Wean to Finish Concept Attracting Attention

Mike Yacentiuk, Swine Specialist, Carmen, MB

A relatively new concept in pig production technology is generating a great deal of interest in various areas of North America.

The concept of wean to finish facilities within a two-site production system is not a novel notion, being successfully implemented and operated in the midwest United States and Manitoba for a number of years. The farrowing facilities of this system are identical to the structures that are commonly employed in traditional farrowing-only farms. However, the factor that makes the different variations of the wean to finish concept unique is the adaptation of technologies used in nursery and grower/finisher production systems into a combined unit.

Piglets enter the barn within a one week period at approximately 18-20 days of age (5 kilograms) directly from the farrowing facilities. The animals are sexed and double stocked (initially at 4 ft2) within finishing pens or a specialized nursery section of the barn. Double stocking in early generation units and finishing barns occurs in order to more efficiently utilize pen space. Before the pigs become crowded, at approximately 30 kilograms bodyweight, the groups are split and moved to another pen (initial stocking 8 ft2) within the same barn or moved to a separate barn for finishing.

Due to the piglets' young age, special consideration must be given to their well-being during the early stages of their growth. Although some producers have placed piglets directly into grow/finish facilities, modifications have occurred to the pens and the equipment within. For the first two weeks, rubber mats are placed in the pens to serve as a sleeping and feeding area. Supplemental zone heaters are also installed. Wet/dry feeders are not suitable for very young pigs and specialized dry feeders have generally been temporarily installed until the pigs reach a suitable size. Spaces within the pen partitions should be narrow enough to restrict pen-to-pen movement. Generally bowl-type waterers have been used until piglets are able to use existing bite-type drinkers.

To overcome some of the inadequacies of earlier versions, new generation wean-to-finish facilities are being constructed with pens and equipment catering to the needs of the young piglets. Some of the changes include a combination of heated concrete, steel or plastic flooring, as well as specialized waterers and feeders in the nursery section of the barn.

The latest generation wean-finish "Sandwich barns" have been further modified to better utilize space and hopefully reduce capital costs. Unlike the first generation wean/finish barns that double up pigs early in the nursery, these barns utilize dedicated nurseries attached to two grow- out units. The grow-out barns are connected by a walkway to either side of the central nursery. The nursery is rotated on an eight week cycle while the finisher barns are rotated on 16 week intervals for a total pig cycle of 24 weeks.

Proponents of this system state that maintaining pen integrity by eliminating mixing of pigs as well as decreasing the number of moves reduces stress and greatly improves herd health, reduces pig mortality and improves subsequent performance. In the first generation wean/finish system and traditional grow/finish barns, some mixing of pen mates does occur when the batches are split; however this is the trade-off for more efficient use of floor space. In the later generation system, it is possible to maintain pen integrity throughout the grow-out period. One of the keys to success in a system of this type is the use of single-source pigs.

Some typical performance values of a wean-to-finish barn for pigs from 5 to 115 kg are (US results): mortality of 3%, 160 days to market, daily gains of 650-700 grams and feed conversions of 2.5-2.6.

Other benefits of this system include less trucking of pigs, the potential elimination of a profit centre and the adaptation of this system to smaller producer networks. The single largest criticism of the Sandwich Barn concept is even though the barns are operated all-in all-out, the total complex is essentially a continuous flow barn with animals on site encompassing a wide range of ages. The major concern generated is a possible interruption of the production schedule by a disease outbreak and the corresponding financial cost to restore the system's pig flow.

As with any new technology, there is no doubt that further discussion about this concept will continue as the system evolves.