Mouse and Rat Care: Vet‑Approved 2025 Guide by Dr Duncan Houston 🐁🩺

Introduction

This extensive 2025 guide from Dr Duncan Houston provides expert advice on caring for pet mice and rats. Whether you're starting with a single mouse or managing a colony of rats, this guide covers everything from nutrition and habitat setup to handling techniques and disease prevention. Designed for older children and adult caretakers, this guide empowers you to foster healthy and happy rodent companions. 🐭🐀

1. Understanding Your Pets

Mice and rats are intelligent, social, and responsive rodents. While often viewed negatively, as pets they can become gentle, engaging companions. Pet rodents may sleep during the day and be active at night—but with care, their routine can align with yours. Though timid initially, mice and rats rarely bite when handled gently from a young age. They enjoy exploring, burrowing, and interacting, making them delightful to watch and care for.

2. Nutrition & Diet 🍽️

Staple Diet

The foundation of health for rodents is a high-quality pelleted rodent ration, offering balanced nutrition—around 14‑19% protein and 4‑11% fat depending on growth stage. Dr Houston emphasizes that pellets provide consistent nutrition, unlike seed-based diets which are high in fat, cholesterol, and prone to spoilage.

Treats & Supplements

• Use seed-based mixes only as occasional treats.
• Human foods should be offered sparingly: small amounts of lean meats, cooked pasta, fresh vegetables (e.g., peas, corn, squash), and occasional nuts or eggs.
• Avoid excessive high-fat snacks—rats are especially prone to obesity and related diseases.

Always introduce new foods gradually to prevent digestive upset. Rodents eat around 5‑15 g food and 10‑15 ml water per 100 g body weight daily—rats consume more water relative to their size than mice.

Hydration

Fresh water must be available at all times via sipper bottles (properly positioned) or heavy bowls. Change and clean water daily to prevent contamination.

3. Housing & Environment 🏠

Cage Materials & Design

Recommended cage materials include wire, stainless steel, and durable plastic. Avoid wood-based bedding that can harbor mold. For ventilation, a solid-bottom cage with rounded corners and secure wire top is ideal. Glass tanks may be used if adequately ventilated.

Bedding & Nesting

• Use shredded paper, processed corn cob, or paper bedding that’s non-toxic and dust-free.
• Avoid cedar/chlorophyll-scented shavings due to respiratory and liver concerns.
• Provide ≥1 inch bedding depth for burrowing, plus nesting materials like cotton, shredded tissue, or paper towels.

Space Requirements

• Mice: ≥15 in² floor space and 5 in cage height per adult mouse.
• Rats: ≥40 in² floor space and 7 in height per adult rat.
• Breeding groups or multiple animals require larger multi-level cages with multiple resources (food, water) to prevent aggression.

Climate & Lighting

Ideal temperature: 65‑80 °F (18‑27 °C), humidity 40‑70%. A 12h light/dark cycle supports natural activity rhythms.

4. Social Structure & Handling 👐

Social Needs

Rodents are social by nature. Mice and rats thrive in groups—with rats especially flourishing in groups of 3‑4. Provide ample space and enrichment to support socialization. Monitor for bullying; separate aggressive individuals when needed.

Handling & Safety

• Always scoop mice and rats into hands or containers to avoid territorial defense.
• For mice, lift gently by base of tail or scoop into clear tubes.
• For rats, support by the body under the ribcage; avoid scruff handling.
• Avoid grabbing the tip of the tail to prevent injury.
• Never awaken sleeping animals abruptly—they may bite out of fear.

5. Breeding Basics (If Applicable)

Sexing Young Rodents

Males show a wider anogenital distance than females, and mature males often display a prominent scrotum. Females exhibit noticeable nipples.

Housemates vs Breeding Pairs

Mice: group adult females; males can fight and should live with one or more females only. Rats: males and females often cohabitate peacefully.

Reproductive Cycles

• Female mice: mature ~50 days, estrous every 4‑5 days, can breed within 24h postpartum.
• Female rats: mature ~65 days, estrous every 4‑5 days, postpartum breeding possible but monitor male presence.

Gestation & Litters

• Mice: ~3 weeks gestation (up to 31 days), litters of 10‑12; wean ~3 weeks.
• Rats: ~3 weeks gestation, litters of 6‑12; wean ~3 weeks.

Avoid disturbing the nest for the first few days after birth to reduce stress and maternal abandonment.

6. Common Diseases & Treatment 🩺

Chronic Mycoplasma pulmonis (Murine Pneumonia)

This chronic respiratory infection presents with sneezing, labored breathing, squinting, discharge, and sometimes head tilt. Long‑term antibiotic therapy is usually required. Isolation during treatment helps reduce spread. The disease is common and often subclinical.

Sendai Virus (Mice)

Rare in pets but possible in colony-bred mice—symptoms include labored breathing and poor coat condition. No cure exists; supportive care and isolation are essential.

Sialoacryadenitis (Rats)

A viral disease causing swollen eyes, squinting, sneezing, and nasal discharge. Usually self-limiting but may increase risk of secondary respiratory infections.

Tyzzer’s Disease (Rodents)

Caused by Bacillus piliformis. Lethargy, hunched posture, poor appetite, diarrhea. Young and stressed animals at risk. Prevention is vital through sanitation and quarantine.

Handling Other Health Issues

• Injuries & Wounds: Especially from aggressive peers—clean and vet treat promptly.
• Parasites: Mites can cause itching and hair loss. Diagnosis by skin scraping and treatment with vet-prescribed medication.
• Tumors: Mammary and pituitary tumors common in rats; spaying/neutering helps reduce incidence.
• Obesity & Metabolic Issues: Prevention through diet control and avoiding free-feeding seed mixes.

7. Prevention & Wellness Care

• Feed balanced pellet diet, limit treats.
• Maintain clean, spacious, and enriched housing.
• Regular handling and social interaction.
• Quarantine new animals (4–6 weeks) to prevent disease introduction.
• Schedule veterinary wellness checks—monitor for respiratory or tumor development.

8. Daily Care Checklist

9. Final Vet‑Approved 2025 Tips

• 🐭 Provide high-quality pellet diet and fresh water.
• 🏠 Ensure spacious, well-ventilated, enriched housing.
• 🤝 Handle gently, and socialize regularly.
• 🧼 Clean cage weekly and spot-clean daily.
• 🔬 Quarantine new rodents to prevent disease.
• ⚠️ Monitor for respiratory symptoms—seek vet care early.
• 🌡️ Maintain ideal temperature/humidity.
• 🚫 Avoid high-fat diets and maintain exercise.

Conclusion

With proper care—balanced nutrition, clean housing, handling, and disease prevention—pet mice and rats make affectionate, intelligent, and enriching companions. By following this comprehensive guide from Dr Duncan Houston, you can provide a safe, healthy, and stimulating environment for your rodent friends. 🐀💕

Further Support

For detailed veterinary insights on respiratory illness, parasites, or rodent medicine, download the Ask A Vet app or visit AskAVet.com 🎯

Disclaimer

Information is for educational purposes and does not replace veterinary diagnosis and treatment. Contact a qualified veterinarian for personalized care.