Since February of last year, the avian flu has led to the deaths of tens of millions of farm-raised birds in the U.S., the deadliest outbreak on record. WSJ’s Patrick Thomas on how the egg industry is getting slammed and what companies are doing to try to save their flocks.   Further Reading: - America Is Losing the ‘Epic Battle’ Against Bird Flu  Learn more about your ad choices. Visit megaphone.fm/adchoices