What breed is my cat???

My sister found a stray kitten in Alberta, Canada. It was starving and abandoned in the middle of nowhere. I'm sure it is a recognised breed of some kind and had been abandoned because he is polydactyl on all four paws (too many toes). Can anybody help me identify the breed? Many thanks, Ivan

He is a ...... Fluffy cat! 

Okay in all seriousness some more photos will be needed to give a better guess. Side body, standing, and maybe a full body from the front should do it. Need to be able to see body shape, tail, patterning and how he looks when he is not all scrunched up to get a feel for it.

From this photo I can say for sure a bicolor tabby as the color/coat pattern. Bicolor means a lot of white and it is usually in the face, down neck and over belly spot with white paws is common. The tabby patten is obvious but which specific pattern would be only known with the side view to see the full pattern. Long hair is also evident but I am not seeing any specifics to point to a certain breed. Which means Domestic Long Hair would be the breed which just means a long hair cat of non-determined breed. 

Polydactyl doesn't actually indicate a specific breed (fun nickname though is Hemingway cat). There are breeders who are trying to get an American Polydactyl as a recognized breed but to my knowledge it is still open for new cats to be registered into it. Which means it is still in development and doesn't really have a specific recognized guide to define the expected standards of the breed. What little I can find just says medium to large with all coat colors and types and more broad chested. Much like the Munchkin breed came out of a specific genetic quirk I can see it being a specific "breed" in many years. But the one thing with a breed from a mutation is that the mutation can be seen outside the breed too because it was naturally occurring before people decided to  bred for it. So having the feature does not always equal being the bred. You also tend to see several feral/strays/outdoor cats in the same area with the same mutation just from interbreeding. There are areas where you can find almost entire colony's with the shorter tails for example ever though they aren't a recognized purebred. 

Which brings me around to a general guess on this photo alone that there may be some Maine Coon somewhere in your cats past. Maine Coons have been known to show polydactyl more than other breeds and some breeders have tried to bred that trait into their lines more. Maine Coon is a naturally occurring North American breed (well as natural as you can get when colonist let their cats out and a population with specific traits started to develop in the new world when the European cats mixed with the native cats). The fluff and tabby pattern could indicate some Maine Coon somewhere in the lineage. Maine Coon descendants and mixes are fairly common because of how they developed and spread across the country. Any large fluffy cat in North America likely has links to those first cats of American colony history. A key factor would be how big your boy is because Maine Coons are large cats reaching (healthy, not the cats that are just overweight) weights in the teens or higher.