I called both airlines on your behalf and found out.
WestJet -
Contact WestJet and WestJet Vacations - Cargo, Charter and Head office info - 1-888-937-8538 No. I spoke with "Meechelle??" (might be Michelle)
There is only 1 dog per carrier and 1 dog per flyer allowed in the cabin.
Air Canada http://www.aircanada.com/en/customercare/index.html
No. I spoke with ..."Sheraya?" I don't know if I am spelling that correctly. Same rules as WestJet apply.
If more than just you is going on a flight, you can have 1 dog in a carrier at your feet and your companion(s) can also have a dog in a carrier, but no more than 1 per person. This is applicable for both airlines.