CHICAGO (CNN) - Prices of cattle futures -- a key component of the nation's $40 billion a year beef industry -- are plummeting following the discovery of a cow with mad cow disease in Washington state, and analysts expect meat prices at grocery stores around the country to drop as a result.

Several analysts who follow livestock trading said that in two to four weeks, U.S. shoppers may see some substantial savings.

CNNfn's Ceci Rodgers reports on mad cow scare and the pressures on cattle prices. Play video (Real or Windows Media)

At the Chicago Mercantile Exchange -- the centralized home of cattle futures trading -- prices fell 5 cents at opening Monday to 81 cents a pound, the full amount the exchange allowed prices to drop.

The CME changed the rules Friday, which previously allowed a drop of only 3 cents in a single day.

On the last two days of trading -- Wednesday and Friday of last week, since the market was closed for Christmas day -- prices fell 4-1/2 cents

The trading of live cattle, rather than futures contracts, is not centralized and can drop any amount. Analysts report prices on live cattle have dropped 12 to 14 cents since last week, falling to about 80 cents a pound.

The drop in live cattle future prices is attributed exclusively to the concerns over mad cow disease. Prices had been at record highs in early December, which analysts attributed to a ban on Canadian imports and soaring demand from Americans on high-protein diets.

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Despite the drop in futures prices, it is not yet clear whether demand by U.S. consumers for beef has dropped as a result of the mad cow scare. Three of the nation's largest fast food chains, McDonald's (MCD: Research, Estimates), Burger King, and Wendy's (WEN: Research, Estimates), said they have seen no drop in demand.

Greg Sherry, co-owner of Old Homestead Steak House in New York, said the drop in futures prices hurts cattle ranchers but bodes well for proprietors and consumers. "We should see a nice drop-off on the price of meat -- between 15 to 20 percent," he said.

Analysts were optimistic Monday that futures prices may pick up soon, particularly following news over the weekend that the infected cow came from Canada. Since futures trading involves only cows within the United States, analysts said the news may alleviate concerns and could help pave the way for prices to pick up in the coming days.  

--CNN Correspondent Ceci Rodgers and Assignment Manager Gene Bloch contributed to this report.