I used to eat a lot of pork. Whether it was bacon, chorizo, pepperoni, schnitzels, sausages, hotdogs, or pork chops, I loved it all. During my first trip to Korea, I ate a lot of Korean barbecue. It was always a fun experience to cook pork belly and chat with friends in a nice atmosphere. We went to the buffet so often that the owner allowed us to sit at the table for more than the ninety-minute time limit. At that time, I never really thought about the process of how that pork came to be. Of course, I knew that the pork came from pigs, but I never really thought about how the pigs were raised and killed. I saw pork as an object, not an animal’s body parts. Every year, the world consumes more and more pork. In 2021, the world slaughtered 1.4 billion pigs and consumed 120 million tons of pork.1
After learning about the process of raising and slaughtering pigs, I came to empathise with the pigs that I had eaten. I realised that they are not “just pigs” and are unique individuals who can suffer both physically and emotionally. Unfortunately, we do not receive much education about how the animal products we eat are produced. We may imagine the process of how pigs are raised and slaughtered, but this image may not match reality. In this post, I will describe this process. Before reading on, I want to provide some caution. In the following sections, I will describe some violent and cruel processes and show some related pictures. So, you may feel some uncomfortable emotions from seeing this content. Parents should decide whether to allow their children to read this content. However, if we want to make an informed decision about eating pork, an important step is to learn about how pork gets on our plates.
Sows
Some female piglets are selected for breeding purposes. To collect semen, boars are restrained and made to ejaculate into an artificial sow. Farm workers then artificially inseminate the sows.2 During pregnancy, sows are confined in small cages called gestation crates or sow stalls, for about 16 months.3 The picture below shows a sow in a gestation crate. Inside these small cages, the sows are unable to turn around or move freely, causing them to experience physical and psychological distress. Pigs are intelligent animals, however, inside these crates they cannot exhibit natural social behaviours or engage in normal activities like foraging for food. As a result, sows in gestation crates often become irritable and exhibit repetitive behaviours such as bar-biting. This is called stereotypic behaviour, and is common among confined animals.4 Physically, gestation crates cause the sows to develop lameness, weak muscles, and skin lesions from being forced to lie down for long periods of time.5
A pregnant sow inside a gestation crate. Farm Transparency Project.6
After giving birth to piglets, sows are confined in another small cage called a farrowing crate, for about 4 months.4 The farrowing crate has a small section for the sow and another section for the piglets. Sows and piglets are separated by metal bars. The photo below shows a farrowing crate. Piglets can easily access the sow’s teets from the adjacent section. However, because of their large size, sows may accidentally crush piglets when lying down. While the separated sections reduce the likelihood of piglet crushing, it still occurs.5 Of course, protecting piglets from being crushed is important, but we have artificially created the conditions that increase the risk of crushing. In nature, sows and piglets are not confined in cages and so the likelihood of crushing is much lower.
Sow and her piglets inside a farrowing crate. Farm Transparency Project.6
Sows endure this process for about two years and five pregnancies. As they age, sows tend to have fewer piglets, making it uneconomical for farmers to continue raising them. Consequently, sows are slaughtered at 2-3 years of age. Boars are typically killed at around 18 months old.7 In comparison, pigs can live up to 10-15 years in nature.8
Piglets
Piglets are separated from their mother and sent to a weaning pen, 3-4 weeks after birth. In nature, piglets would wean at around 5 months old.4 In order to prevent piglets attacking and cannibalising each other, the piglets tails are cut and their teeth are clipped. Furthermore, a portion of their ear is cut out in varying shapes to indicate their identity.9 Pigs do not naturally bite each other’s tails, but under factory farm conditions, they may do so out of frustration. Tail biting is a painful experience, both acutely and chronically. Even after tail docking, pigs may still try to bite the remaining parts of each other’s tails.10 Male piglets start producing hormones during puberty, which can cause their flesh to have an unpleasant smell and taste. Therefore, males that are not used for reproductive purposes are often slaughtered before puberty or castrated. Physical castration using a knife is a very painful and common practice in some countries, while in other countries male pigs are chemically castrated.4
After 8-10 weeks, the piglets are sent to a growing pen.9 The conditions in factory farms pose many problems for the welfare of the pigs. Pigs prefer to defecate and urinate outside of their living area, but they are forced to live directly on top of their waste due to the small area available per pig. This increases the risk of disease. Although waste can be removed through holes in the floor, it is not completely removed.11 The pigs also suffer from claw injuries, lack of opportunity to naturally forage for food, lack of space to make a nest, and being weaned too early, which causes irritability. When pigs are placed in a pen with other unfamiliar pigs, they experience stress. Additionally, pigs may develop ulcers from not consuming enough fiber.12
If the pigs are injured or do not grow quickly enough, the farmer may kill them on the farm, as it becomes economically unjustifiable to continue raising them. Young piglets can be killed by blunt force to the head. However, this can easily go wrong and there are cases where piglets need to be hit repeatedly.13 Older pigs are typically placed in a carbon dioxide gas chamber. When the carbon dioxide concentration in the chamber exceeds 20%, the pigs begin to scream and convulse wildly. The pigs try to escape from the chamber but cannot get out. It takes more than 2 minutes for the pigs to lose consciousness and up to 9 minutes to die.14 Euthanising injured or sick pigs could be perceived as an ethical decision. However, it is important to note that we have artificially created the conditions in which we are required to euthanise them. If pigs survive the rearing process, they will eventually be sent to the slaughterhouse at around 5-6 months old.15 Hence, most commercial pigs live only about 3-5% of their natural lifespan.8 The pigs that we eat may not look like cute piglets, but they are typically very young.
Transport
Pigs are typically transported from farms to slaughterhouses by truck, and sometimes these journeys can take more than 8 hours.16 The picture below shows pigs loaded into a truck for transportation to the slaughterhouse. To avoid contaminating their bodies with faeces during transport, employees do not feed the pigs for up to 12 hours before transportation. Additionally, the workers do not feed the pigs during transport. This makes it even more difficult for pigs to maintain their body temperature on cold days. On hot days pigs can easily become overheated, as they do not have the ability to sweat. If the truck stops frequently, overheating is more common. Furthermore, the pigs cannot drink water on the truck and cannot rest comfortably as they are packed tightly with other pigs. Prolonged transportation can lead to dehydration, fatigue, stress, and death.17
Pigs being transported to the slaughterhouse. Farm Transparency Project.6
Slaughterhouse
Unfamiliar pigs can become stressed and may attack each other when they meet before, during, and after transportation to the slaughterhouse. Typically, pigs also cannot eat food at the slaughterhouse. It takes up to 12 hours after their arrival to the slaughterhouse before they are finally given food. However, not all countries do this.17,18
Pigs are typically stunned before slaughter, either by electrocution or by exposure to carbon dioxide gas. The most common method is stunning with carbon dioxide, which is considered the most humane. There are other alternative stunning methods, however, they are considered too expensive or impractical. During carbon dioxide gas stunning, several pigs are forced into a cage and lowered into a chamber filled with carbon dioxide at a concentration of 80-95%. It takes 33-47 seconds for the pigs to become unconscious, however, this is not a peaceful process. Pigs struggle to breathe in the chamber, give off loud squeals, and experiencing stress, pain and involuntary muscle contractions. The carbon dioxide reacts with the water inside the pigs’ noses to form carbonic acid, which irritates their nasal membranes.19 The image below shows pigs in a carbon dioxide chamber. One study investigated whether pigs were averse to chambers filled with 90% carbon dioxide. The researchers deprived pigs of food for an extended period and placed an apple inside the chamber. The pigs put their heads into the chamber, briefly but quickly withdrew.20 This study demonstrated that pigs prefer to be hungry rather than enter the chamber.
Pigs being stunned in a chamber filled with carbon dioxide gas. Farm Transparency Project.6
Using electricity to stun pigs is less common, but is used in some small slaughterhouses. In this case, the pigs are restrained, and an electric current is passed through their brains. However, there is a higher chance of incomplete stunning the pigs using this method.
After being stunned, pigs are hung upside down and the slaughter worker stabs the pig’s throat and body with a knife. This process is also known as sticking. If the slaughter worker cuts the pig accurately, the pig’s blood pressure and the blood flow rate to the brain reduces quickly. The image below shows a pig being sticked. If pigs are stunned with carbon dioxide, they can wake up 15-30 seconds later. Therefore, if the slaughter worker does not cut the pig quickly enough or does not allow enough blood to flow, the pig can consciously experience this process. As blood flows, the pig’s muscles can convulse, and the pig may accidentally kick the slaughter worker.21 Afterward, the pig’s body is lowered into a hot bath, to make it easier to remove the pig’s hair.22 Finally, the pig’s body is butchered and processed into our favourite cuts of meat.
A pig being sticked with a knife. Farm Transparency Project.6
When these processes go wrong
The processes I described in this post are common and legal. The information came from research articles in the field of animal welfare, and from industry standards. Regulations and methods may vary by country, but the processes are similar. The processes I mentioned are the ideal procedures of the industry, but there are situations where things go wrong. In Australian abattoirs, there are many situations where animals are abused. For example, pigs repeatedly hit with metal bars on the head, killed with a sledgehammer, electrically stunned in the eyes or ears, or stabbed after being improperly stunned.23 Fortunately, these incidents were captured on video and the slaughterhouses involved were penalised, because these actions are illegal. However, outside of these examples, pigs experience abuse every day that goes unreported. Even if animals are not cruelly abused, the process itself is fundamentally exploitative. By demanding pork, we create the possibility of such incidents to occur, whether they were intentional or not. In fact, we can never truly know how the pigs we buy and eat were treated. Even if farmers and slaughterhouses follow the world’s highest standards, there will still always be issues related to animal welfare and animal rights. Of course, there are pig farms that are not factory farms. In these cases, pigs may be raised in a pasture. However, these farms are relatively rare. As there are various types of intensive farms, it is difficult to define factory farms precisely. Therefore, there is no official evaluation of the number pigs raised in factory farms. However, based on unofficial analyses using United Stated Department of Agriculture (USDA) data, it was concluded that approximately 98.3% of pigs in the United States are raised in factory farms.24,25 There are also farms with better-designed farrowing crates and those without gestation crates or farrowing crates altogether.15,26 However, are these methods absolutely ethical just because they are relatively better than others? No matter how pigs are raised, eventually the pigs will be sent to the slaughterhouse and experience the stunning and slaughter processes as described.
Conclusion and reflection
I described these processes in writing, but we cannot truly understand them until we see them for ourselves. The documentary Dominion shows the process of raising and slaughtering animals, primarily in Australia. However, other countries have similar animal welfare regulations to Australia. Some countries have better regulations, and some have worse regulations, but the basic processes are similar. You can see the described processes in this documentary from the 4-21 minute marks, which is available for free on YouTube. Although this documentary shows some extreme examples, in general it shows many common practices. Watching these scenes can be uncomfortable. However, if we want to make an informed choice about eating pork, seeing the process of how pigs become pork is the least we can do.
Reflecting on our actions, values, thoughts, and emotions is important. How did you feel while reading or watching this content? Why did you feel that way? Did you already know these processes? Or were you surprised? How would you feel if you were in their situation? Of course, humans and pigs are different, but pigs are intelligent, can suffer, and feel emotions. How would we feel if someone raised and slaughtered our pets like this? Through reflection, I realised that pork is not just a object and pigs are not “just pigs”. Pigs have personal and unique experiences. At this moment, as you are reading this sentence, pigs are enduring these processes. The pigs that we will be eating in a few weeks are being slaughtered as we speak. Every time we buy pork, we are voting with our money for pigs to have these experiences. Can we justify continuing to eat pork if we are in a position to live without it? Of course, the choice to eat pork also depends on a range of factors outside of animal welfare. There are also environmental, health, economic, psychological, and cultural aspects, which I will talk about in future posts. You can view my other posts to learn about how dairy and beef or chicken and eggs are produced.
References
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