The Sow Gestation System Debate

For the last several years there has been ongoing debate regarding sow production systems and which of these represents the greatest potential for animal welfare. Now that the UEP and HSUS have entered into a voluntary agreement to address egg production systems it is very likely that the debate concerning sow systems will most likely move to the forefront.

The real debate is whether or not gestation crates should be allowed at all, not which alternative would satisfy most stakeholders in the debate. The only realistic alternative for the majority of the pork production in the US is a confinement group housed system. In certain geographic areas, there is potential for pasture-based systems; however, while these systems do have potential for specialized or niche market production, it is unlikely that those systems will replace the current standard of gestation crates anytime in the future. Consequently, the focus of this discussion will be the history of confinement systems including the development of the gestation crate production method and the primary alternative to that system, which is a group housed confinement system.

Among the most vocal activists, gestation crates are inherently cruel because while a sow can lie down, stand up and take one step forward and backwards, they do restrict freedom of movement. In a gestation crate system, social interaction is limited to audible interaction as the primary purpose of a gestation crate is to prevent sows from physical interaction. Many agriculture advocates believe that gestation crates are the most humane production system during gestation because, while freedom of movement is restricted (clearly a welfare detriment), the sows are protected from more aggressive sows and are guaranteed the proper nutritional plane because they are not directly competing for food. (The most aggressive sows get more feed than optimum for their own health and welfare and the least aggressive or weakest sows do not get adequate nutrition, and often risk getting very serious and sometimes lethal injuries particularly during feeding periods.) Most likely, like with most issues, the truth lies somewhere in the middle.

Gestation Crate System
Which system is more humane? The answer really depends on how you value each welfare attribute. Let’s look at the preeminent pork welfare expert in the world, Dr. John McGlone, and use his system to evaluate all sow gestation systems (gestation crate, confinement group housing, Dannish deep bedded system and a pasture-based system). If you place an equal value on each welfare attribute with a positive effect having a plus one value and a negative effect having a minus one value, essentially all of those systems are equally good (or poor). Only if you place a greater value on one particular welfare attribute (freedom of motion > proper nutrition or number of shoulder lesions) does one particular system have better welfare attributes than the others. While many activists believe that freedom of movement is so important that it dwarfs all other attributes, most animal science experts believe that the measurement of animal welfare must take into consideration all welfare attributes. In fact, Dr. McGlone states in a recent article that the debate about gestation crates is based on many factors including consumer perception, regulatory issues and other factors but that science does not support a move away from gestation crates.

Another frequent criticism of the gestation crate system is that it is primarily motivated by cost savings (or the greed of producers). While this is a convenient argument for some of our opponents, it is not really factually based. According the Dr. Lusk and Dr. Norwood of Oklahoma State University who have done some of the best consumer behavior work related to animal welfare to date, the cost increase associated with group housing systems compared to confinement systems is really inconsequential. While a move from battery cage systems to cage free egg production systems increased costs to the consumer by more than 21%, a change from gestation crates to group housing systems would only increase costs to the consumer by 1.7%. (Lusk/Norwood 2011).

Group housing

So if the issue of sow welfare is not based on science and unless you place higher values on certain welfare attributes than others all systems are welfare equivalents, why all the fuss and why do we have gestation crates in the first place? The answer really lies in an attempt by pork producers in the past to address a specific welfare problem in their group housing systems and meet a changing consumer preference. The timing of the introduction of gestation crate systems correlates very closely to the introduction of Pietran genetics in most commercial pork operations. At the time consumers were demanding a leaner, more muscular pork product. Pietrain genetics offered pork producers the ability to produce a leaner and more consistent pork product very efficiently especially in confinement production systems. Within a few years, Pietran genetics, largely unknown and unused in the US prior to this time dominated almost all commercial pork systems. While these genetics did accomplish the purpose they were intended for, they also brought with them serious issues for the pork industry that created even more problems including welfare issues. Pietran pigs are unusually aggressive compared to other more traditional breeds used in the US like Landrace, Hampshires and Durocs. Unbeknownst to most producers and even scientists at the time, they were also the principal carrier of the stress gene. This gene, most likely associated with their increased aggressiveness not only increased the propensity of sows housed in group systems to fight, which increased injuries, lesions and other welfare problems, the stress gene also can cause a “stressed” animal to literally fall over dead in its tracks.

The gestation crate system was an answer to resolve some of those welfare issues. Separating sows not only eliminated fighting and aggression, it also reduced the incidences of animals dying from stress from tasks as simple as walking down an alley. Over time, the stress gene and consequently much of the Peitrain influence has been eliminated from our production systems. Many animal welfare experts agree that a group housing system could not only be cost effective compared to gestation crates but that our genetics currently could be modified over time to produce the right type of animal that would perform in a group housed system without negatively impacting either welfare attributes or cost competitiveness. So why the resistance to change?

The answer to that from both sides is really quite simple and is not often discussed in this debate. For both sides, the issue is rooted in money, economics and each stakeholders own personal perceptions of what constitutes the best animal welfare. For a pork producer, they have to realize a return on their existing investment and they have a vested interest in maintaining the least stressful environment for their animals.  Many producers believe that a gestation crate system affords the animal the best balance of welfare attributes even though it restricts their movement.  For many of the activist organizations, this issue is as much a method of gaining public exposure for their own organization and raising funds as it is about improving animal welfare.  Those organizations believe that if you restrict an animals movement, there are no other welfare attributes that could compensate for this loss of liberty.  A modern pork production barn generally has a useful life of between fifteen and twenty years. Almost all of the costs of those barns are an upfront cost and really only work if the barn is utilized for its useful life. Retrofitting of these barns is not only expensive, it would require both a transition to different pork genetics and likely a lapse in production capacity which would result in a loss of income that many smaller independent and contract producers simply could not afford. There are virtually no new barns being built today that are gestation crate based systems. Given the current publicity and movements towards banning these systems by some activist organizations, it would make little economic sense to build a brand new gestation crate barn today. As older barns live out their useful lives and are being rebuilt or retrofitted, it is likely that the overwhelming majority of those barns will in fact be group housing systems.

It is important to remember that this debate is being driven not by science, or even better animal welfare for that matter but by consumer perception. The science in the matter is anything but clear when it comes to which system is the most humane system. Animal welfare is in large part evaluated by stress, or lack of stress in certain situations. Some studies which concentrate on measuring cortisol levels seem to indicate that cortisol levels are increased in gestation crate systems relative to group housing systems over time. However, in studies comparing multiple welfare attributes in the first thirty days of introduction into either a gestation crate system or a group housing system, the gestation crate system shows several advantages including fewer scrapes and lesions and higher pregnancy rates (an indication of better sow contentment) while other factors including incidences of lameness, weight gain and stereotypical behaviors (bar biting, sham chewing) were similar for both groups. Similar comparisons can be made over long term studies. Several producers whom I personally trust and who I know place animal welfare at the top of their priorities tell me that in their personal opinion, the gestation crate system gives the best balance of all welfare attributes of any system they have ever used. Since several of these have been in pork production for more than fifty years and have seen all of the systems, it is very difficult for me to discount their opinion especially since I personally know that their motivation is definitely not their own financial gain. Nonetheless, regardless of the reason, consumer preference highly favors any system other than gestation crates and consequently pork producers may be forced into changes even if it is not in the best interest of their animals welfare.

We have let other organizations dictate this debate and they are winning the war of consumer perception.  Those of us in agriculture, especially those whose livelihoods depend on agriculture need to take control of the debate back, not by trying to convince consumers that they are wrong and gestation crates are right, but by explaining that over time there will likely be a complete transition away from gestation crates anyway. Many animal welfare experts and animal scientists have been evaluating what alternative system is the best long before HSUS and others entered into the fray. By the time that most of the housing systems are due for retrofitting, there may be a completely new system that combines the advantages of both group housing and gestation crates.  Going the route of the UEP and authoring federal legislation is dangerous in my opinion by mandating systems that may not meet the demands of customers either and possibly preventing development and implementation of new systems that might be developed in the future.

If the National Pork Producers Council or other pork groups asked my opinion (they haven’t but I will give it anyway) I might make some suggestions to them. We can explain why gestation crates are perhaps the best balance of welfare and other alternatives all we want, but a large part of the public is simply not buying it. Since consumer perception in a large part of the country has already decided that gestation crates represent welfare impairments, instead of fighting those perceptions why not explain that currently due to the useful lives of these barns which represent a substantial investment there is literally no way to make a transition to new systems until those barns are retired or due for retrofitting.  Ballot initiatives are costly both in terms of trying to defend those practices but also in the consumer perceptions of agriculture in general.

If the NPPC and all major pork producers were to adapt a voluntary agreement that stated that they will be phasing out gestation crates over the next fifteen years, the overwhelming majority of those barns will have been rebuilt or retrofitted to group housing, freedom crates or some other system anyway. We will have taken back the debate and left the activist organizations standing on the sideline.  A bold move like this would not only allow us to recapture the debate with our consumers and be able to explain things like why gestation crates were a useful tool in the first place, it would leave those organizations trying to decide what their next fight will be.