What program did the artist use to make this?

Never did get the crazy big boobs fetish. :/

Personally I'd say by page 4 panel 2 they are large enough, maybe a bit too big?

Base +6, gongon12 -6

Appears to be Blender or Autodesk Maya from the render settings.

Base +6, 1qazqaz +6

Nice Futurama reference on the first page

Base +6

@IronHide77777, @danund81,
according on tags from author's FurAffinity posts, it is Blender (rendered with Cycles).

Base +7