I agree that the original post is confusing. You don't know what your college GPA is going to be until you get into college and start doing the work. A 3.1 is low, especially when you are competing for veterinary school. It is NOT a realistic goal to get straight Bs in community college courses and to expect to be a competitive applicant for a graduate school of any kind. You don't have to be a super genius to get As in college, you just have to be a dedicated student that spend time focusing on your coursework. The students that I have encountered that complain about being unable to do well in classes, they do not spend as much time preparing for exams as I did. You have to have a positive attitude, lots of organization, and you have to put in the time. If you are struggling in a course, that means you need to put in extra time. My advice has always been to get ahead in the course right away. Aim for a high A on the first assignments and exam because for almost every course the first material is the easiest to understand, and if you get that A you have some leeway with the later exams in the course. You will also do better on final exams if you do well on the exams throughout the course. Community college courses, from my experience, often have a lower level of expectations compared to courses taught at liberal arts colleges and top universities. Take your generals (English courses, intro math courses, speech class, etc.) through a community college to save money, definitely a wise decision that will not affect your acceptance into a graduate program such as veterinary school. You absolutely have to get mostly As in these generals, though, no matter what college or university you take them at. While it is true that science courses are weighted differently on applications, they definitely still look at your generals and they look down upon students with Bs and Cs in their generals.
I'm not sure I can agree with all of this advice. I never like replying with a rude tone, but I have to speak up.

1. Have you ever taken a class where the final exam was 50%+ of the final grade? Acing the first exams is always great, but the final makes or breaks you.
2. Please tone down the arrogance. I'm willing to bet you don't actually know how much time your friends spent preparing for exams unless you lived with them. When I hear people say exactly what you did, I have to laugh. Perhaps the mom with full time job and kids sitting in the seat next to you who is struggling won't be offended. Or the student with several jobs because they don't qualify for food stamps and are driving everywhere, spending gas money, volunteering for vet experience.
3. Not always true that acing the semester exams will lead to a better final exam grade. It is not wise to suggest getting comfortable after an initial good grade because it will give you "leeway."
4. B's ARE good grades. That's a 3.5ish at my school, which is an A/B to VMCAS. Granted, each school grades differently.
5. Not every school even cares about general education courses at this point. Michigan has dropped cumulative GPA's from consideration and is focusing on science and last 45. So unless you take all of your gen-eds in your last 45 (which I should have done...), it wouldn't matter what you got. So, OP, research your schools when that time comes to see if you need to play the game different than others.
6. Also, my CC courses were actually very difficult and I learned more in those chem courses than I did in my 4-year university chem courses. Because the professor actually cared about teaching, not just maintaining good standing with a university to continue his research.
OP: Repeating what others have said, but no, it shouldn't harm your chances. I think all schools require your upper level (300-400 level) science classes to be at a 4-year school, but those are usually after your first two years are done anyways.
That's fair. I'm sure there were other parts lacking, but from what I was told the B in the science class at a CC was indeed a reason they had mentioned for denying her acceptance. Not saying it's set in stone, just saying.
Sometimes the person giving you your file review really doesn't have a clue why you were denied and picks out the first thing that they see as a possible reason. I had a file review where I was told "I don't see any red flags here from the admissions committee....maybe it was because _______________?" I had asked for the top reasons why I was denied.