Giraffes in the United States

Of the three (sub)species of Giraffes kept in the United States, the Masai, Reticulated, and Rothschild, I've heard that most of the endangered Reticulated and Rothschild Giraffes are hybridized. So I was wondering, are there any facilities in the US that actually have purebred Rothschild and Reticulated Giraffes?

 

There is already a thread on this topic. Here is the link: http://www.zoochat.com/593/rothschilds-reticulated-giraffes-118911/