Kind of worried about euthanasia and being a vet tech?

I've done wildlife rehab for a long time so I'm used to euthanasia and death... if it's to end suffering, I can do it myself and I have before. However... I'm starting a vet tech job in a few days, and I'm worried about one thing. Will I be required to assist in the euthanasia of healthy animals that just aren't wanted anymore? Will I be required to assist in abortions? If I prove myself to be a fantastic vet tech but I don't want to assist with something I find morally appalling (there are 20 techs on the team so it's not like I'm the only one), am I going to get fired?