You can disenchant it. From what you said though, do you mean that the effect is always a static 3 points?
No the points of damage is tied into your enchanting skill, ie. the better at enchanting you are the higher the enchant damage will be, I have a bow with it and it's doing 40 points extra damage to animals.
That axe is the only one that has this enchantment.
Also, 3 points of extra damage to animals does not seem like it would be of any benefit in a dragon fight, if it even applies.
Not true, there is a cave that's the home to a troll and it's guarding a bow with the title of " the hunters bow" or something along that line.( the cave is around the Rifton area, that's all I'm sayen

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