Why do huskies have so much vitamin A in their livers?

Seals have high vitamin A in their livers as vitamin A aids in the growth of their pups, which is important in the short summers of the Arctic in order to prepare for the harsh Arctic winter. Polar bears also have high vitamin A, mainly due to their diet of seals but possibly also due to the same need for fast growing offspring. Huskies are the dogs of eskimos who live in freezing conditions and hunt mainly seals and do not consume seal livers due to the lethal concentrations of vitamin A. We can see evidence of these evolutionary pressures on Huskies to develop the same adaption. We can also speculate that the gene determining how much vitamin A is produced is simple, possibly something that can change between the time dogs were first domesticated and the Huskies of today. The speculations I have made are not for certain but hopefully the evidence can shed light on the situation.