In commercial slaughter facilities, cows are killed through a two-step process: first they are stunned to render them unconscious, then they are bled out by cutting major blood vessels in the neck. The goal, required by U.S. federal law, is that the animal feels no pain during the process. Roughly 2.8 million beef cows were slaughtered in the United States in 2024 alone, with recent peak years like 2022 approaching 4 million head.
Stunning: How Unconsciousness Is Induced
Before anything else happens, the animal must be made unconscious. The Humane Methods of Slaughter Act requires that all cattle are “rendered insensible to pain” before being shackled, hoisted, or cut. Three main stunning methods are used for cattle, though one dominates the industry.
Captive Bolt Stunning
The most common method uses a device called a captive bolt gun, which is pressed firmly against the cow’s forehead. When triggered, it fires a metal bolt into the skull. A penetrating captive bolt works through both concussion and direct trauma to the brain tissue, causing immediate unconsciousness. The bolt enters the brain, destroys tissue, and retracts back into the device. It is not a traditional firearm and does not fire a free projectile.
Non-penetrating captive bolt guns also exist. These deliver a blunt impact to the skull that stuns through concussion alone, without the bolt entering the brain. Because they cause minimal brain tissue destruction and produce a less reliable loss of consciousness, they are generally reserved for smaller livestock like young pigs, not full-grown cattle.
Electrical Stunning
Electrical stunning works by passing a high-amperage current through the animal’s brain to trigger what is essentially an artificial seizure. In cattle, this is more complex than in smaller animals like pigs or sheep. A single current passed from the neck to the chest does not reliably produce unconsciousness in cattle, so a two-stage approach is used: a 1.5-amp current is first applied across the head, followed by a head-to-body current. When effective, the animal goes through a rigid phase followed by a kicking or paddling phase as the seizure progresses, both signs that the brain has been fully disrupted.
How Long Stunning Takes
With a properly applied captive bolt, unconsciousness is essentially instantaneous. Electrical stunning in cattle takes roughly 5 to 20 seconds to fully take effect, depending on the equipment and application. During this window, the animal should show no signs of awareness or pain response.
Bleeding: How Death Actually Occurs
Stunning alone does not kill the animal in most cases. It renders the cow unconscious so the next step, called exsanguination, can be performed without the animal feeling anything. After stunning, the cow is typically shackled by a hind leg and hoisted onto an overhead rail. A worker then makes a deep cut across the neck, severing the carotid arteries and jugular veins. This causes rapid, massive blood loss, which drops blood pressure to the brain and results in death.
The anatomy of cattle creates one complication worth noting. Unlike sheep, cows have vertebral arteries that run close to the spinal cord, protected by the neck vertebrae. These arteries are not reached by the throat cut and can continue supplying some blood to the brain even after the carotids are severed. Multiple researchers have documented this, with Temple Grandin noting that “in cattle, the vertebral arteries can still supply blood to the brain after the carotids are cut.” This is one reason pre-stunning is considered so important for cattle: without it, the animal could potentially remain conscious for a prolonged period during bleeding.
Religious Slaughter: A Legal Exception
U.S. law carves out an explicit exception for religious slaughter. Kosher (Jewish) and some traditional Halal (Islamic) slaughter methods involve cutting the throat without prior stunning. The legal language describes this as slaughter “whereby the animal suffers loss of consciousness by anemia of the brain caused by the simultaneous and instantaneous severance of the carotid arteries with a sharp instrument.”
In practice, a specially trained slaughterman uses an extremely sharp, long knife to make a single rapid cut across the throat, severing the windpipe, esophagus, and both carotid arteries. The idea is that the speed and sharpness of the cut, combined with the sudden drop in blood pressure to the brain, causes a rapid loss of consciousness. However, because of the vertebral artery issue in cattle, there is ongoing scientific debate about how quickly full unconsciousness occurs with this method compared to pre-stunned slaughter.
Some countries and Halal authorities have adopted a compromise approach. In New Zealand, for example, Halal slaughter of cattle uses head-only electrical stunning immediately before the throat cut. The stunning current is applied for 2 to 4 seconds, the animal collapses, and the ritual cut is performed within 10 to 15 seconds. This satisfies both animal welfare requirements and the religious authorities who have approved it, though not all Islamic scholars accept stunning as compatible with Halal principles.
What Happens Before the Kill Floor
The slaughter process does not begin with stunning. Cattle arriving at a processing plant are typically held in pens where they have access to water. They are then moved through a series of progressively narrower chutes that lead to the stunning area. Federal regulations require that this movement be done “with a minimum of excitement and discomfort.” In practice, facilities use curved chute designs that take advantage of cattle’s natural tendency to follow the animal ahead of them around a bend, reducing stress and balking.
The animal enters a restraining device, often called a knock box, that holds it in position for the stunner operator. The operator places the captive bolt gun against the forehead at a specific anatomical point and fires. If the stun is effective, the animal drops immediately. Federal inspectors from the USDA’s Food Safety and Inspection Service are present in slaughter plants and have the authority to stop operations if they observe inhumane handling.
After Bleeding: Processing the Carcass
Once the animal has been bled and confirmed dead, the carcass moves through a series of processing steps. The hide is removed, the head and hooves are taken off, and the internal organs are extracted. The carcass is then split in half down the spine using a saw, producing two “sides” of beef. These are rinsed, inspected for signs of disease, and moved into large coolers where they chill for 24 to 48 hours before being broken down further into the cuts consumers recognize: steaks, roasts, ground beef, and so on.
The entire process from stunning to initial carcass chilling is designed to move quickly. Speed matters not just for efficiency but for food safety, since delays allow bacterial growth. A large commercial plant in the United States can process several hundred cattle per hour.