The gestation-sow crate has lost favor in the United States, as it has in the European Union. 

In the EU, the crate was legislated out of existence on new farms in 2003 and on all farms by 2013. 

In the United States, it is consumer activism and market forces that have driven the animal-welfare issue, rather than legislation. The actions of Smithfield Foods, Maple Leaf Foods, Burger King and others tell us that consumer activism has led to strong market forces to ban the gestation-sow crate in the United States.

Isn’t it time that we admit that gestation-sow crates are a lost cause? 

Scientists and producers argue that sow productivity and welfare are essentially equivalent in well-managed pens and crates, so, therefore, the crate is acceptable. But this position cuts both ways. 

Sure, crates support the same welfare as pens, but pens are the same as crates, if both are well managed. This means that the crate is not a necessary production tool. If the science concludes that pens promote equivalent welfare, then we do not need the crate. Further, if selected consumers and stockholder activists object to the crate, then it is easy, in principle, to give up this technology for which a reasonable alternative is available (or so some people argue).

  Trickle-feeding delivers the same amount of feed as a drop system, but it is distributed slowly, allowing individual sows to get their full feed allotment with less competition.

The question for the U.S. pig industry is not if farms will convert from individual-sow to group-sow housing, but when the conversion will take place. 

So now we are faced with re-learning what constitutes a well-managed gestation pen.

Some research has been conducted in recent years in anticipation of this issue becoming real. We have learned some features of a well-managed pen, and this will help limit the damage done to sow welfare when sows are moved from the safety of an individual crate to a social pen. 

The advantages of the well-managed group pen are:

  • Less feed required in the winter;
  • Less penning materials;
  • Easier animal observations. 

The disadvantages of the pen are:

  • Body condition and subsequent reproduction can be more variable;
  • More space is needed in pens (compared to the crate) to prevent a drop in reproductive performance. 

Today we have genetic lines that were developed in crates (not in social groups), as well as a host of other technologies that were developed for individual housing. Most feeding and watering systems developed in the last 20 to 30 years were designed for individually housed sows. Most of our newer technologies were not developed for group-housed sows, simply because most sows were not group housed.

Taking the current genetic lines and technologies and simply moving them to a group pen will cause significant challenges —  for the producer and the pig.

Two recent studies have explored the development of pen systems and may help producers cope with this new challenge.

In a Texas Tech University study, gilts and sows (parity 1 and 2) were placed in gestation crates or in pens of four sows with about 17 square feet per sow. Within each housing system, sows were fed using a traditional drop-feeding system or a trickle-feeding system. The trickle-feeding system delivered the same quantity of feed as the drop system, but it did so slowly. This allows each sow a better chance of getting its full allotment of feed.

The reproductive performance for sows in pens and crates were statistically similar. However, when you look at the farrowing rate, you see that it is about 10 percent lower among penned sows than crated sows -- a potentially devastating economic impact.

In a University of Illinois study, pregnant sows were kept in breeding crates until 25 days after breeding. When confirmed pregnant, the sows were placed in a pen with 15, 25 or 35 square feet per sow or in a 14-square-foot crate. The penned groups were composed of five mixed-parity gilts and sows. They were fed on the floor in each pen.

Data in the second table indicate the rate of lesions for penned sows was much higher in the Illinois study than in the Texas Tech study. That is most likely due to the mixing of unfamiliar, multi-parity sows and floor feeding.  The study also shows that giving penned sows more space reduces skin lesions; how this relates to reproductive performance remains to be determined.

While there will be many lessons to come, those learned from these recent studies may shape the future of U.S. gestation-sow housing.

  • The first lesson is that, under sound management, sow productivity does not have to suffer in the move from crates to pens. However, understand that the variation in productivity is certainly going to increase. 
  • Second, sow welfare is not necessarily automatically better in a group pen than in a crate.
  • Third, the opportunity for significant risks to sow welfare due to injury is much greater in pen systems than in crate systems.
  • Finally, the most functional pen features regarding geometry, space allocation, flooring type, feeding system and suitable genetics are not known.

Accepting that the crate is a thing of the past should accelerate refinements in pen technologies in order to maintain productivity and acceptable sow welfare. Remaining in a state of denial that crates must go will only cause long-term economic and personal stress.

To discuss this or related topics with John McGlone, Texas Tech University, you may e-mail him at


The gestation-sow-crate issue is an example of how early adopters gain market advantages. Those that are committed to moving from gestation-sow crates to group pens will have preferred product purchasing from at least some buyers (Burger King, for example). After a while, when most sows are in group pens, this preferred-market-access advantage will go away. 

This basic business principle means that larger blocks of product can enjoy greater market access when they adopt animal-welfare related changes that the market views as positive.

Imagine how good life would be if it happened that on a given animal-welfare issue, the change actually improved pig welfare, improved productivity and gained customer favor. 

Now, anyone for banning castration?