ImproMed Inc., the world’s oldest veterinary practice-management software company, announced Friday that it has acquired its former competitor VETECH.

Ronald Detjen, president and CEO of ImproMed, based in Oshkosh, Wisc., said the company will maintain VETECH’s office in Walnut Creek, Calif., and continue to support the software indefinitely for its nearly 1,000 clients. He also said no employees will lose their jobs.

The acquisition of VETECH comes less than six months since ImproMed bought Sunpoint Software, Inc., of Windermere, Fla., which had just under 300 clients.

Detjen said the expansions of giants in the industry puts pressure on companies such as his to grow in likewise fashion. “Some of our competitors are part of billion-dollar corporations,” he said.

VCA Antech, one of the largest corporations in American veterinary medicine, for example, became the owner of VIA practice management software last year when it purchased Eklin Medical Systems Inc.

Detjen said merging with or acquiring companies is a necessary strategy for growth. “When you grow in an organic sense, one client at at time, that’s good but it’s very expensive,” he said.

He added that ImproMed intends to stick to its focus of veterinary practice software.

The privately held company was founded in 1979. Detjen said ImproMed had about 4,000 clients before it absorbed VETECH and Sunpoint. He declined to say how much the company paid for the acquisitions.