Introduction
Guinea pigs are herbivorous rodents with unique dietary requirements. A proper diet is crucial for their health, longevity, and well-being. This guide covers all aspects of guinea pig feeding and nutrition.
Recommended Diet Types
Hay (Unlimited)
Timothy hay or orchard grass should be available 24/7. Hay provides essential fiber for digestion and dental health. Alfalfa hay is only for pregnant or nursing sows and young guinea pigs under 6 months due to high calcium content.
Pellets (Limited)
High-quality guinea pig pellets fortified with vitamin C (30-50 mg per day per adult). Avoid mixes with seeds, nuts, or dried fruits. Feed 1/8 cup per adult guinea pig daily.
Fresh Vegetables (Daily)
Leafy greens like romaine lettuce, kale, cilantro, and bell peppers are excellent. Provide 1 cup per guinea pig per day, divided into two servings. Avoid iceberg lettuce and high-calcium veggies like spinach in excess.
Fruits (Occasional Treats)
Fruits are high in sugar; limit to 1-2 tablespoons per week. Options: apple (no seeds), blueberries, strawberries, melon.
Water
Fresh, clean water must be available at all times via a water bottle, changed daily.
Portion Sizes and Daily Caloric Needs by Age, Size, and Activity
| Life Stage | Weight | Daily Calories | Hay | Pellets | Vegetables |
|---|---|---|---|---|---|
| Young (0-6 months) | 200-600 g | ~60-80 kcal | Unlimited (alfalfa + timothy) | 1/8 cup alfalfa-based | 1/2 cup |
| Adult (6 months-5 years) | 700-1200 g | ~70-100 kcal | Unlimited (timothy) | 1/8 cup timothy-based | 1 cup |
| Senior (5+ years) | 700-1200 g | ~60-80 kcal | Unlimited (timothy) | 1/8 cup (adjust if weight loss) | 1 cup |
Activity level: Active guinea pigs may require slightly more; sedentary ones less. Adjust pellets accordingly.
Feeding Frequency and Schedule
Guinea pigs are grazers. Offer fresh hay 24/7. Provide pellets once daily in the morning. Fresh vegetables should be given twice daily (morning and evening). Fruits as treats 2-3 times per week.
Essential Nutrients
- Protein: 16-20% of diet. Hay and pellets provide sufficient protein.
- Fat: 2-4% of diet. Minimal fat needed; avoid excessive seeds/nuts.
- Carbohydrates: High fiber from hay, some from veggies and limited fruit.
- Fiber: Essential; 20-25% crude fiber from hay prevents GI stasis.
- Vitamin C: Guinea pigs cannot synthesize vitamin C. Requirement: 10-30 mg daily for adults, up to 50 mg for pregnant/lactating. Supplement through fresh veggies (bell peppers, kale) or vitamin C drops in water.
- Calcium: 0.5-1% of diet. Excess can cause bladder stones. Avoid high-calcium foods like alfalfa hay for adults.
- Vitamin D: From sunlight or fortified pellets.
Foods and Ingredients Toxic or Harmful
- Dairy products: Lactose intolerance.
- Meat/Animal products: Not digestible.
- Seeds, nuts, grains: High fat and choking risk.
- Avocado: Toxic (persin).
- Onions, garlic, leeks: Damage red blood cells.
- Raw beans, potatoes: Toxins.
- Chocolate, caffeine: Methylxanthines toxic.
- Sugar-sweetened foods: Obesity, dental issues.
- Iceberg lettuce: Low nutrition, possible diarrhea.
- Rhubarb leaves: Oxalic acid toxic.
Water Intake Recommendations
Guinea pigs drink 100-300 ml per day on average. Ensure water is fresh and changed daily. Use a water bottle with a metal ball tip to prevent spills. Check that the bottle works properly.
Beneficial Supplements
- Vitamin C: Essential supplement if diet lacks greens. Use tablets or liquid (avoid adding to water as it degrades quickly).
- Oxbow Critical Care: For sick or anorexic guinea pigs.
- Probiotics: Beneficial after antibiotic treatment (e.g., Bene-Bac).
- Digestive enzymes: Not typically needed unless recommended by vet.
Avoid multivitamins with added sugars or unnecessary minerals.
Feeding Differences: Young, Adult, and Senior
Young (0-6 months)
- Alfalfa hay for calcium and protein.
- Alfalfa-based pellets.
- Introduce vegetables gradually from 2 weeks.
Adult (6 months-5 years)
- Timothy hay mainstay.
- Timothy-based pellets (low calcium).
- Vegetables low in calcium and oxalates.
Senior (5+ years)
- Monitor weight; increase pellets if underweight.
- May need softer veggies if dental issues.
- Continue vitamin C supplement.
Signs of Healthy vs. Poor Diet
Healthy Diet Signs
- Shiny, smooth coat.
- Active and alert.
- Normal, well-formed droppings (greenish-brown, oval).
- Healthy weight: ribs not visible but easily felt.
- Teeth even and not overgrown.
Poor Diet Signs
- Lethargy, hiding.
- Weight loss or obesity.
- Diarrhea or constipation (abnormal droppings).
- Scurvy: rough coat, swollen joints, bleeding gums, reluctance to move.
- Overgrown teeth due to insufficient hay.
If you notice any signs of illness, consult a veterinarian experienced with guinea pigs.