(Bend, OR)  --  A fourth case of bird flu is causing the poultry quarantine to expand in Deschutes [[deh-SHOOTS]] County.  The Oregon Department of Agriculture says the virus has been detected in a non-commercial flock of 40 chickens and ducks.  The quarantine of all poultry animals now stretches halfway through Redmond and that includes the fairgrounds where the Deschutes County Fair and Rodeo starts August 3rd.  ODA is working with 4-H on a plan that will allow participants to exhibit and sell market birds, but a show for breeding birds has been canceled.