Davies, whose career includes 79 tournament wins, was joined at the top of the leaderboard by Bath's Henrietta Zuel and Lydia Hall of Bridgend.
Davies shot seven birdies in her round despite suffering from an injured Achilles tendon which had prevented her from playing a practice round.
Davies told ladieseuropeantour.com: "It's a lovely golf course - I knew I liked it. Seven birdies and one bogey is a very satisfactory day."
Zuel also shot seven birdies and one bogey to stay in the hunt for her maiden Ladies European Tour title along with Hall.
Stacey Keating and Stacy Lee Bregman shared fourth place on five under, with Joanna Klatten, Beth Allen, Lee-Anne Pace and Carin Koch one stroke further behind, while 16-year-old English amateur Charley Hull was in a group on two-under.