US SMALL/MIDCAPS-Stocks higher for 5th straight day on earnings

NEW YORK Aug 9 (Reuters) - Mid- and smallcap stocks rose modestly on Thursday, putting smaller equities on track for their fifth consecutive advance, but gains were muted as the recent rally appeared to be losing steam.

Economic data showed number of Americans filing new claims for jobless benefits fell last week while the trade deficit in June was the smallest in 1-1/2 years, hopeful signs for the struggling economy.

A five-day streak would mark the longest run of gains for both the S&P MidCap 400 index and S&P SmallCap 600 indexes since early July, with the levels from the same period proving to be a resistance point before gains can be convincingly extended.

"The market has had quite a strong run in recent days and it wouldn't be unnatural for it to take a pause," said Lawrence Creatura, portfolio manager at Federated Clover Investment Advisors in Rochester, New York.

"Certainly there are a subset of stocks which are up because they deserve it; they just reported earnings and for many company earnings have been good."

Midcap Allscripts Healthcare Solutions Inc jumped 18.3 percent to $11.36 after the healthcare IT firm reported a quarterly profit below analysts' expectations, but gave a better-than-expected earnings forecast for the full year.

Fellow midcap Alliant Techsystems Inc reported a first-quarter profit above analysts' expectations on increased sales at its defense and sporting businesses, and raised its full-year forecast. Shares advanced 8.5 percent to $52.58.

The S&P MidCap 400 index gained 0.4 percent while the S&P SmallCap 600 index rose 0.3 percent. In comparison, the benchmark S&P 500 gained 0.2 percent.

Among smallcaps, Robbins & Myers Inc surged 27.2 percent to $59.51 after National Oilwell Varco Inc said it will acquire the energy equipment maker for $2.54 billion to expand its product line of well tools, pumps and valves.

Red Robin Gourmet Burgers Inc climbed 13.3 percent to $32.48 after the smallcap casual dining chain posted a second-quarter profit that beat Wall Street expectations.