* A2 Milk lifts annual revenue forecast by NZ$20 mln
* Shares up 7 pct on Friday, have risen 70 pct this year
* Company benefiting from strong brand recognition in China
* Rivals have had to overhaul China sales strategies (Adds details, updates share movement)
June 16 (Reuters) - New Zealand's a2 Milk Company Ltd raised its full-year group revenue forecast on Friday, helped by continued strong demand for its infant formula, sending its shares up more than 7 percent.
Group revenue is now forecast to be around NZ$545 million ($393 million) for the full year, an increase from the NZ$525 million it forecast in April, the dairy company said in a statement.
A2 has seen its share price climb more than 70 percent this year, due in part to its close relationship with informal travelling shopping agents known as "daigou", who send or carry its products to China.
In contrast, rival infant formula maker Bellamy's and vitamins manufacturer Blackmores Ltd have had to overhaul their China sales strategies after a period of weak sales.
A2 Milk has lifted its online brand recognition among Chinese parents to over 40 percent, double that of rival Bellamy's, according to a February report by UBS.
The company's shares were trading 7.6 percent higher at NZ$3.83 in morning trade. ($1 = 1.3875 New Zealand dollars)
Reporting by Sandhya Sampath in Bengaluru; Editing by Jane Wardell and Edwina Gibbs