Aventis said they are combining their animal-healthcare businesses to create one of the biggest in the world. The combined business will have about a 29 percent market share in a global market worth about $19 billion. Merck shares fell. The broader S&P 500 index rose 1.94, or 0.2 percent, to 1,140.44. The technology-heavy Nasdaq composite index rose 8.47, or 0.4 percent, to 2,340.68. Cisco Systems said it is introducing a new internet router that will power the most heavily-trafficked parts of the web at 12 times the speed of its closest competitor. Shares of Cisco were little changed on the news, but the stock was heavily traded, with over 150 million shares changing hands. The New York Stock Exchange composite index rose 1.49 to 7,294.02. The American Stock Exchange composite index fell 14.22 to 1,902.68. And the Russell 2000 index rose 2.52 to 669.63.
