Given the circumstances, I think the photos are very good. I think clayne's idea of shared space would be a challenge indeed, not least because vets tend to have animals' lives as their priority, rather than 'sharing their space' with photographers. That said, I think you could try to develop some characterisation of the workers by shooting them in their breaks, as they arrive and leave work, you may be able to get some nice studies of them outside of their 'vet' role in that way.