Hog prices are rising for the fourth straight week as a swine virus threatens to crimp the supply of pork.

The price of hog futures for April delivery rose 0.6 cents, or 0.5 percent, to $1.13 a pound on Friday. The price has climbed 6 percent this week and is up about a third since the start of the year.

In other trading of commodities products, wheat and soybeans rose. Corn fell.

Most metals fell. Copper plunged on concerns about the health of the Chinese economy.

Gold, silver and platinum all fell. Palladium edged higher.

In energy trading, the price of oil rose $1.02, or 1 percent, to $102.58 a barrel.