Hyperthermia - overheating
Guinea Pigs originate from South America where they still live in the wild today. In the wild, guinea pigs tend to make their habitats in rocky areas, grasslands and forests. They are used to coping with relatively high environmental temperatures, upwards of 22°C/71.6°F, providing they have access to shade and fresh water. However, they can rapidly overheat, and apart from their ears and the soles of their teeth, they are densely furred, so find cooling down, when too hot, difficult.