This sow is forced to lie with her head on the trough
as the stall is too short.
In breeding, gestation and farrowing areas dimensions are just as important, particularly as sows and boars are getting larger. Selection for lean, fast growing pigs has resulted in a much larger mature body weight. This means that by the time a sow reaches about fourth parity she will be considerably bigger than a sow of 10 or 20 years ago. Consequently, stalls and crates should be longer and wider than we have been used to.

A 2.1m (7ft) farrowing crate, which used to be the standard, is now completely inadequate and at worst may lead to severe welfare problems with bigger sows. The 2.25m (7ft 6ins) crate now being used in most new barns will eventually have to be increased to 2.4m/8ft as is used in Europe. Again, when we talk about length we need to measure ‘available’ length which will depend on the design and height of both the trough and the rear bars.

Many other aspects of crate design are crucial to sow and piglet performance, in particular height of the bottom rails which affects teat accessibility, rear bar design (some cause vulva damage) and presence of bolts or sharp edges which may cause injury. Most of the problems experienced could be avoided by utilizing pig dimensions at the design stage.

Flooring is also a critical part of the farrowing pen and researchers at CRB in Scotland measured piglets feet and compared them with the dimensions of slatted floor panels used in the industry. Many of these led to injury and the CRB work was instrumental in defining standards for such floors leading to much better products.

Finally, consider the male of the species. Higher mature body weights for sows and boars means that many boar pens used for service do not allow good courtship behaviour and sometimes extreme difficulty in mounting. Minimum length of any side of the pen should be 2.5m (8ft 3ins) and ideally more to achieve an effective service.

If we are going to continue to improve the productivity and efficiency of pig production we will have to understand much better how to meet the pigs needs and yet, in many cases, existing knowledge, such as that shown above, is not being applied. Next time I’ll look at how we can improve pen design by taking pig behaviour into account.

First published by Alberta Pork in their Spring 2003 Western Hog Journal.

By Bernard Peet, BSc - June 2003