Cattle futures slump on suspected screwworm case in Texas - CME
Hog futures edge higher for a third straight session
4 June 2026
1 minute read
By: Chicago Mercantile Exchange (CME) feeder cattle futures slumped on Wednesday as a suspected case of the flesh-eating screwworm parasite was identified in South Texas, reported Reuters.
Most active August feeder cattle fell 5.80 cents, or 1.66%, to finish at 342.625 cents per pound.
August live cattle futures fell 1.8 cents to 237.85 cents per pound.
Samples from two calves on a cattle ranch in La Pryor, Texas were taken on Tuesday and sent for testing, according to Texas Representative Don McLaughlin, who said he had seen photos and videos of the animals.
A photo seen by Reuters, which McLaughlin said was one of those he also saw, shows multiple larvae resembling the screwworm inside a bloody circular wound on an animal.
Screwworms are parasitic flies whose females lay eggs in wounds of any warm-blooded animal. Once the eggs hatch, hundreds of screwworm larvae use their sharp mouths to burrow through living flesh, eventually killing their host if left untreated. An outbreak of screwworm in the US could cause $1.8 billion in damage to Texas' economy alone.
Market players believe screwworm infestation in the US could reduce demand for beef from consumers nervous about the flesh-eating pest, but would be bullish in the long term by reducing the US cattle supply.
The uncertainty surrounding the news also drove futures down, said Arlan Suderman, chief commodities economist at StoneX, as market players watched to see reaction from commodity funds.
After the trading session ended, the US Department of Agriculture said the case was a "presumptive positive," on a briefing call, according to a source who took part in the briefing. The result means a preliminary test was positive but needs to be officially confirmed.
Meanwhile in hogs, most active July lean hog futures ticked up for a third trading session in a row, adding 0.35 cent to 102.000 cents per pound.
