Bush, Eric J. - United States Department of Agriculture, National … - 1995
production states, accounting for nearly 91 percent of the U.S. hog inventory and nearly three fourths of U.S. pork producers. By … percent of pigs contained, total confinement facilities were the most widely utilized. The most widespread production phase … deaths were due to respiratory problems. The mean number of piglets born per litter was approximately 10, with 93 percent …