Devon Energy Corp on Nov. 3 reported a quarterly loss compared with a year-earlier profit, as low prices prompted the onshore U.S. oil and gas company to write down the value of some assets.

Crude oil prices have prompted shale companies like Devon to cut spending and costs, yet drilling efficiencies and improved well completion techniques are helping to push output higher in fields including the Permian Basin in west Texas.

Devon said it was raising its full-year production growth outlook for the second time this year.

"We are delivering this incremental production growth with significantly lower costs," Dave Hager, Devon's chief executive said in a statement. "We are now on pace to save around $1 billion of capital and operating costs in 2015 versus original expectations."

The Oklahoma City, Oklahoma company had a third-quarter loss of $3.5 billion, or $8.64 per share, compared with a profit of $1 billion, or $2.47 per share in the same period a year earlier.

Excluding one-time items including about $6 billion to write down the value of oil and gas properties, Devon had a profit of $316 million, or 76 cents per share.

Analysts on average had expected Devon to report a per-share profit of 52 cents, according to Thomson Reuters I/B/E/S.

Total oil and gas output was 680,000 barrels oil equivalent per day (boed), up 6 percent from the year-ago third quarter.

For the full year, Devon now expects oil and gas output to grow 8 percent to 10 percent, up from a prior forecast for growth of 5 percent to 10 percent.