Food Safety Magazine

COVER STORY | February/March 2009

Does Animal Welfare Affect Food Safety?

By Erika L. Voogd, M.S.

Does Animal Welfare Affect Food Safety?

This year, consumer interest has focused more than ever on “social responsibility” and sustainability for all industries, including agriculture. The media have been quick to publicize large meat recalls that are associated with humane handling or food safety concerns. Increasingly, consumers are looking closer at labels and becoming more aware of the potential (or perceived) advantages of making conscious choices. Included in these choices is an interest in knowing the welfare of the animals used for meat production. Labels such as “Animal Welfare Approved,” “Certified Humane Raised and Handled” and “American Humane Certified™” suggest that purchase of these products will provide assurances regarding the care and treatment of the animals. Does the welfare and humane treatment of food animals really affect the safety of the product? You bet!

From the moment of conception until the meal is served, producers and processors can provide the care, husbandry and attention to welfare that will assure the meat we eat is safe and nutritious, as well as accepted and appreciated by the consumer.

Defining Welfare
According to the Merriam-Webster dictionary, the definition of welfare is “the state of doing well especially in respect to happiness and well-being.” The definition of humane is “marked by compassion, sympathy or consideration for humans or animals.” This said, the humane treatment of animals considers the happiness or well-being of the animal as it relates to human compassion. As a significant segment of society, “meat consumers are increasingly demanding that animals be reared, handled, transported and slaughtered using humane practices.”[1] The challenge these days is finding an interpretation of “humane” that will meet the expectations of the animal behaviorist, the agriculture industry, the consumer, consumer-interest groups, government agencies and, ultimately, the animal.

Meat Production
The five freedoms
When considering the basic welfare needs of an animal, the most common definition is taken from the Farm Animal Welfare Council (FAWC), an independent advisory board established by the European government in 1979.

1. Freedom from Hunger and Thirst: by ready access to fresh water and a diet to maintain full health and vigor.
2. Freedom from Discomfort: by providing an appropriate environment, including shelter and a comfortable resting area.
3. Freedom from Pain, Injury or Disease: by prevention or rapid diagnosis and treatment.
4. Freedom to Express Normal Behavior: by providing sufficient space, proper facilities and company of the animal’s own kind.
5. Freedom from Fear and Distress: by ensuring conditions and treatment that avoid mental suffering.

Included with the definition of the five freedoms, the FAWC also emphasizes the importance of good stockmanship when rearing livestock and animals for meat or other use. “Stockmanship, plus the training and supervision necessary to achieve required standards, are key factors in the handling and care of livestock,” the FAWC’s web site states. “A management system may be acceptable in principle but without competent, diligent stockmanship, the welfare of animals cannot be adequately safeguarded. We lay great stress on the need for better awareness of welfare needs, for better training and supervision.”

Differences in intensive versus traditional production
As modern agriculture has evolved to feed large populations and to minimize the labor, real estate and economic resources required, global production has shifted from small-scale, single-family, multi-species farms to large-scale, single-species, intensive production operations. One of the most common production methods involves confinement operations where hundreds or thousands of animals may be raised in a single feedlot, facility or building. The use of confinement operations optimizes a producer’s ability to manage many animals in a single area; however, this method brings with it a need for management controls to minimize diseases and maximize the efficiency of the operation.

Groups that oppose industrial farming often criticize the modern intensive methods because of welfare, environmental and health concerns. As a meat scientist with more than 25 years of experience viewing production animals on their final day of life, my opinion is that, regardless of the method of raising meat animals, dairy livestock or poultry, the greatest contributor to humane handling is management practices. A conscientious and well-educated producer with competent, well-trained employees and modern, up-to-date facilities can produce a meat animal that would be considered by most consumers to have met the five freedoms of animal welfare. Achieving all of the parameters that must be considered requires an expert team of specialists on the subject of animal genetics, facility design, nutrition, handling, reproduction and veterinary care. In addition, today’s modern producer must possess a passion and love for the animals. I truly believe that the best producers respect and adore the animals they raise because the challenges faced are far too many for a disinterested manager to overcome!

Defining the Effects of Stress upon Meat and Milk
The quality and safety of the meat is greatly influenced by management of the stresses associated with production, transport and harvest. Minimizing pain, fear and injuries requires calm, quiet handling and can improve the following meat-related issues:

Dark cutting meat
Dark cutting meat occurs most frequently from pre-harvest stress. There is a depletion of muscle glycogen prior to harvest such that the pH of the meat remains high (>6.0) post-mortem. This higher pH causes an increase in light absorption and water-binding abilities and can result in a dark, firm, dry (DFD) surface. DFD meat can facilitate bacterial growth of microbial organisms that would be inhibited by a more normal meat pH of 5.6 to 5.8. The shelf life may well be reduced by the higher pH. Some of the common stresses that can cause dark cutting meat are heat stress, cold stress (body heat loss and shivering), large temperature fluctuations, extended periods of stress (greater than 10 hours), an extended time without feed and some growth promotants.

PSE pork and poultry
Pale, soft and exudative (PSE) pork or poultry is one of the most common results of animal stress and occurs just prior to harvest. When an animal experiences anxiety or agitation, muscles become tense; muscle glycogen is utilized, resulting in the formation of lactic acid in the meat. Because the animal is harvested before the lactic acid can be eliminated, a rapid drop in muscle pH occurs post-mortem (<5.5). The meat loses water-holding capacity, the muscle bundles have an open texture and reflect light, creating meat that appears pale and watery. There is a greater drip loss associated with PSE meat, which can also provide moisture for microbial growth, and thus PSE meat can have a reduced shelf life. As well, when the meat is cooked and consumed, this “drip loss” can cause a dryer, tougher product. The most common causes of PSE in meat are the presence of the porcine stress syndrome (PSS) gene in pigs, rough handling, the use of an electric prod and environmental temperature fluctuations, especially as temperatures rise.

Blood spotting
Blood spotting or blood splash occurs in the meat when capillaries are ruptured prior to complete bleeding of the animal. The meat appears to have small pink or red spots on the muscle surface. These pinpoint hemorrhages can be caused by excessive restraint, surface abrasions, poor stunning, increased stress just prior to stunning, slow or ineffective bleeding and some dietary factors such as low levels of selenium or vitamin E. Blood splash is considered a cosmetic defect, although blood spots have a higher pH and can provide an ideal medium for bacterial growth in the meat.

Bruising
Bruising can occur if animals are highly excited. Nervous animals are more likely to run, slip, fall or bang into gates, doors or other animals. Rough handling during transport or handling in pens, chutes and stun boxes can also cause bruising. It is a regulatory requirement to remove bruises from meat; however, it is possible that whole-muscle cuts could contain hemorrhages that would not be detected by employees during fabrication of meat cuts. Internal bruising can reduce the shelf life of meat due to the higher pH of the blood.

Dairy somatic cell count in milk
History has proven that rough handling of dairy cows lessens the flow of milk and can also increase the microbial count in the milk. A recent study performed by Fulwider et al.[2] found that dairies with a higher percentage of cows that either approached or touched the observer had lower somatic cell counts in the milk. A previous study indicated that reducing fear in dairy cows can increase milk yield by up to 10%.[3] Translation: dairy cows that are comfortable around people show less fear and can produce more high-quality milk.

Immune system response
Studies indicate that short-term stresses and long-term, chronic pain increase cortisol levels and can greatly reduce the body’s immune function. A lowered immune system allows common enteric pathogens and somatic cells to flourish. The outcome can be infections such as laminitis, lesions, mastitis and other bacterially related illnesses. This stress also can facilitate fecal shedding of enteric pathogens such as Salmonella, Campylobacter and E. coli O157:H7. All of these pathogens have been linked to foodborne illness outbreaks from raw meat products.

Production Practices that Affect Animal Comfort
Genetic selection
As a result of genetic selection for production characteristics, intensive raising and high-energy feed inputs, many of the animals used for meat, dairy and egg production may be subject to a reduced immunity, an excitable disposition and/or lameness. A 1997 study by Voisinet et al.[4] found that cattle with an increased temperament score (more excitable) had a decreased average daily weight gain. A Feedstuffs article published in 2008 states that in 2007, 15.2% of sows were culled from pig production for lameness.[5] The same report indicates that in 2002, 16.3% of dairy cows were culled for lameness and 26.9% for mastitis and udder ailments. Universities and livestock industry health professionals are working diligently to provide information to producers regarding methods to improve animal comfort and health during production.

A 2008 study conducted by Almeida Paz et al.[6] utilized scoring of the femur head for lesions or dislocation and radiographic analysis to determine the density of femoral bones to estimate the degree of femoral degeneration (leg weakness) in 42-day-old broiler chickens at the time of harvest. The data suggested that because of increased rate of gain, male broilers had a higher degree of femoral degeneration than females and that the lesion incidence rate was higher than 81% for the broilers. This study determined that as broiler locomotion decreased and gait score increased, the bone density and degree of femoral degeneration increased. This suggests that the selected genetics of the modern broiler may be causing leg weakness and distress to the animal.

Biosecurity has become an increasing concern for today’s animals that are genetically selected for high production. There is a reduction in “hybrid vigor” and modern, intensively raised animals can easily spread disease due to the close proximity of large numbers of animals. Production facilities often require routine hygiene measures for employees, visitors and transport vehicles, such as controlled facility access, “shower in and shower out,” heat treatment of transport trucks and the donning of protective coveralls, footwear and hair nets prior to entry into the facilities.

Antibiotic resistance
To optimize production and minimize diseases in meat-, dairy- and egg-producing animals, many producers add sub-therapeutic antibiotics to the feed. “The Union of Concerned Scientists estimates that at least 70% of the antibiotics used in America are fed to animals living on factory farms.”[7] The use of these antibiotics is now being reviewed, as evidence suggests that pathogens that are detrimental to humans have developed resistant strains due in part to antibiotic use in animals. As Michael Pollan reports in a New York Times article,[8] “Recent studies in Europe and Canada found that confinement pig operations have become reservoirs of MRSA (methicillin-resistant staph). A European study found that 60% of pig farms that routinely used antibiotics had MRSA-positive pigs (compared with 5% of farms that did not feed pigs antibiotics).” A second study just published in November by Johns Hopkins University’s Bloomberg School of Public Health[9] “found evidence of a novel pathway for potential human exposure to antibiotic-resistant bacteria from intensively raised poultry—driving behind the trucks transporting broiler chickens from farm to slaughterhouse.” On December 4, 2008, the National Chicken Council issued a press statement criticizing many aspects of the transport study. Because of the perceived concerns outlined above, many consumers are now choosing meat, milk and eggs labeled as organic, natural or antibiotic-free.

Consolidation and Transport
The importance of calm handling is no more beneficial than in the last 24–36 hours of the animal’s life. Stress at this point can destroy months or years of hard work to raise productive, healthy meat animals. Auction and consolidation points are also critical moments for minimization of stress as livestock are exposed to unfamiliar surroundings and animals. Experienced handlers will recognize the importance of quiet, calm handling at this crucial step!

To facilitate smooth loading and transport, the key industry groups have developed trucker certification programs. The Pork Checkoff introduced the Transport Quality Assurance (TQA) program in February of 2002. The course includes information on handling, loading and unloading, transportation, fitness of the pig, biosecurity, emergency response, laws and regulations and transport. Since the program’s inception, most of the large pork processing plants have required that truck drivers be TQA-certified prior to hauling livestock to the company plants. The National Cattleman’s Beef Association has a similar program, the Master Cattle Transporter Guide. From a food-safety standpoint, vehicle hygiene and calm handling can both reduce the incidence of injuries and fecal pathogens in meat animals.

Harvest
According to the American Meat Institute (AMI) Foundation’s animal handling web site, www.animalhandling.org, “Since 1991, the AMI Foundation has encouraged its members to subscribe to voluntary animal welfare guidelines and to embrace auditing programs, and they have done so. The meat industry was the first sector in animal agriculture to develop such guidelines and to begin self-audit programs.”

In 1999, the AMI and McDonald’s Corp. sponsored the first Animal Care and Handling Conference in Kansas City, MO. Since that first meeting, this conference has become an annual event, sponsored by food industry organizations such as the Food Marketing Institute (FMI), the National Grocers Association (NGA), and the National Restaurant Association (NRA), as well as agricultural organizations such as the National Cattlemen’s Beef Association, the National Pork Board, the American Association of Bovine Practioners (AABP), the American Association of Swine Veterinarians and the Animal Agriculture Alliance. With the help of AMI’s Animal Welfare Committee, the conference features a variety of academic and industry experts. Conference subjects include general sessions, introductory and advanced tracks on humane handling of beef and pork, as well as a separate concurrent session focused on management and policy. Biennially, the AMI conducts a separate International Meat Animal Welfare Research Conference and has also offered specialty classes in livestock transportation.

Large-volume meat plants have developed quite extensive humane-handling programs, which include written procedures, documentation of training, maintenance records and daily or weekly internal audits. Most large plants also utilize third-party organizations to perform an independent humane-handling audit, at least annually. Because of implementation of humane handling programs, meat plants have experienced improvements in meat quality and food safety, and a reduction in employee-related safety concerns.

Controlled-atmosphere stunning
Welfare-conscious groups have issued studies suggesting that controlled-atmosphere stunning of poultry is more humane than electrical stunning of birds. Quick-service restaurant chains, such as Wendy’s International, Inc. and Burger King Corp., have announced a purchasing preference for poultry meat from harvest plants that utilize controlled-atmosphere stunning rather than the traditional method of live-hanging birds upside down by the legs and electrically stunning them. Controlled- atmosphere stunning of pigs versus restraint and electrical stunning has also reduced overall stress. There is a reduction in animal stress in large, CO2-stunning systems, as the animals can be moved in small groups rather than individually, without the need for restraint. Plants utilizing CO2-stunning systems report a lower incidence of PSE, bruising and blood splash in the meat.

Global Success Stories
The true benefits of humane handling are most easily measured by just that: measuring. Below are examples of how the awareness, education and auditing of the process has resulted in meat quality, food safety and humane handling improvements.

Controlled-atmosphere stunning of turkeys
In 2000, the Michigan Turkey Producers Co-op Incorporated (MTP) opened a state-of-the-art processing plant to harvest locally grown turkeys. The company utilizes an automated catching and conveying system that moves groups of turkeys into transport crates without the need for hand catching. The plant uses a controlled-atmosphere stunning (CAS) system that utilizes CO2 to stun birds while still housed in large group containers, again eliminating the need for human handling. This method of harvest is considered more ergonomically safe for the employees, who do not need to handle heavy, live birds, and also provides food-safety benefits. Animal stress is minimized as the birds are not handled by humans until after stunning is completed. The Salmonella performance data for over 200 MTP tests shows a rate of 1.43% positive (Figure 1). This rate is 76% lower than 2007 USDA data for Salmonella performance tests of turkey carcasses (6.2%). The use of CAS also provides improvements in PSE and meat color as well as a higher deboning yield, decreased bruising, lower incidence of broken wings and fewer blood spots in the meat.

Preparing pigs for transport
Kowi, a pork operation in Mexico, measured several meat parameters and determined that the amount of PSE in finished meat varied by farm. When the lowest PSE farms were asked about their procedures, it was discovered that the day prior to transport, the pigs were moved to a staging pen. This familiarized the animals with movement to a new environment, prior to transport, greatly reducing the stress associated with truck loading and transport. Also, the harvest plant’s animal-handling operators received training to assure calm handling, and the CO2-stunning system was modified to improve animal movement. The result was a decrease in drip loss and PSE for pork products.

Improved handling of pigs
The Pronaca pork plant in Ecuador was experiencing internal muscle bruising, capillary rupture and PSE on the 1,000 pigs that were processed each day. In April of 2007, a humane-handling team was developed and trained. The team determined that improvements in transport, truck unloading and animal cooling, as well as gentle handling and the elimination of distractions, could dramatically improve the meat products. Weekly humane-handling audits measured the effect of each change and clearly demonstrated the value of the team’s efforts. Measurement of key meat parameters showed an increase in muscle pH and a substantial reduction in economic losses due to meat-drip loss (Figure 2).

Poultry handling measures
Pipasa is probably the largest, most recognized poultry supplier in Costa Rica. In March of 2005, the company had yet to fully embrace the benefits of humane handling. In a country where warm days can mean temperatures of +32 °C, cooling of the birds during holding is critical. Overheating can cause heat stress, dehydration and possibly even premature death. Some fans in the truck-holding area and receiving dock were not working efficiently and not all of the misters were operating effectively. In some areas, birds were observed panting and showed signs of heat stress. There is an economic advantage to having a good cooling system for reducing bird stress, yield loss and improving meat quality. This was communi- cated to the team at Pipasa.

Initially, the plant had some challenges with the stunning system inconsistently stunning the birds. This resulted in red wing tips and some “pink” muscling. The bleed machine was not always working effectively and on occasion, although the birds died, some blood remained in the animal, especially in the neck and head. Pipasa is a McDonald’s supplier and was able to obtain the assistance of a “sister” McDonald’s poultry plant to provide ideas for making effective improvements. Pipasa quickly implemented these changes and opened their doors for further animal-welfare training.

By May of 2005, new fans and misters had been installed in the holding area. The stunner had been modified and birds were being stunned quite efficiently. The bleed machine was working completely and the meat quality was already showing improvements. Pipasa had implemented a daily auditing program and was just starting to record results.

By September of the same year, there was a dramatic difference in meat quality observed. The meat no longer showed signs of inefficient bleeding, red wing tips or bruised muscles. The previous challenges were now history. The animal welfare team presented a 4-inch-thick notebook of daily audits and a chart showing a series of quality measures, by farm and the corrective actions taken if any issues were noted. It was quite clear that not only had the chickens benefited by these changes, but also the Pipasa management and customers. Pipasa can be quite proud of all of the progress that was made in a few short months.

Beef plant successes with video surveillance
The infamous Chino, CA plant once known as Westland Hallmark reopened its doors in November 2008 under new ownership as American Beef Packers, Inc. The team worked diligently to develop a highly advanced humane-handling program, which included three days of training for management and handlers, prior to opening. Additionally, the plant installed 13 real-time video cameras, capable of remote monitoring by plant management, consultants and the video surveillance manufacturer, which issues a weekly audit report summarizing random “spot audits” of handling measures for receiving of livestock, holding, moving and stunning of cattle. Dr. Temple Grandin, world-renowned animal welfare expert, recently viewed the ABP plant video cameras from a remote location and stated that, “based on the AMI guidelines, the plant was passing for all measures observed.”

The Future
You know that humane handling and animal welfare are becoming mainstream issues when they are featured in USA Today, The New York Times and on the nightly news or The Oprah Show. For this reason, it is necessary now more than ever for the agriculture industry to establish and communicate a proactive approach to animal management. The industry has responded to this suggestion with many mainstream vehicles, such as YouTube videos of livestock producers, public relations web sites and “Ag in the Classroom” educational materials (www.agintheclassroom.org).

Producer considerations
It is important for the producer to consider the following parameters to optimize production and minimize welfare concerns:

• Breeders need to focus on selection for animals with traits beyond merely production efficiency. They must also select for animals with a strong frame, disease resistance and a calm temperament.

• Producers need to consider the type of production system in which the animal will be raised. For example, exposure of “confinement” broilers to a “free-range” farm in a cold environment could result in high morbidity and mortality, as this animal has been bred for a protected and controlled environment and would not have the structure, immunity and instincts necessary to survive in a harsher climate.

• Production nutrition needs to consider skeletal frame growth prior to muscle development to minimize lameness and the physiological or dietary conditions that can cause animal discomfort.

• Production facilities should be designed to provide animal comfort and prevent injuries from hoof wear, foot ailments, slipping and falling.

• Management practices need to incorporate sanitation, veterinary care and monitoring to minimize and rapidly treat mastitis and foot and leg ailments.

• The food industry, as a whole, needs to revisit the reasons for and use of subtherapeutic antibiotics, considering alternative breeding, biosecurity, housing, and feeding to address the potential evolution of dangerous “super bugs.”

• Production management and employees need to be aware of the importance of calm, low-stress handling to acclimatize animals to humans prior to harvest. This is especially important for operations utilizing range production. Animals must be accustomed to seeing humans on foot, not just on horseback.

• Production breeding facilities must utilize a cull program with “timely replacement,” well before the animals reach a non-ambulatory or compromised state. Very sick or injured animals that are non-ambulatory and not expected to make an immediate recovery should be euthanized as quickly and humanely as possible.

• It is important for producers and production employees to operate with a “herdsman” philosophy of respect for the animals. Education and communication are crucial to assure that handling expectations are in place.

• It is beneficial to establish key measures to assure compliance. Examples of welfare-related production measures are included in the following industry programs: Dairy Quality Assurance (DQA), Pork Quality Assurance (PQA) and Beef Quality Assurance (BQA).

Consumer education and communication
Just as important to humane handling and animal welfare is the aspect of consumer perception. Consumers need to be educated regarding animal needs versus “anthropomorphic” expectations of animal comfort. Many organizations, such as the National Cattlemen’s Beef Association, the National Pork Board and the National Chicken Council, work to educate United States consumers regarding modern agricultural production. In Canada, the major agricultural provinces have established proactive, nonprofit organizations designed to provide an educational link between the industry, producers and consumers. Established in 1992, the Farm Animal Council of Saskatchewan Inc. (FACS) is the first industry-supported, membership-based, nonprofit, provincial organization established to collectively represent the livestock and poultry industries regarding animal care issues. Our industry needs to become more proactive and transparent, sharing success stories among constituents, colleagues and consumers.

Erika L. Voogd, M.S., is president of Voogd Consulting, Inc., West Chicago, IL. She is currently working as an independent consultant specializing in global assistance to the meat industry. Her expertise includes animal welfare, food safety, HACCP, quality assurance, sanitation and USDA regulatory compliance. She received a Master’s degree in Meat Science and a Bachelor’s degree in Animal Science from the University of Illinois.

References
1. Appleby, M. C. and B. O. Hughes. 1997. Introduction, in Animal Welfare. Edited by M. C. Appleby and B. O. Hughes. Wallingford: CAB International.
2. Fulwider, W. K., T. Grandin, B. E. Rollin, T. E. Engle, N. L. Dalsted, and W. D. Lamm. 2008. Survey of Dairy Management Practices on One Hundred Thirteen North Central and Northeastern United States Dairies. J. Dairy Sci. 91:1686-1692.
3. Grandin, T. Hoard’s Dairyman, October 10, 1999.
4. Voisinet, B. D., T. Grandin, J. D. Tatum, S. F. O’Conner, and J. J. Struthers. 1997. Feedlot Cattle with Calm Temperaments Have Higher Average Daily Gains than Cattle with Excitable Temperaments. J. of Animal Sci. 75: 892-896.
5. Allerson, M., J. Deen, T. Ward, and M. Wilson. Sow health: Lameness not just a cow issue. Feedstuffs 80:22-28.
6. Almeida Paz, I. C. L., et al. 2008. Study on the bone mineral density of broilers suffering femoral joint degenerative lesions. Rev. Bras. Cienc. Avic. 10:103-108.
7. http://query.nytimes.com/gst/fullpage.html? res=9D04E7D6123AF93AA35752C0A9679C8B63
8. Pollan, M. New York Times Magazine, December 16, 2007, [see http://www.michaelpollan.com/]
9. http://www.newswise.com/articles/view/546778.

 

Categories: Regulatory: USDA