WHITEHOUSE STATION, N.J. (AP) — Drugmaker Merck & Co. is considering selling some of its veterinary medicine assets or the animal health business of Schering-Plough Corp., as it prepares to acquire its New Jersey neighbor.

Merck executives said as much when they announced the $41.1 billion deal on March 9. As the two companies move closer to the deal's expected fourth-quarter closing, they are exploring their options for divesting either business, Merck spokeswoman Amy Rose said Wednesday.

"There haven't been any decisions at this point," she said.

Whitehouse Station, N.J.-based Merck has a 50-50 partnership with France's Sanofi-Aventis SA in a business called Merial. It sells some popular pet medicines — flea-and-tick blocker Frontline and chewable heartworm preventer Heartgard — plus Ivomec, which kills parasites in hogs and cattle. The venture had $684 million in first-quarter sales.

Kenilworth, N.J.-based Schering-Plough sells more than 15 animal medicine products, including antibiotics, fertility treatments and a number of vaccines for livestock; de-worming treatments for multiple animals; vaccines and treatments for ear infections and diabetes for dogs and cats, and the HomeAgain pet recovery system. The unit had sales of $630 million in the first quarter.

"There are a number of factors that could influence an ultimate decision," Rose said.

Those include whether federal antitrust regulators might find there would be too much overlap in the two businesses, and whether any terms of Merck's joint venture agreement with Sanofi-Aventis could preclude competition from the Schering-Plough products.

Shares of Merck fell 11 cents to $27.59.

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