Many, if not most, lower quality guinea pig pellet mixes and treats are full of colorful nuggets, nuts, and seeds. If it's sold in pet stores and labeled for guinea pigs, it must be healthy, right? Wrong. These products are marketed to appeal to us humans, but nuts and seeds aren't actually part of a healthy diet for guinea pigs.
According to Dr. Kenneth Welle, an exotic vet at the University of Illinois Veterinary Teaching Hospital in Urbana, "Pretty diet mixes containing grains and seeds are disastrous ... Guinea pig digestive systems are designed for grass diets, which are high in fiber and low in carbohydrates. The sugars and starches in some diets can cause a change in the digestive bacteria, intestinal obstructions, and obesity."
What's so bad about seeds?
Most seeds are inappropriate for guinea pigs because they are fattening. While we may enjoy ice cream for dinner on occasion, we don't make this a habit because we know it's not good for us. Guinea pigs don't have the same self control, so it's up to us to make healthy choices for them. Pellet mixes that contain seeds can encourage selective eating. Guinea pigs will tend to pick out the tasty treats, but leave behind the healthy pellets.
Hard seeds, like pumpkin and sunflower seeds, can get stuck in the chompers and become a choking hazard. These types of seeds aren't safe to feed on their own or in bags of pellets. The healthiest guinea pig pellets don't look as exciting out of the bag, but they are the safest choice. Look for a plain, timothy-based pellet with stabilized vitamin C. Seeds just can't compete when it comes to fiber or nutrient content.
What about treats?
Skip the sugary nut and seed sticks. There are plenty of healthier treat options available your guinea pigs will appreciate even more. A little parsley can bring almost any pig to his knees. Have a sweet tooth in your herd? Offer a baby carrot or a few blueberries as a special reward. Of course, you can never go wrong with some healthy snackers.
If your guinea pig needs to put on weight, perhaps after recovering from an illness or surgery, there are still healthier and safer choices than nuts and seeds. A little extra fruit, oat hay, corn on the cob, raw rolled oats, flaked peas, or mashed pellets with 100% canned pumpkin (no sugar added) tempts most piggies and packs on the ounces quickly.
A note on safe seeds
Soft seeds, like those naturally found in cucumbers and tomatoes, are perfectly safe. There is no need to remove the "guts" of bell peppers, either. These seeds are soft and nutritious. On the other hand, hard seeds like apple, orange, or watermelon seeds can pose a choking hazard and should be removed before feeding.