One of the first things people dislike is the tail. Most people see the nude tail and correlate it with snake's slithery body. While I can see the resemblance (long thin hairless being) I feel it is important to realize why the rat's tail is the way it is. The rat uses this tail in a prehensile fashion, as a fifth leg/hand to hold onto branches, ropes, bedding, food, for balance while they are running, as protective weaponry and also as a bonding mechanism. Watch two rats intertwine their tails, you get the idea.
Here's a good article about the effect of diet,specifically those rich in spinach and blueberries, both with high concentrations of antioxidents and on the learning capabilities of rats.
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