foot long rats seem a tad big for a snake thats only 3-31/2 feet long.??
Even if it is a blood.
id be curious to see a size comparison pic of the snake and you or better yet the snake and rat
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i feed my snakes whatever is proportionate to there girth.
its a tough question to answer , as all rats come in different sizes and weights and my jumbos might be smaller then yours, significantly....etc..etc...
To answer your Q....
if the rats as big as it soundes and the snake is really only 3-3 1/2 feet...your probably feeding too much then you really have to...
its hard to say without a picture..
my thoughts anyways...