Firstly, nobody is saying there is no difference, but I am saying that humans and nonhumans both warrant equal moral consideration.
Secondly, how do you draw a line between humans and animals when humans ARE animals. Do you base your discrimination on any particular characteristic or just on the fact that they're not the same as you?
As for foetuses, are you saying dogs, pigs, chimps, etc. are not sentient? Are you seriously claiming that they have no more awareness than a bunch of cells?