Not true. Guinea pigs are rodents.
From wikipedia:
http://en.wikipedia.org/wiki/Guinea_pigs
Guinea pigs are large for rodents, weighing between 1 and 2.5 pounds (700–1200 g), and measuring 8–10 inches (20–25 cm) long.[24] They typically live an average of four to five years, and occasionally as long as eight years.[25] According to the 2006 Guinness Book of Records the longest living guinea pig survived 14 years, 10.5 months.[26]
In the 1990s, a minority scientific opinion emerged proposing that caviomorphs, such as guinea pigs, chinchillas and degus, are not actually rodents and should be reclassified as a separate order of mammals (similar to lagomorphs).[27][28] Subsequent research using wider sampling has restored consensus among mammalian biologists that the current classification of rodents as monophyletic is justified.[29]
They look like rats to me so I wouldn't eat one with any sort of vegetable or wine. But that is just me.