A predator-proof enclosure to ensure their safety is essential. An appropriate enclosure is a hutch that is divided into two connecting compartments, one a wire mesh to allow access to natural light and fresh air, while the other is enclosed to provide protection against weather and a secure sleeping place. The floor of your guinea pig's hutch should be covered with newspaper, with a layer of bedding material like straw, grass, hay or shredded paper for warmth, comfort and to prevent pressure sores on your guinea pig's feet. Consider extreme weather conditions and ventilation when choosing a location for your hutch. Guinea pigs are extremely sensitive to the hot summer temperatures and may die of heat stroke if their hutch is not in a cool, shady position.
Feeding and nutrition is the most important factor in making sure your guinea pig stays healthy. Many commercial foods don't contain enough fibre (18 - 20% is required) and are too high in fats and sugars. Guinea pigs are herbivores so their diet should consist almost entirely of vegetable matter. Grass or hay [not lucerne] is an essential dietary component to ensure your guinea pig's health. Ideally, feed your guinea pig ad lib hay [not lucerne] and fresh green veggies such as Asian greens, spinach, bok choy, broccoli, herbs, sprouts, carrot tops, snow peas, brussel sprouts, or endive [lettuce and cabbage can cause diarrhoea]. Treats such as fruits, root veggies (carrots), capsicum and pellets should only be offered in small amounts. Guinea pigs cannot synthesise their own Vitamin C so it is important to feed then vegetables high in Vitamin C such as spinach, capsicum, tomatoes, parsley and some fruits. Fresh water should always be available using both a drip feed bottle and an open container.
Guinea pigs can be very prone to dental disease. Guinea pigs have teeth that constantly grow and require a good high fibre diet to help wear down their teeth. Providing your guinea pig with a well balanced diet with plenty of hay and grass helps with maintain healthy teeth. Regular check ups of your guinea pigs mouth are recommended as dental disease that is left to progress can have severe health consequences.
Entire female guinea pigs can get a high incidence of ovarian cysts so sterilisation of a non breeding female should be considered. Entire male guinea pigs can be very aggressive so sterilisation of non breeding males is strongly advised.