a1 Associate Professor, Department of Animal Science, and Coordinator of Research and Demonstration Farms, Iowa State University, Ames, IA 50011;
a2 Superintendent, Lauren Christian Swine Research and Demonstration Farm, Iowa State University, Atlantic, IA 50022.
At the Iowa State University Armstrong Research and Demonstration Farm in southwestern Iowa, a Swedish feeder pig production system was studied and demonstrated for 2-1/2 years. The system is based mainly on straw bedding, simple buildings, and intensive management. The system was designed to minimize pig stress and use of subtherapeutic antibiotics in the feed. Gestating and breeding sows were group-housed in a hooped structure with individual feeding stalls. Large round bales of cornstalks were used for bedding. Farrowing, lactation, and nursery phases were housed in a remodeled hog house. Cubicles with rollers and oat straw bedding were used for farrowing. Two groups of Yorkshire × Landrace sows bred to Hampshire boars produced feeder pigs in the system. Conception rates averaged 95%, and litter size averaged 11.3 live pigs/litter. Sows were allowed to select their own bedded farrowing cubicle. Prewean pig mortality, mostly from crushing, was high (29%), occurring primarily in the first 3 days. At 2 weeks of age the cubicles were removed and group lactation occurred. After group lactation the average pig weaning weight was 10.4 kg at 33.9 days of age. At weaning the sows were removed, and the pigs remained in the bedded farrowing/lactation room for 24 additional days. The pigs weighed 24.8 kg at 60 days of age, and overall nursery phase average daily weight gain was 549 g/day. Overall pig health was excellent with no major clinical diseases confirmed. The demonstration exceeded reproductive performance measures of typical small- and mid-sized Iowa farms.