Good question. I don't know much about these creatures but I'll give you some links at the end. A Jird is an exotic rodent. It is a member of the same family as pet store gerbils. They are a lot bigger than normal gerbils (about the size of a rat).

Like the gerbil they come from arid (dessert) environments. They like dust baths (like chinchillas and degus and other dessert rodents). The live in groups in the wild.

They eat the same things as other rodents do. A gerbil food would suffice (with added things like fruit, mealworms, nuts, etc. for variety every now and then, just not too often).

Many say they make even better pets than the standard gerbil. Their larger size makes them better for kids. They are easier for small hands to hold on to. Their large size also makes them a little (emphasize on the little) more resistant to the occasional squeeze from an excited child. They are supposed to have a very easy going temperament.

That being said, I've never seen one for sale locally. I'm under the impression that they are relatively rare in the American pet trade. Most of the information I have linked is from the United Kingdom where they seem to be very popular. There are several species that are popularly kept as pets there (care requirements are all similar but they look a little different).

In the states I've only heard a few vague references to them. However, if you have a Jird breeder in your area then sure you can keep them as pets! The breeder would also be a wonderful source of more Jird information.

Jird Observations | Persian Jird (tips on general care and handling) | UK Gerbil Society : Jird info (lots of photos, including the above) | Jird History and Care