By Debora Ely and Ana Mano MONTENEGRO, Brazil (Reuters) -Brazilian authorities hope to determine by Tuesday whether a confirmed outbreak of highly pathogenic avian influenza among wild birds in a zoo in the southern state of Rio Grande do Sul is connected with the country's first bird flu case on a commercial poultry farm in the same state,

A devastating U.S. bird flu outbreak and wider trade tensions with Washington have limited Chinese appetite for American poultry. China now blocks poultry from more than 40 U.S. states over bird flu, according to U.S. government data.

SAO PAULO — Brazil, the world's largest chicken exporter, ruled out three of seven suspected cases of highly pathogenic avian influenza, commonly known as bird flu, officials told a press conference on Monday (May 19),