Segregated Early Weaning (SEW) of Pasture-farrowed Pigs
Segregated early weaning (SEW) works well with pasture-farrowed pigs. The SEW pasture-farrowed pigs weighed about the same as conventionally weaned pigs at 9 weeks of age with lower death losses (about 2% less). For the period 5–9 weeks of age the SEW pigs gained more rapidly and were more efficient converting feed to live gain than pigs weaned at 5 weeks of age and moved to an open-front shelter. However, costs were presumably higher for the SEW pigs because of higher labor costs from multiple feedings per day, higher-priced pig feed for early weaned pigs, higher utility costs, and the added cost of a nursery unit. Based on the results of this trial, SEW is compatible with pasture farrowing. However, pasture farrowing may not be as compatible with the mechanics of SEW. For example, because pasture farrowing is seasonal, the SEW nursery may not be kept full at all times. This would reduce the throughput, the number of pigs through the unit, which would increase the fixed building costs per pig. A new approach of putting newly weaned 2-week-old, 10-lb pigs directly into a finishing unit would partially alleviate this situation or lower fixed cost SEW nurseries are needed that then could be used on a seasonal basis. On the other hand, the technique of early weaning pasture-farrowed pigs has the potential of extending the farrowing season while reducing piglet mortality and minimizing the negative effects of weather extremes. By its nature, a one-litter pasture-farrowing system may benefit less from SEW than other more intensive or continuous pig production systems. In a one-litter system considerable age segregation of pigs occurs on the farm at all times. The sows are sold after weaning. At most times throughout the year the pigs on the farm are the same age. If the herd already has a high health status, the advantages of SEW are much less. Therefore, SEW will work for pasture farrowed pigs but herd health status and overall SEW costs need to be carefully evaluated. A cost comparison of SEW for pasture-farrowed pigs is elsewhere in this report.