyond feeding, the mother is meticulous in her grooming. She frequently licks her pups to keep them clean and to stimulate their bodies to urinate and defecate, a function they cannot perform on their own initially. If a pup wanders too far from the nest, she will retrieve it.
Pups instinctively huddle together in a pile, a behavior that helps them conserve body heat. This physical contact with littermates and the mother is a source of sensory input that shapes their early neurobehavioral development.
Caring for an Orphaned Rat Pup
Discovering a lone or abandoned rat pup requires prompt action. The best course of action is to immediately contact a licensed wildlife rehabilitator or a veterinarian experienced with small mammals. These professionals have the resources and knowledge to provide the specialized care required for survival. Attempting to raise an orphan without proper guidance can do more harm than good.
While awaiting professional help, you can provide basic emergency care. The priority is warmth, as a cold pup cannot digest food. A heating pad set on low and placed under one half of a small container with bedding provides a heat source. The pup must be able to move away from the heat if it gets too warm.
For feeding, cow’s milk is unsuitable. A kitten or puppy milk replacer formula is necessary. Feeding should be done with a tiny syringe or a specialized nursing nipple. After each feeding, gently stimulate the pup’s genital area with a warm, damp cotton ball to prompt urination and defecation, mimicking the mother’s licking.