Proto Labs, the Maple Plain- based contract manufacturer, saw profits and sales grow during the first quarter, but not enough to meet analysts’ expectations.

The stock fell $17.68, or 21.74 percent, on Thursday to close at $63.64.

The prototype maker and high-tech injection molding and milling company saw sales grow 24 percent to $72 million. Profits, however, grew just 2 percent to $10.66 million, or 40 cents a share, as results were hampered by a slowdown in the industrial sector, officials said.

Excluding foreign currency exchanges and other one-time factors, earnings were 44 cents a share, which is 2 cents below analysts’ consensus expectations. Sales also missed Wall Street’s consensus forecasts by about $2 million for the quarter that ended March 31.

Company officials noted the sales increases and how recent acquisitions contributed to the quarter.

“We continued to generate revenue growth in the quarter, driven by strong 3-D printing revenue, steady injection molding and [computer-controlled] machining growth and the contribution from [the recently purchased assets of] Alphaform AG,” said CEO Vicki Holt in a statement.

Alphaform contributed $4.9 million to Proto Labs’ sales during the quarter. Proto Labs bought Alphaform in October for an undisclosed price and instantly gained metal molding, laser sintering and 3-D printing operations in Germany, Finland and England.

“We continue to make good progress with our 3-D printing business,” Holt said. “We are in the process of moving into our new 3-D printing facility in North Carolina, and manufacturing there has begun.”

Proto Labs entered the 3-D printing business in April 2014 when it bought FineLine Prototyping in Raleigh, N.C., for $37 million. The company recently spent $25 million expanding its operations in Raleigh.