This is a bit more controversial, but some LA clinicians also probably don't want students who have zero interest in working with large animals. It can be hard to show that you aren't okay with being elbow deep in an animal, covered in poop, etc. They're there to teach those who want to learn as well as practice good medicine. Even just in our labs so far, there is a hint of frustration when the majority of students are only there because they have to be. I do feel bad/like I'm wasting their time, but we have to be there even if I have absolutely no interest in doing a rectal on a pissed off mare. Part of the reason that my school did away with tracking entirely is because our large animal track had more elective blocks. Students who wanted more externship time would take the LA track, despite having zero interest in large animals. Supposedly it was a point of frustration for the LA faculty. We still have core rotations we all have to take. Equine medicine, equine surgery (yeah, they're two separate blocks ), food animal management. Our anesthesia service also does both sides of the hospital so you get your LA anesthesia there (not sure if that's a universal thing for vet schools or not). We can't avoid large animals completely.