I ordered a "Thermal Bowl" heated pet bowl to use in my chicken house this winter so that the chickens' water won't freeze. I had planned on running an outdoor extension cord from the back porch to the chicken house--approximately 115 feet. The directions on the bowl say NOT to use with an extension cord. Is that just a caution that they put on every electrical appliance, or is it something I should really be concerned about? I had figured on putting the bowl INSIDE the chicken house, and making the connection to the extension cord right near the door. Wonder if the chickens will mess with it too much?