From PetPlanet.com:

It is also very important to get your prairie dog spayed or neutered before he or
she enters their first winter. If you don't, your adoring pup will undergo a personality change once breeding season starts. He or she will become more distant and aggressive, and generally just won't be the prairie dog you've come to love. For this reason, among others, spaying or neutering is an absolute must.
Other sites say similar things. As long as your vet has done them before, I wouldn't worry abit, go ahead and have it done, Terkina'll be fine! I know female rabbits, who are similarly classified by many as rodents, have a tendancy to get ovarian cancer if they aren't spayed, so just in case it's similar in PD's, I'd go ahead with the procedure!