Calabasas based staffing firm On Assignment Inc. reported a 29 percent increase in revenues over the same period a year ago, and a 54 percent increase in net income.

The company, which is expanding this year with the $600 million acquisition of Apex Systems, reported revenues of $167.1 million for the first quarter of 2012, up 29 percent from the same year-ago period. Revenues were up 3 percent from the fourth quarter of 2011.

On Assignment—which places professionals in information technology, engineering, life science and health care jobs—reported first quarter earnings of $5.4 million, or $0.14 per diluted share, compared with $3.5 million, or $0.09 per diluted share, in the first quarter of 2011. Excluding acquisition related expenses, net income was $6.8 million or 18 cents per diluted share for the first quarter of 2012.

“We had an excellent first quarter of 2012,” Peter Dameris, president and CEO, said in a prepared statement. “Each of our four operating segments generated double-digit revenue growth year-over-year. We also maintained strong gross margins and expense controls, such that our 29 percent revenue growth translated into 49 percent growth in Adjusted EBITDA and 100 percent growth in earnings per share when excluding acquisition expenses.”

Dameris said the company was looking forward to completing its acquisition of Apex Systems in the second quarter, which he said will create one of the largest professional staffing firms and the country, and the second-largest IT staffing firm, with pro forma 2011 revenues of $1.3 billion.

On Assignment said it anticipates second-quarter earnings to be in the range of $7.6 million to $8.2 million, and earnings per share of 20 to 22 cents.

Judy Temes