The virus that we are infected with (HIV) to get AIDS is different to that of cats (FIV). There is not a similar virus that has adapted to attack canine cells. It is not that dogs have an inbuilt defense mechanism, and therefore studying them would not lead to useful information in regards to HIV/FIV. What is interesting is that FIV in cats is quite often asymptomatic, and also not necessarily life threatening. This is in fact more relevant to investigating ways to combat HIV. Currently, the way in which HIV infects our cells is quite well understood, and HIV combatant drugs are based on this (typically a concoction of three drugs are given that are specific to three points in the HIV cycle). However, given that HIV affixes its own genetic information into your DNA, killing off all traces in the body is impossible at this stage. All we can really do is control its spread. To add salt to the wound, the side effects of HIV therapy are tantamount to chemotherapy... very horrendous, as if the condition was not bad enough. AIDS is the term used to describe the condition of long term HIV damage. Sorry for the rant, I just find virology interesting.