A healthy diet for guinea pigs

Guinea pigs need:

• Fresh clean drinking water continuously, checked twice daily. Ensure water doesn't freeze in winter. Without water guinea pigs become seriously ill.  
• Good quality hay always available which should constitute the majority of their diet. Their digestive systems need grass and/or hay to function properly.  
• Fresh grass/vegetables as frequently as possible, ideally daily. They naturally graze, eating only grass/herbs/some plants (e.g. dandelion/groundsel) for long periods both day and night. Their teeth grow continuously, needing wearing down and keeping at the correct length/shape by eating grass/ hay/leafy green plants. Incorrect diets can cause serious dental disease.  
• A fresh portion of grass-based guinea-pig pellets daily, as per manufacturer's instructions. These provide essential Vitamin C, which is destroyed over time and quickly with exposure to air. Fresh pellets must be given daily. Don't just top up the bowl, ensure pellets are used by the best before date. Guinea pigs have special dietary needs and must have sufficient Vitamin C in their diet.  
• Fresh grass/leafy greens e.g. kale/broccoli (excellent Vitamin C sources) daily. Don't give citrus fruits.   
• Larger pellet portion if growing/pregnant/nursing/underweight. Vets give dietary advice.  
• Safe, washed leafy greens/weeds daily. Some plants are poisonous to guinea pigs.  
• To avoid sudden changes in diet; never feed lawnmower clippings. These upset digestive systems causing illness.  
• Root vegetables like carrots, or fruit e.g. apples, only in small amounts as treats, e.g. apple quarter. Don't feed other treats as these may harm your guinea pigs. They don't naturally eat cereals/root vegetables/fruit.  
• Feeding quantities adjusted preventing them becoming underweight/overweight. Quantities guinea pigs need depend on age/lifestyle/general health. They become overweight and may suffer if eating more than needed.  
• The amount they eat/drink monitored. If these habits change, droppings get less/stop or soft droppings stick to their back end/lie around the cage, consult your vet immediately as they could be seriously ill. Guinea pigs produce two dropping types' hard dry pellets, and softer moist pellets they eat directly from their bottom and are dietary essentials.