Harvard Bioscience Inc. managed a neat trick during the first quarter, posting a major boost in net income even as sales slid 13 percent.

The Holliston laboratory instruments maker’s first-quarter sales fell to $19.1 million, compared with $22 million during the same period last year. But net income soared to $1.8 million, compared with $687,000 during the first quarter of 2008 — a 168 percent increase.

CEO Chane Graziano said the company’s long-term goal is to double sales and profits over the next three to five years by focusing on streamlining operations, introducing new products and hitting the acquisitions trail.

Harvard Bioscience made up a lot of ground by moving its British Scie-Plas business, shuttering the subsidiary’s fabrication operation and streamlining its operations. It spent $55,000 on the Scie-Plas restructuring during the quarter.

Last year, the company spent $1.8 million consolidating its electrophoresis subsidiary Hoefer’s administrative and marketing operations from San Francisco to Holliston and moving its Asys Hitech subsidiary from Austria to its Biochrom facility in Cambridge, U.K.

Those moves followed the 2007 sale of the Genomic Solutions and MAIA Scientific divisions to Digilab Inc. and the divestiture of HBIO’s Union Biometrica subsidiary last year.

All that restructuring led to higher gross margins and lower operating expenses during the 2009 first quarter. Harvard Bioscience’s $9.4 million in gross profit was 49.3 percent of total sales for the quarter, compared with 47 percent for the same period last year. Operating expenses fell to 37 percent of total sales ($7.1 million), compared with 40 percent during the 2008 first quarter.

Graziano said the company expects to post up to $85 million in sales for the full year and up to $19.5 million for the second quarter.