巴西农业部长：在商业养殖场发生禽流感疫情后，我们已经度过了28天观察期的一半。我们希望在观察期结束后，显著减少贸易限制。

Core Viewpoint - The Brazilian Minister of Agriculture indicates that after an outbreak of avian influenza in commercial farms, the country has passed half of the 28-day observation period and hopes to significantly reduce trade restrictions once the observation period concludes [1] Group 1 - The outbreak of avian influenza occurred in commercial farms in Brazil [1] - The observation period set for monitoring the situation is 28 days [1] - The Brazilian government is optimistic about reducing trade restrictions after the observation period ends [1]