Effects of weaning age on growing-pig costs and revenue in a multi-site production system

Materials and methods: In Trial One (2272 pigs), litters were weaned at 12, 15, 18, and 21 days of age. In Trial Two (3456 pigs), litters were weaned at 15, 16, 18, 19, 21, and 22 days of age and categorized into three treatments (15.5, 18.5, and 21.5 days of age). In Trial Two, pigs in each age group were fed one of two nursery feeding programs. Each trial was conducted as a randomized complete block design with four blocks of nursery and finishing sites. All pigs within each block were weaned from a 7300-head sow farm on the same day into the same nursery, with each block remaining intact through finishing. Costs and revenue were calculated for each pen and modeled to simulate situations of either limited or nonlimited finishing space.