* Shares rise, after initially falling at open
* Q3 results came in below consensus forecasts
* But results showed strong trends at UMG and Canal+
* Vivendi shares up around 20 pct so far in 2017 (Releads with updated share price, adds analyst comments)
PARIS, Nov 17 (Reuters) - Vivendi's shares rose on Friday as strong trends at the media conglomerate's UMG music arm and Canal Plus unit helped to offset third-quarter results that missed analyst forecasts.
Vivendi shares initially fell 2.5 percent at the start of trading, but the stock then gradually recovered to stand 1.3 percent higher in early session trading, on the back of some positive analyst commentary after its results.
Vivendi, chaired by French billionaire Vincent Bollore , has built up stakes in Telecom Italia, MediaSet and video games group Ubisoft, and it bought advertiser Havas this year.
Its third-quarter EBITA (earnings before interest, tax and amortization) rose 5.7 percent from a year ago to 293 million euros ($345.4 million), while its revenue increased by 19.3 percent to 3.18 billion euros.
That fell short of a consensus of analysts polled by Inquiry Financial for Reuters, who forecast EBITA of 324 million euros.
However, Vivendi kept its 2017 outlook for higher revenues and profits, and said it expected revenues at its UMG music arm to grow by 10 percent at the end of the year.
"EBITA missed by 8 percent in 3Q, but new full-year guidance for UMG should be enough for small consensus upgrades and greater confidence in Canal Plus targets," Deutsche Bank analysts said in a note, keeping a "buy" rating on Vivendi.
For 2017, Vivendi expects revenue to increase more than 5 percent and EBITA to rise by around 25 percent, prior to its integration of the Havas business.
"We believe music offers the best content story in media and UMG more than underpins Vivendi's share price and has the potential to drive multiples of upside, as subscriptions drive revenue growth, margin expansion, a re-rating and ultimately re-leveraging," wrote JP Morgan, keeping an "overweight" rating on Vivendi.
Vivendi shares are up by around 20 percent in 2017, outperforming a 6 percent decline on the STOXX Europe Media & Publishing index.
($1 = 0.8482 euros) (Reporting by Sudip Kar-Gupta; Editing by Sarah White and Leigh Thomas)