Guinea pig nutrition and why is hay so important, explains Andrea Kroftová

Let's start with a more general and basic question. Why is hay so important for guinea pigs?

Guinea pigs are herbivores, therefore hay is an essential building block of their diet. Hay has two main functions. First, it's used to grind the ever-growing teeth - they grow up to 1.5 mm a week. Second, it's a source of fibre, which is important for fermentation processes during digestion. In case of deficiency in fibre, the movement in a guinea pig's bowels slows down and the peristalsis comes to a stop. 

What about the dosage?

In order for the fluff ball to thrive, there must be constant access to loose hay. It's best to keep it in a hay rack. To give you an idea, an adult guinea pig eats up to 150 grams of hay for every kilogram of its weight a day. 

So what should an ideal diet plan for the small furry ball look like?

Apart from good-quality hay, there should be fresh water, which we mustn't forget about. Water in a bowl gets dirty quite quickly, therefore we use water bottles, which we refill every day. 

Guinea pigs also need fresh grass and vegetables. We don't have to force them to eat it as they love both of them. However, do be careful what vegetables you give them. They definitely mustn't be spoiled or frozen and always wash them before serving. Root vegetables such as carrots, celeriac, parsnips or beet are ideal. Unsuitable ones are those that are too watery or cause bloating.

During the green season, vegetables can be fully replaced by grass. The amount is important as well and it shouldn't replace the amount of consumed hay. Everything that the animal is offered should follow the golden hygiene rule: whatever they don't eat in one day should be thrown out.

What, besides vegetables, can the owner treat his pet with?

Fruit can also be used as a treat. To make the diet more varied we can also add a small amount of fresh or dried herbs such as dill, basil or mint. I don't recommend overdoing it with feed mixes in the form of pellets. One teaspoon a day is ideal. Guinea pigs are quite picky and can end up eating too much starch and protein, and not enough fibre, and suddenly we have a problem. When choosing a mix, it's important to read the ingredients, and other than fibre and protein we should also look at the content of calcium, phosphorus and natural (stabilised) vitamin C. Packaging in a protective atmosphere and transparent foil goes without saying. Also woody branches such as apple, pear or currents I can only recommend as a treat.

Is it necessary to adapt the nutrition to the guinea pig's life stages? 

Every animal has its specific needs in different stages of its life and they also change according to the environment in which we keep it. Outdoor guinea pigs require more food than their friends who are of the same age but live indoors. A growing individual needs more protein and calcium than an adult one. Also pregnant or lactating females need to gain more weight. In this case, however, we must monitor the pellet intake and the content of protein and sugar. They increase the risk of toxaemia.

Can I use food supplements as an extra treat for my pet? 

Vitamin C intake in feed is essential for guinea pigs as they cannot synthetize it. In order for its body to work correctly, a guinea pig needs approx. 10-20 milligrams for every kilogram of its weight. Guinea pigs in stressful situations, growing, sick or lactating females need an increased dosage of vitamin C. If necessary, we can use multivitamin drops for guinea pigs as a supplement. If the guinea pig doesn't have the possibility of an outdoor enclosure and natural sunlight, adding vitamin D is recommended.