Mrs Kempthorne and husband Robert own a 588ha dairy and dairy support operation near Te Anau.
They run 550 cows and 1600 ewes.
''I am delighted and really pleased [with the appointment] as I am passionate about the future of genetics in the dairy industry,'' Mrs Kempthorne said.
''I thought [going on the board] would be a good opportunity to be involved with something that is so important for dairy farmers.''
She has an agriculture degree from Massey University. Mrs Kempthorne and dairy farmer Scott Montgomerie, of Waikato, began their new roles on October 1.
However, she said it was ''early days yet'' as they had yet to attend their first board meeting, which would be held in December, and go through the induction process.
NZAEL is a subsidiary of DairyNZ, and manages the National Breeding Objective for New Zealand dairy cattle. It aims to develop, promote and deliver technologies that optimise genetic improvement in the national dairy herd.