How much should a rat be fed per day? - briefly
An adult rat typically needs 20–30 g of high‑quality dry pellets daily, plus 1–2 tablespoons of fresh vegetables and unlimited water. Adjust the amount for age, activity, and health status.
How much should a rat be fed per day? - in detail
Rats require a diet that supplies roughly 15–20 kcal per 100 g of body weight each day. For a typical adult laboratory or pet rat weighing 300–350 g, this translates to 45–70 kcal daily. The exact amount depends on several variables.
- Age: Juvenile rats grow rapidly and need higher caloric density; a 6‑week‑old pup may require up to 80 kcal per day, while an adult’s requirement drops slightly.
- Sex and size: Males generally weigh more and thus consume more calories than females of the same age.
- Activity level: Rats that are highly active, housed in larger enclosures, or provided with exercise wheels burn additional energy and should receive 10–15 % more food.
- Health status: Illness, pregnancy, or lactation increase metabolic demand; pregnant or nursing females may need 25–30 % extra calories.
- Diet composition: A balanced mix of commercial rat pellets (approximately 3 kcal/g) combined with fresh vegetables, fruits, and occasional protein treats ensures nutrient adequacy. Over‑reliance on high‑fat treats can cause obesity, while excessive leafy greens may dilute caloric intake.
A practical feeding schedule:
- Offer a measured portion of high‑quality pellets in the morning, calculated at 0.8 g per 10 g of body weight.
- Provide a small serving of fresh produce (no more than 10 % of total diet by weight) in the afternoon.
- Remove uneaten food after 12 hours to prevent spoilage and limit waste.
Monitoring body condition scores weekly helps adjust portions. If a rat’s weight deviates by more than ±5 % from the target range, modify the daily amount by 5–10 % accordingly. Consistent access to clean water is essential; rats typically drink 15–30 ml per 100 g body weight each day.