Rayovac Corp. (ROV), which is diversifying beyond its battery business, on Tuesday agreed to buy fish and reptile supplies company Tetra Holding GmbH (search) from a private equity group for about $550 million, sending its shares soaring more than 9 percent.

The acquisition, which amounts to 415 million euros, comes on the heels of Rayovac's $536 million purchase of lawn, garden and pet products company United Industries Corp. Rayovac had said after that deal that it would look to buy more assets in the pet products industry.

"The acquisition of Tetra is a significant step forward in our strategy of becoming a more significant global player in the pet supplies industry," said David Jones, Rayovac's chairman and chief executive officer.

Tetra, based in Melle, Germany, was a highly sought-after acquisition target that makes food, aquarium products and accessories. It holds leading market positions in Germany, the United States, Japan and Great Britain. Tetra has about 700 employees and annual sales of about $266 million (200 million euros).

"The deal sounds expensive but we think this is a good acquisition for the company," Banc of America Securities analyst Joseph Norton said in a research note. "Rayovac is moving quickly into the pet care market and this acquisition strengthens the company's market position."

Shares of Rayovac soared 9.46 percent, or $3.89, to a new high of $45 after the deal was announced.

Rayovac said the deal should add slightly to earnings in the first year and expects it to close by June 30.

SunTrust Robinson Humphrey analyst William Chappel, Jr. said that because Rayovac will use most of its $600 million of credit to finance the deal, it was unlikely the active acquirer "will have the flexibility for other near-term deals."

Shares of Central Garden & Pet Co. (CENT), which some investors had speculated would buy Tetra, dipped slightly to $44, down 0.56 percent.

The principal shareholders selling Tetra are European private equity firm Triton, AXA Private Equity and Tetra management.

Citigroup Global Markets Inc. served as financial adviser to Rayovac on the deal. J.P. Morgan Securities Inc. served as financial adviser to the sellers.

($1=1.33 euros)