Discovery Communications shares are gaining on Thursday after the educational network reported strength in its international markets. Over its June-ended second quarter, the company earned an adjusted $1.03 a share, 8 cents a share higher than analysts estimated. Revenue of $1.61 billion jumped 10% year over year and beat expectations of $1.59 billion. The TLC and Animal Planet network recorded a 23% jump in advertising on international networks, while domestic network advertising revenue increased 5%. However, the company lowered its high-end target for full-year revenue by $100 million to $6.53 billion. TheStreet's Keris Lahiff reports from New York.