A virus that killed millions of baby pigs in the last year and led to higher pork prices has waned thanks to warmer weather and farmers’ efforts to sterilize their operations. And as pigs’ numbers increase, sticker shock on things like bacon should ease. Already, hog supplies are on the rise, with 5.46 million baby pigs born between June and August in Iowa, the nation’s leading producer—the highest quarterly total in 20 years and a record 10.7 surviving pigs per litter, according to a U.S. Department of Agriculture report. It’s a significant turnaround from a year ago when the porcine...