The law against eating meat and milk includes fowl as well although it is Rabbinical and not mandated from the Torah. Even so, there are similarities between fowl and cattle that do not exist, for example, between fish and cattle. The most important being that fowl were ritually slaughtered in the same way as cattle. It is certainly possible to make mistakes about meat and fowl. Certain parts of the turkey are extremely red and look like meat, some veal is pink enough to pass as fowl. Just those two cases alone are enough to warrant the stringency that the Rabbis introduced.
