Yes, if she holds the listed veterinary degree or a provincial licence, because the TN criterion is satisfied by either credential. The state licence governs when she may practise, not whether she is admissible as a TN professional.
Two rules, two authorities, one start date
The immigration regulation lists the veterinarian profession with an alternative credential: a D.V.M., D.M.V. or Doctor en Veterinaria degree, or a state or provincial licence. A Kent applicant with a Canadian D.V.M. meets that criterion without any U.S. board involvement. The state board's licence is a condition of practising veterinary medicine in that state, and the employer, not the immigration officer, is responsible for not assigning clinical work until it exists. What the officer will want to see is that the position is genuinely professional and prearranged, that the applicant is a Canadian citizen entering temporarily, and that she does not own or control the practice. Explain in the employer letter what she will do lawfully during the licensing gap, such as case review, continuing education or work under state-permitted supervision, so the offer does not read as a job she cannot yet perform.
Hypothetical example: a Canadian forest-products economist is offered a U.S. role analysing timber-price data for one named manufacturer. The first review matches the offer's actual economic analysis to the listed profession, then checks the degree and citizenship records. A generic title such as strategy lead settles nothing; the signed duty description and credential record do. If the employer expects sales management instead, the case needs a different analysis before travel.