pythagorean

I've been using Scivation Xtend, and recommending it to others. My original research led me to believe it's vegan, but someone recently told me that they source their BCAAs from feathers. At first I scoffed, but looked into it and their appears to be some controversy and a lack or clarification from Scivation. I emailed Scivation and politely asked what the source of their BCAAs. No response. That floored me. So now I'm skeptical. I see people heartily recommending Xtend here. Are you sure it's vegan?