>There is something that prevents us of eating a dachshund, hamster,
spider.

I doubt very much it's because of anything innate. The dachsund is fairly
safe because of the partnership of man/dogs in the west. The others,
including rats, would not offer enough nutrition to sustain anyone for very
long (except in emergency situations). Have you ever reied eating a Cornish
game hen? They are no doubt delicious, but I find myself hungrier after
eating one because of all the work you have to do to get very little meat
:)