I might have been unclear in my previous post. I referred to them as digits since cows don't have fingers. The humanoid equivalent would be fingers, and taurens should have fingers.
In the back of and just a little above the hooves are two little stumps, those are the other two digits.
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That is true, but Blizzard did try to have a 1:1 representation with the inclusion of the hump and debate on number of fingers. This is not a case of whether or not taurens should have a hump to accurately represent their real life inspiration, but how that representation is pulled off.