Animal Handling- The Impact on Meat Quality and Economics

Animal handling is most commonly discussed from an ethical perspective. Public debate often focuses on animal welfare, transport conditions and the treatment of animals because of concerns for their well-being.

While these are important considerations, animal handling also affects the quality and economic value of meat. Stress, injuries and contamination can reduce product quality, increase production costs and create challenges for processors, retailers and other customers throughout the supply chain.

This article examines how animal handling influences meat quality and why it is also an important economic factor in professional meat production.

The Impact of Stress

One of the most important factors affecting meat quality is stress before slaughter. Transport, loading and unloading, unfamiliar surroundings, mixing with other animals or rough handling can all increase stress levels.

While these factors affect the animal immediately, they can also influence the biological processes that determine the quality of the meat after slaughter.

When pigs experience acute stress shortly before slaughter, their bodies react by releasing stress hormones such as adrenaline. Similar to a person performing an intense sprint, the muscles rapidly use their stored energy and produce increasing amounts of lactic acid.

Under normal conditions, blood circulation would continue to supply oxygen and remove these metabolic by-products once the effort has ended. After stunning, however, blood circulation stops. The lactic acid remains in the muscle, causing the pH to fall rapidly while the muscle is still warm.

This rapid change alters the structure of the muscle proteins and reduces their ability to retain water. As a result, more water is released from the meat than under normal conditions. This condition is known as PSE (Pale, Soft, Exudative) meat. Besides losing more water, PSE meat is typically paler in colour and softer in texture than normal pork.

In cattle, the opposite problem can occur. If animals experience prolonged stress before slaughter, they gradually use up much of their stored glycogen while they are still alive. After slaughter, there is not enough glycogen left to produce the normal amount of lactic acid, so the pH remains higher than normal. The meat becomes darker, firmer and drier, a condition known as DFD (Dark, Firm, Dry) meat.

PSE meat creates several challenges for the facility. One of the first is increased water loss during chilling.

After slaughter, every carcass naturally loses a small amount of water as it cools. Under normal conditions, this is around 1–2% of the carcass weight.

In PSE meat, however, the damaged muscle proteins can no longer bind water effectively. As a result, water loss can increase by up to 10%, reducing the final saleable weight of the product.

The following example illustrates the potential economic impact of additional water loss. The calculation uses an illustrative average carcass value of €1.60 per kilogram across the whole carcass. Individual cuts have different market values, so the figures should be understood as an overall illustration rather than the value of specific cuts.

Today, the incidence of PSE has been significantly reduced through improvements in genetics, transport, animal handling and slaughter practices. Although PSE still occurs, not every stressed animal develops the condition, and not every case results in the same increase in water loss.

However, the example illustrates why reducing stress before slaughter plays an important role in professional meat production. Even relatively small increases in quality defects can translate into substantial economic losses when thousands of animals are processed every day.

While the previous calculation illustrates the potential direct loss of saleable product, PSE meat can also create challenges further down the supply chain.

For retailers, PSE meat may be less attractive because it releases more water during storage and cooking. Consumers can notice excessive liquid in the packaging or in the frying pan, while the cooked meat may appear drier than expected.

For meat processors, the consequences can be even more significant. Products such as cooked ham depend on the meat's ability to bind and retain water throughout production. PSE meat has a reduced water-binding capacity, making it more difficult to achieve the desired product quality. To compensate, processors may need to use more functional ingredients and adjust their production process, increasing manufacturing costs. Even then, the final product may not meet the same quality standards as meat produced under normal conditions.

For the facility, this is not only a production issue but also a commercial one. Customers expect meat that performs consistently during further processing. If quality problems occur repeatedly, processors may seek alternative suppliers that can deliver more reliable raw material.

As a result, quality problems do not stop at the slaughter facility. They continue throughout the supply chain, affecting processors, retailers and ultimately the relationship between suppliers and their customers.

Measures to Reduce Stress

To reduce the risk of PSE, professional handling focuses on minimising unnecessary stress throughout the period between arrival and stunning. Several measures help achieve this.

Animals are unloaded as calmly as possible and are generally held in lairage (holding pens) before slaughter, where they have access to water and time to recover from transport. Throughout handling, unnecessary noise and rough treatment are minimised, while animals are usually moved in smaller groups and, where possible, kept with familiar animals to reduce fighting and social stress.

Facility design also contributes to calmer handling. Movement areas are designed to encourage animals to move naturally, for example by using gradual curves rather than sharp corners for pigs. In warm conditions, water sprinkling may also be used to help keep animals comfortable.

Operational planning also plays an important role. Coordinating farm collections, transport arrivals and processing schedules helps ensure animals have sufficient time in lairage before entering the next stage of the process. Better scheduling can therefore reduce unnecessary stress and help maintain consistent meat quality.

Together, these measures reduce unnecessary stress and help maintain consistent meat quality. Stress, however, is not the only factor that can influence the quality and commercial value of meat. The physical condition of the animal on arrival also plays an important role.

The Condition of the Animal

Animals can arrive at the facility with excessive dirt, mud, bruises, broken bones or other injuries. While these conditions are also undesirable from an animal welfare perspective, they can create operational challenges and economic losses throughout the production process.

One of the first concerns is excessive dirt. During cattle processing, for example, the hide is removed from the carcass. If the animal arrives heavily contaminated with mud or manure, bacteria from the outside of the hide are more likely to be transferred to the carcass if the process is not carefully controlled.

In pigs, excessive dirt can also make the cleaning process less effective. As more contamination enters the production process, maintaining hygiene standards becomes more challenging throughout the following processing stages.

Professional meat production relies on several microbiological barriers, often referred to as hurdles, to keep bacterial growth under control. Good hygiene, rapid chilling, vacuum packaging, curing, smoking and other processing methods each reduce the ability of bacteria to grow.

The effectiveness of these hurdles depends on the condition of the carcass at the beginning of the process. The cleaner the animal arrives at the facility, the easier it is for every following step to keep bacterial contamination under control. Higher levels of contamination at the start increase the challenge throughout the production chain, from the slaughter facility to meat processors and retailers.

For meat processors, this means the raw material enters the facility with a higher microbiological load. Although processors use their own hygiene systems and processing hurdles to control bacterial growth, starting with more contaminated raw material makes these systems more difficult to manage. This can increase production costs, reduce shelf life and, if quality problems occur repeatedly, affect customer relationships, brand reputation and the commercial value of the final product.

Physical Injuries

Open wounds create a different set of challenges. In professional meat production, animals with severe injuries or open wounds generally require additional veterinary assessment before entering the production process. Depending on the condition and the applicable regulations, they may be rejected from the normal process or require separate handling.

Besides causing pain and suffering for the animal, physical injuries can also create economic losses. Bruising, broken bones and other injuries caused by rough handling by people or by fighting between animals reduce the commercial value of the carcass.

Blood accumulates around damaged tissue, and fractured bones often require affected areas to be removed during further processing because they are no longer suitable for processing.

For cattle, careful handling is also important to protect the hide. Scars, bruises and other damage caused by rough handling on the farm or during transport can remain visible after tanning, reducing the quality and value of the leather. Since the hide is an important by-product of the beef industry, preventing unnecessary damage helps preserve its commercial value.

For this reason, professional animal handling begins on the farm and continues through transport, unloading and processing. Throughout each stage, good handling practices aim to minimise unnecessary stress, injuries and physical damage, supporting both animal welfare and the commercial value of the final products.

How these principles are implemented can vary between countries and individual facilities. Factors such as infrastructure, staff training, operational planning and regulatory oversight all influence how consistently professional handling practices are applied.

The Future of Professional Animal Handling

While modern slaughterhouses have significantly reduced many of the quality defects associated with poor animal handling, research and investment continue. The objective is to further improve animal welfare while enhancing meat quality, food safety and operational efficiency.

Current research is exploring alternative stunning methods that aim to reduce stress before animals lose consciousness. At the same time, improvements in transport planning, lairage management and production scheduling seek to create a smoother flow from arrival to slaughter, reducing unnecessary waiting times and handling.

Digital technologies may also contribute to future improvements. Camera systems, sensors and artificial intelligence can help monitor animal behaviour, identify signs of stress or injury earlier and optimise the movement of animals through the facility. Better planning of transport arrivals, resting periods and slaughter schedules may further reduce unnecessary stress before slaughter.

Animal welfare standards are also likely to continue evolving. Governments, retailers, veterinary authorities and animal welfare organisations all influence how animals are transported, handled and processed. While stricter standards can increase production costs, they may also improve meat quality, reduce product losses and strengthen consumer confidence throughout the supply chain.

Public discussions are often shaped by individual cases of poor animal handling. As with any industry, however, standards and practices can vary between countries, companies and individual facilities. This article focuses on the professional handling practices that are designed to reduce stress, contamination, injuries and the economic losses associated with them.

Although approaches differ between countries and facilities, the underlying principle remains the same: reducing unnecessary stress, contamination and injuries not only improves animal welfare but also supports food safety, meat quality and the economic performance of the meat supply chain.