5/12/2021 By Nayara Figueiredo and Roberto Samora SAO PAULO, May 12 (Reuters) - Dry weather and poorly timed planting are weighing on Brazil s second corn crop this year, reviving fears of another surge in feed prices like the one that battered big meatpackers after a 2016 drought. Soaring prices convinced Brazilian farmers to plant their second corn crop outside the ideal climate window this year. But the crop was hit by the country s worst drought in five years, reducing yields. Given surging demand in global grains markets, a corn shortage could squeeze profit margins in Brazil for some of the world s biggest protein producers, including JBS SA and BRF SA.