VCA Antech Inc. said its first-quarter net income was a little lower than expected as rising costs offset higher revenue from the company’s acquisitions over the past year.

After Monday’s market close, the Los Angeles veterinary hospital and lab operator reported net income of $31.9 million (37 cents per share), compared with $32 million (37 cents) a year earlier. Revenue rose 5 percent to nearly $331 million.

Analysts surveyed by Thomson Reuters on average expected per-share profit of 38 cents on revenue of more than $322 million.

Animal hospital revenue in the first quarter rose 3.5 percent, driven by acquisitions made in the past 12 months. Direct costs rose 6 percent to nearly $245 million as the company assimilated its new facilities.

Chief Executive Bob Antin said the quarter’s revenue likely would have been better were it not for the record snowfall throughout the East Coast in February.

“As the economy continues to improve, we remain optimistic with respect to our results for the remainder of 2010,” Antin said.

Looking ahead, the company reaffirmed its full year 2010 guidance that it will earn between $1.60 and $1.68 per share on revenue between $1.39 billion and $1.42 billion. Analysts on average are expecting earnings of $1.64 a share on $1.39 billion in revenue.

Shares were up 6 cents, or less than 1 percent, to $28.43 in Tuesday midday trading on the Nasdaq.