You can, but it's a multi-step process.
The trick is to export your PPT to a PDF, then import that PDF into Illustrator and prepare your artwork as if you were prepping it for a normal animation—one layer for item you want to animate.
You'll have to do some experimentation when choosing the PDF settings, as I can't remember what I had to change when I did this, but I do recall making a few passes on exports before I found the correct settings. I think there might be two ways to export a PDF and I believe I did it through the Acrobat Export function (I think there's a button in one of the toolbars in PPT's ribbon). I also think the option I changed was in the last or second to last section of the PDF export, but unfortunately I'm not able to check right now.