Legal Question in Business Law in California

The answer to your initial direct question is "yes." Many professionals who have developed a professional reputation, clientele, etc., do not change their name professionally, even when they choose to take their spouse's name for their private and personal life. You do need to pick one or the other for all financial purposes, because it ties to your Social Security Number which can only be attached to one name. Your employer should pay you under whatever name you have tied to your SSN, which does not necessarily have to match the name you use professionally. The only tricky thing is your vet license. I have never dealt with this issue for a vet before, but I recently had a client who is a plastic surgeon with a similar issue. Her licensing agency allows her to practice medicine under any name as long as she obtains a fictitious name permit from her agency. This is separate from any fictitious business name filing requirements, though if you are an employee those would not apply to you anyway, only your employer unless and until you open your own practice.

A certified copy of your marriage certificate and your social security card or birth certificate should be all you need to get your name changed with the DMV and Social Security Admin. Check with your licensing agency for their requirements for using your old name after changing to your married name, and follow their procedures. After that, you should legally be able to use your married name for all financial purposes, either name in your veterinary work, and either name you choose for all other purposes.