U.S. Poultry Farms Defend Against Bird Flu

A barbed wire fence is shown separating chicken egg laying facilities at the J.S. West Milling Co. egg laying plant in Hilmar, Calif. in this April 12, 2006 file photo. Only half of Americans are confident their government will deal effectively with the bird flu if it reaches the U.S., and they want strong steps including human quarantine and closed schools if there's an outbreak in the population, according to a AP-Ipsos survey. (AP Photo/Ben Margot, Files) (Ben Margot - AP)

Today, all trucks entering and exiting Silva's complex get an automated bath of ammonia-based disinfectant. Incoming drivers are asked where they've been and whether they've been exposed to poultry.

Every employee enters the site through a "dirty door" into a trailer that serves as a changing room. They swap their street clothes for pre-washed boots, hats and coveralls, then enter the hen houses through a "clean door." They reverse the process on the way out.

Various poultry companies even try to avoid each other on the road. They plot routes and stagger deliveries throughout the day, on the premise that the virus might jump from truck to truck.

The big rigs that rumble through the Central Valley most often bear the colorful logo of Foster Farms, which supplies dinner chickens primarily to California, Oregon and Washington consumers.

Foster Farms is taking a different approach with its "broiler"-raising farms. One of its facilities, the 120-acre Gurr Ranch, is not ringed by razor wire or even fencing. The hen houses are padlocked, and outsiders are not welcome, but the real emphasis is on making the ranch as repulsive as possible to migrating birds.

The resulting landscape looks like a moon base, intentionally devoid of trees and ponds but colonized by 64 identical outbuildings that house nearly 1.3 million chickens.

Migrating birds are looking for food, water and shelter, said Charles Corsiglia, an avian veterinarian on the staff of Livingston, Calif.-based Foster Farms, the biggest poultry company in the West.

"If we make our farms so that they don't have those things as they're flying over, they say, 'You know, that looks like a really bad place to land, because there's nowhere for me to waddle around,'" Corsiglia said. "'So I'm going to land at the dairy, or the canal.'"

Like the J.S. West Milling facility, the farm buildings are meant to be impenetrable by outside birds, though swallows flitted in and out of the eaves one recent morning. Corsiglia said these visitors can't get into the hen houses.

Every person must don disposable plastic boots before setting foot on the Gurr Ranch property. And truckers delivering feed are required to hose their rigs off with the same ammonia-based disinfectant used at J.S. West Milling.

It's all part of Corsiglia's three-part formula for biosecurity: isolating birds from disease, controlling people and equipment who come and go, and sanitizing everything.

"Animals that aren't exposed to disease don't get sick from those diseases," Corsiglia said. "The logic is so simple, it's laughable."