** Shares of a2 Milk Company ATM.NZ rise as much as 14.1% to NZ$7.510, their highest since August 16, 2024

** Dairy giant declares interim dividend of 8.5 NZ cents per share, its first

** Upgrades FY revenue growth forecast to low-to-mid double-digit percentage from prior forecast of mid-to-high single digit

** Reports half-year net profit after tax (NPAT) of NZ$91.7 million ($52.41 million), beating Visible Alpha consensus estimate of NZ$83 million

** Stock top gainer on benchmark index .NZ50

** Stock up ~19% YTD, including current session's moves

($1 = 1.7498 New Zealand dollars)

(Reporting by Manasi Dasa Sundeep in Bengaluru; Editing by Lisa Shumaker)

((Manasi.DasaSundeep@thomsonreuters.com;))