Livestock Handling Quality Assurance

Temple Grandin
Department of Animal Science
Colorado State University
Fort Collins, CO 80523


Careful handling of pigs and cattle at the slaughter plant will help preserve meat quality. Cattle handled quietly have less bruising and cattle which remain calm during handling are less likely to have dark cutting or tough meat. In pigs, quiet handling and a minimum of electric prod use in the stunning chute will reduce PSE approximately 10 percent. Meat damage from poor injection technique may be reduced in animals that are handled quietly. Proper injection technique is easier in calm animals. People manage what they measure. Objective scoring should be used to measure the quality of handling. Vocalization scoring can be used to assess handling quality. The percentage of cattle that vocalize (moo or bellow) during handling through chutes is tabulated. Other measures are the percentage of animals prodded with an electric prod and the percentage of cattle that walk quietly into a squeeze chute. Cattle that walk quietly into the squeeze chute are less likely to get shoulder injuries which cause extensive meat damage. Cattle that are handled quietly with a minimum of electric prod use will vocalize less than cattle that are excessively prodded with an electric prod. Squeal scoring can be used in pigs to assess handling quality. Several studies show that vocalization is correlated with physiological measures of stress in both cattle and pigs.

Introduction - Handling and Quality

Quiet careful handling of cattle and pigs during all phases of production will help preserve meat quality. Voisinet et al. (1997a,b) reported that cattle that became agitated during handling in squeeze chutes had significantly lower weight gains, tougher meat and more borderline dark cutters. Dark cutting beef is darker than normal and it has a shorter shelf life. It is a severe quality defect. Practical experience and observations by the author at feedlots and slaughter plants indicate that wild excitable cattle have more dark cutters. Quiet handling also provides the advantage of significantly reducing bruising (Grandin, 1981).

Injections in muscle cause extensive meat damage (George et al., 1996 and George et al., 1997). Damage from injections in the muscle are long lasting. Injections given to calves at branding or weaning can still cause meatdamage (George et al., 1995ab). George et al. (1995a) found that injections in the muscle can cause a sphere of toughness the size of a baseball. Quiet handling is important because it is easier to properly give subcutaneous injections when cattle are standing still in a squeeze chute. When agitated, cattle struggle it is more difficult to administer injections in the correct position on the neck to help prevent meat damage. Agitated cattle that hit the headgate too hard can sustain extensive injuries which may destroy a large portion of the shoulder meat.

Handling pigs quietly will help prevent PSE. PSE is a serious quality defect that makes the pork pale and it has poor water binding capacity. Retailers are willing to pay a premium for pork that does not have PSE (Von Rohr, 1999). The last five minutes prior to stunning is critical. Observations by the author in four different U.S. plants have shown that reducing electric prod use, squealing and pile ups resulted in 10% less PSE. Researchers have confirmed that stressful preslaughter handling will cause a deterioration of pork quality (Warris et al., 1990; D’Souza et al., 1998 and Van derWal, 1997). The elimination of electric prods also reduces blood splash (petechial hemorrhaging) in the pork (Calkins et al., 1980; Robin Warner personal communication, 1999). Blood splashed meat has red spots in it and it cannot be sold as premium product.

Blood splashing is also a problem in Kosher cattle. The author has observed in four different plants that Kosher cattle that are slaughtered without stunning often have two to three times as more blood splash compared to cattle stunned with a captive bolt. Reducing or eliminating electric prod use and keeping cattle calm in the restraining box will help reduce blood splash (Grandin, 1994; Grandin and Regenstein, 1994). The first part of this paper will review the extent of handling related meat quality problems and the second section will cover the use of auditing methods which will help maintain quiet careful handling of livestock. To maintain handling quality it has to be measured on a continuous basis to maintain a high standard of handling quality.

Review of Handling Related Quality Problems


Forty-eight percent of U.S. fed steers and heifers have bruised carcasses (Boleman et al., 1998; Smith et al., 1995). Studies in both sheep and cattle indicate that animals sold through auction markets have more bruises than animals sold direct to a slaughter plant (Cockram and Lee, 1991; McNally and Warriss, 1996; Hoffman et al., 1998). Bruising on cull cows is extensive. Damage to cow meat is becoming a greater economic issue because 44% of the beef from cull cows is sold as primals and 100% visual lean suprimals (Smith, et al., 1999). Twenty-two percent of cull cows had severe bruising and 2.2% had severe bruises which destroyed a major portion of the carcass (Smith et al., 1999). A recent Canadian study showed that 15% of the cattle had severe bruising and 78% of carcasses had some bruising (Van Donkersgoed et al., 1997). A comparison between the 1994 and 1999 audit of cull cows indicates that economic losses from bruises declined from $3.91 to $2.24 per cow (Smith et al., 1999). Even though there has been some improvement, the losses are still very extensive.

Injection Site Damage

Smith et al. (1999) reports that losses from injection site lesions has become worse in cull cows. The cost rose from 66 cents in 1994 to $1.46 in 1999. Much of this increase was in dairy cows. The author has observed that most feedyard personnel are injecting steers and heifers in the neck to avoid damage to the most valuable parts of the carcass. In beef cattle the majority of lesions showing up in the top butt and expensive cuts have occurred before the animals came to a feedlot (Boleman et al., 1998).

Interviews with a major western packer indicated that in fed cattle most of the injections were given in the neck or shoulder but many of the injections penetrated the muscle and were not given subcutaneously. Many squeeze chutes have long neck extender bars on the headgate to hold the head for administration of growth promotant implants in the ear. The author has observed that these bars make it almost impossible to give an injection properly in the neck. The extender bars cover up the neck. The author estimates that about half the feedyards use neck extender bars which interfere with giving subcutaneous injections in the correct location on the neck.

Dark Cutting Beef

Scanga et al. (1998) reported that the average percentage of dark cutters in nine different feedyards varied from 0.64% to 0.05%. Data was compiled from 15,439 pens of feedlot cattle. Schiefelbein (2000) collected data on 55,876 cattle of eight different breeds. The average dark cutter percentage was 0.37%. The average percentage of dark cutters for each breed were: Red Angus 0.08%, Charolais 0.26%, Gelbvieh 0.28%, Hereford 0.30%, Black Angus 0.40%, Salers 0.62%, Simmental 0.82%, and Limousin 0.99%. The breeds with a calmer temperament had a lower percentage of dark cutters. Both packers and feeders have observed that groups of cattle which became highly agitated during handling sometimes have up to 20% dark cutters. Many factors contribute to causing dark cutters. Aggressive use of growth promotant implants and weather extremes also increase dark cutting (Scanga et al., 1998). Other factors are, breed of cattle or excitement and agitation during handling (Voisinet et a., 1997b and Schiefelbein 2000). Stockyard practices can also contribute to the depletion of glycogen that causes dark cutting. Mixing strange cattle from different pens or pastures will increase dark cutting (McVeigh and Tarrant, 1983; Warris et al., 1984; and Grandin, 1978-1979). Two feedlot managers reported that eliminating electric prods during loading of fed cattle into trucks greatly reduced dark cutters.

Pale Soft Exudative Pork and Death Losses

Morgan (1993) reported that 9.1% of all hams and loins processed in the USA had PSE. Genetics is a major factor in causing PSE (Lundstrom et al., 1989 and Sather et al., 1991).Death losses in pigs are related to both genetics and handling. Canadian researchers Murray and Johnson (1998) reported on a Canadian study that death losses were 9.2% in PSS homozygous positive pigs, 0.27% in carriers and 0.05% in homozygous negative pigs. Pigs which have the PSS gene also have more PSE (Sather et al., 1991). The author has observed in three packing plants that both death losses and quality problems are highest in very heavy 125-kg pigs that carry the stress gene (Grandin 2000a). Weather extremes also increase death losses and PSE. The author has observed in several plants around the U.S. that PSE often increases when the first hot days begin in spring. High temperatures and humidity will increase death losses (Warriss and Brown, 1994). Keeping pigs cool and careful quiet handling can help reduce both PSE and death losses. Resting pigs for two to four hours prior to stunning will significantly reduce PSE (Malmfors, 1982; Milligan et al., 1996). Showering pigs cools them off and will also reduce PSE (Smulders et al., 1983). When pigs get excited they get over heated and an over heated pig is more likely to have poor quality pork (Gariepy et al., 1989).Careful quiet handling and reducing electric prod use will help prevent pigs from getting overheated. Brundridge et al., 1998 has found that using an electric prod significantly raised a pig’s heart rate. Minimizing electric prod use in the stunning chute will reduce PSE (Grandin 2000; Robin Warner, 1999, personal communication).

Blood Splash in Pork and Kosher Cattle

A complete discussion of the effect of stunning method on blood splash is beyond the scope of this paper. Stunning method does have a significant effect on the levels of blood splash (Gilbert and Devine, 1982; Velarde et al., 1999). The discussion in this paper will mainly cover handling. In numerous plants the author has observed that lean pigs are more prone to blood splash than pigs with thicker fat. Elimination of electric prods will reduce blood splash (Calkins et al., 1980; Robin Warner, 1999 personal communication). When pigs squeal and pile up they are more likely to stretch their skin and break small capillaries. In sheep, the angle of the side of the conveyor V restrainer affected the incidence of blood splash (Thorton et al., 1979). Grandin (1985) found that running pigs through a broken V restrainer with one inoperative side conveyor stretched and pulled the skin and increased blood splash.

Blood splash is a severe problem in Kosher (Jewish ritual) slaughter which is done without stunning. Practical experience indicates that it may be a greater problem in grainfed cattle compared to grassfed cattle. In four Kosher plants, the author has observed that captive bolt stunning immediately after the throat cut brought about a three-fold reduction in blood splash compared to Kosher slaughter without captive bolt stunning. Data obtained from plant records indicated that carefully done Kosher slaughter of grainfed cattle without stunning still produced 3 to 4% blood splashed carcasses. Blood splash and blood spotting was assessed by looking for petechial hemorrhages on the ribeye during grading. When cattle became excited and agitated due to excessive use of electric prods and struggling during restraint, blood splash can rise to 30% of the carcasses. A good operator of a properly designed upright restraint box can greatly reduce blood splash because he/she minimizes pressure exerted on the rear of the cattle with the pusher gate. The design of the box is shown in (Grandin and Regenstien 1994, Grandin, 1994). Data collected at a large glatt Kosher plant indicated that the percentage of carcasses with blood splash was 3.5% with a skilled restraint box operator and 10% with a poorly trained operator. All the kosher cattle in this plant were grainfed. The cattle were held in an upright standing position when the throat cut was made. In a regular plant where cattle are stunned with a captive bolt, blood splash levels are usually less than 0.5% of beef carcasses.

Excessive blood splash in Glatt kosher cattle where captive bolt stunning after the throat cut is not permitted has caused some plants to leave the grainfed kosher business. Keeping cattle calm during handling, minimizing the time that the animal is restrained and avoiding excessive pressure applied to the body will reduce blood splashing (Grandin and Regenstein, 1994). For animal welfare reasons the animal should be restrained in a device that holds it in a comfortable upright position during the throat cut (Grandin, 1994; Grandin and Regenstein, 1994).

Problem of Maintaining Good Handling Practices

It is clear from both scientific studies and practical experiences that proper handling practices will help prevent damage to the meat and other quality problems. In many different slaughter plants the author has documented a substantial reduction in bruises, blood splash or PSE by training employees and improving handling. In one kosher beef plant, a $500 to $1000 loss per day due to blood splash was prevented by stopping the excessive use of electric prods and operating the restraining box correctly to prevent excessive pressure from being applied to the animal’s body. In three pork plants, a 10% improvement in the acceptance rate for Japanese export occurred when handlers were trained to reduce electric prod use and to move smaller groups of pigs.

Unfortunately in all four of these plants, handling practices gradually slipped back into their old rough habits. This happened because the quality of handling was not continually monitored on a regular basis. There was a one time effort to improve handling and then management’s attention was shifted to other parts of the plant. They failed to maintain good handling practices even though the financial loss was well documented.

In many other slaughter plants and feedlots, the author has observed a gradual deterioration in handling practices after a one time training session had improved handling. In some cases, the deterioration occurred slowly and the people did not realize how poor their practices had become because they had nothing to compare their performance to. The author conducted a survey in 1996 for the U.S. Department of Agriculture of handling practices in 21 beef and pork plants. Seven (33%) of the plants were rated a serious problem for abusive use of electric prods (Grandin, 1997a). In one plant, bulls were paralyzed with an electric prod. The survey was an announced USDA visit and bad practices were observed because management had come to view these practices as “normal.”

Auditing Handling

Managers manage the things that they measure. One of the reasons why handling practices deteriorated after training was because the quality of handling was not measured on a regular basis. Monitoring handling on a regular basis would be similar to monitoring bacteria counts for food safety. A plant’s food safety program can maintain low bacterial counts because counts are continuously measured. It is likely that bacterial counts in meat and on equipment would gradually increase if measuring on a regular basis was discontinued.

Auditing of the critical control points of handling will help maintain handling standards to insure good animal welfare and help preserve meat quality. Grandin (1998a) developed an objective scoring system for handling and stunning at slaughter plants. The system is simple so that it can be easily implemented. It was essential to find the important critical control points, but not have too many things to measure. The variables measured are 1) Percentage of animals stunned correctly on the first attempt, 2) percentage of animals insensible on the bleed rail, 3) percentage of cattle that vocalize (moo or bellow) during movement through the chute and restrainer, or the percentage of time that pigs are squealing in the stunning area, 4) percentage of animals electric prodded and 5) percentage of animals that slip or 6) percentage that fall (Grandin, 1997b). A minimum of 100 animals are scored in large beef and pork plants and 50 animals in small plants with a line speed of less than 100 per hour.

To keep the auditing process simple, each variable is scored on a yes/no basis for each animal. For example, vocalized, yes or no, electric prodded - yes or no. Attempting to determine the intensity of a cattle vocalization is not practical under commercial conditions.

Vocalization Scoring

In cattle, the percentage of cattle that vocalize is a sensitive indicator of problems such as excessive electric prod use, slipping in the stunning box, excessive pressure applied by a restraint device and missed stuns (Grandin, 1997a). Vocalization scoring can be used to monitor improvements or a deterioration of handling quality. A lone bovine left in a crowd pen or stun box too long will often vocalize. A reduction in the use of electric prods is associated with a significant reduction in the percentage of cattle that vocalize. Grandin (1998b) reports that reducing the percentage of cattle electrically prodded from 90% to 14% reduced the percentage of cattle that vocalized form 32% to 13%. The 13% that still vocalized were responding to excessive pressure applied by a restraint device. In a second plant, the percentage of cattle electrically prodded was reduced from 76% to 20% and the percentage of cattle that vocalized dropped from 12% to 3% (Grandin, 1998ab). Grandin (1998ab) reported that 98% of the vocalizing cattle were associated with an obvious aversive event such as prodded with an electric prod, missed captive bolt stuns, slipping in the stun box, excessive pressure from a restraint device or being left alone too long in a chute or stun box. Further data collected in 21 beef plants indicated that the average percentage of cattle that vocalized was only 3.08% and the range was 0.66% to 17% (Grandin 2000b). The plants scored in Grandin (2000b) had a lower percentage of cattle that vocalized compared to Grandin (1998a) because the employees were demonstrating their best behavior. The plants in Grandin (2000b) were being audited for animal welfare by McDonald’s Corporation. Therefore an electric prod was only used on cattle that refused to move. Ten plants (48%) which had low or no electric prod use had 1% or less of the cattle vocalizing (Grandin, 2000a). Four plants (19%) had higher percentages of 7, 8, 12, and 17% vocalizing (Grandin 2000b). These elevated percentages were due to excessive electric prod use on cattle that constantly balked and backed up. In one plant that had 8% of the cattle vocalizing, the cattle were balking at a dark restrainer conveyer entrance. Another 100 cattle were scored after a light was installed to illuminate the entrance. The percentage of cattle that vocalized dropped to zero because balking was greatly reduced and the use of electric prod was also reduced.

Vocalization in both cattle and pigs is correlated with physiological measures of stress (Dunn, 1990; Warriss et al., 1994b, Lay et al., 1992, Weary et al., 1998 and White et al., 1995). In pigs, the intensity of squealing was related to poorer pork quality (Warriss et al., 1994). Vocalization scoring provides a simple way to identify problems with excessive electric prod use or other problems with equipment or handling. Data from both Grandin (1998b, 2000b) indicate that plants which have more than 3% of the cattle vocalizing during handling usually have a problem such as excessive electric prod use or a poorly maintained captive bolt stunning. Vocalization scoring is only done when animals are being moved through the chute stun box or restrainer. Animals standing undisturbed in the holding yards are not scored. Vocalization scoring also provides an easy way for a plant to audit its own handling practices. Excessive use of electric prods will usually be reflected by a higher percentage of cattle vocalizing. People auditing vocalization must be observant because sometimes the aversive event associated with vocalization is not readily apparent. At one beef plant, some cattle vocalized loudly in a conveyor restrainer. The restrainer was in good repair, but a local welding shop had built replacement conveyor slats wrong. They had a variation in height of over 2 cm from one slat to the next. This welding shop mistake created sharper corners that stuck into the cattle.

Watts and Stookey (2000) report that there are genetic differences in the tendency of certain genetic lines of cattle to vocalize. All the beef slaughter plants that minimized electric prod use, had a first shot stunning score of 95% or better, had non slip flooring and no problems with their restrainer such as sharp edges had a vocalization percentage of 3% or less of the cattle (Grandin 2000b). Three percent is the minimum passing score on the American Meat Institute guidelines (Graindin 1997b). Watts and Stookey (2000) are concerned that a plant could get an acceptable vocalization data percentage with one group of cattle and fail with another. The author has collected vocalization in over 50 beef plants on more than 4000 cattle. There were only two groups of 50 and 100 cattle that had more than 5% of the cattle that spontaneously vocalized while moving through the chutes when there was no aversive event such as an electric prod used associated with the vocalization. One group was 19 mature cull bulls that were handled together in a single group. The other group were black fed heifers of unknown genetics which had no visible Brahman characteristics. If an auditor encounters a group of cattle that appear to be vocalizing without an aversive event present, it is recommended to score several more groups of 100 cattle from different origins. In the plant with the black heifers, the vocalization percentage dropped to less than 3% when other groups of cattle were scored. It may not be advisable to apply the 3% pass rate to mature bulls handled in groups.

It is likely that cattle which vocalize without an associated obvious aversive event are cattle that are more easily stressed. The author has observed in both feedlots and plants that highly vocal cattle also tend to get more agitated and struggle more during handling in squeeze chutes in feedlots. These cattle will need careful handling to reduce stress because cattle that become agitated during handling are more likely to have meat quality problems or lower weight gains (Voisinet et al., 1997ab).

The author has also observed that pigs with an excitable temperament are more likely to squeal when slapped on the rear. These pigs are more likely to pile up during handling and they are more likely to balk or backup in a race. The author has also observed that these more vocal pigs are often prone to high levels of PSE. A plant that has a high percentage of overly vocal animals can still use vocalization scoring to monitor handling quality within their own plant. Plants that audit vocalization on a regular basis have found that it is a simple measure that has helped them to maintain quiet careful handling. Auditors must also be observant to insure that a condition doe not exist which could prevent an animal from vocalizing. If a plant restrains sensible animals by paralyzing them with an electric current, they may not be able to vocalize. Immobilization with electricity is highly aversive to animals and detrimental to their welfare (Grandin et al., 1986; Pascoe 1986, Lambooy, 1985). The use of electricity to immobilize a sensible animal would make vocalization scoring impossible. It is the author’s opinion that for welfare reasons, electrical immobilization conscious animals should be prohibited.

The author also has developed a simple squeal scoring system for pork slaughter plants (Grandin, 2000a). The percentage of time that the entire stunning area is quiet is calculated by counting the number of stunner cycles were all the pigs were quiet. As each pig is stunned, the auditor checks yes “heard a squeal” or no “room quiet.” Large plants which have worked hard to reduce electric prod usage have been able to achieve percentages of 52% and 80% of the time quiet. Prior to working on improving handling the percentage of time that the room was quiet was 0 to 5%.

Audit on a Regular Basis

To maintain a high level of quality in handling audits must be done on a regular basis. During 1999 there has been a tremendous improvement in stunning and handling compared to data collected in 1996 (Grandin 2000b). This is due to audits of handling and stunning conducted by McDonald’s Corporation. By the end of 1999, 42 beef plants and 19 pork plants were audited. Ninety percent of the beef plants at the end of 1999 were able to stun 95% of the cattle with one shot compared to only 30% in 1996. Thirty-seven percent (15 plants) stunned 99% to 100% with one shot. In 1999 only one beef plant (10%) was able to do this. If the first shot was missed cattle were immediately restunned. A plant received a failing score if a sensible animal was hung in the bleed rail. The percentage of cattle vocalizing was also reduced in 1999. In the 1996 USDA survey, 10% of the cattle surveyed vocalized during handling (Grandin, 2000a). In the 1999 McDonald’s audits the percentage of cattle that vocalized in 42 plants dropped to an average of 2.7%.

There are two factors that account for the big improvement, being held accountable for their practices by a major customer and the requirement to do self-audits. Many plants do regular self-audits and send them into the McDonald’s system. After all, one manages the things that they measure. Data coming in from the year 2000 McDonalds and Wendy’s audits indicates that plants that conduct regular self-audits have maintained their handling quality. Continuous measurement is essential and plants that do not do self-audits have slipped in performance

Measuring handling quality in squeeze chutes

The same type of auditing system can also be used to monitor handling practices in feedlots, farms and ranches. Three simple measures can be used for auditing handling in squeeze chutes. They are percentage of cattle that vocalize during handling, percentage of cattle electric prodded and the percentage that walk into and out of the squeeze chute. Cattle that walk quiet into a squeeze chute are less likely to become injured and they struggle less. The author has observed that sometimes a slightly higher percentage of cattle will vocalize during eartagging or implanting compared to a slaughter plant. However, the percentage that vocalize during movement though the single file chute and catching in the squeeze chute can easily be kept at 3% or less.

The author has conducted cattle handling demonstrations at about 20 feedlots. An easily achievable electric prod use percentage is 1% of the cattle prodded. It is important to get the electric prod out of people’s hands. A flag on a paddle stick should be the primary driving tool for the handler to carry. The electric prod should remain on the vaccine table and only be picked up and used on an animal that refuses to enter the squeeze chute.

Electronic Auditing

Electronic measurement of handling quality can be easily done. Burrows and Dillon (1997) used a police radar unit which is used to catch speeding cars to monitor the speed that cattle left a squeeze chute. Animals that ran out of the squeeze chute at a high speed gained weight more slowly. Schwartzkoph-Genswein et al. (1998) instrumented a squeeze chute to measure how hard cattle hit the headgate and how much an animal shook the chute. Their instruments measured fluctuating signals from the electronic scale under the squeeze chute. They also installed strain gauges on the headgate to measure the force of cattle hitting the headgate. It would be easy to correlate headgate force measurements and shaking measurements with weight gain, dark cutters, injection site damage, sickness and implant quality. The advantage of electronic measurement is that it would provide continuous feedback on handling quality.

Individual cattle IDs which were tracked with a computer make it possible to document losses caused by poor handling. Will Pace. Agrinfolink presented data at the National Institute of Animal Agriculture meeting that indicated that cattle transported by one driver consistently had 1.5% more weight loss. It is likely that rough handling or poor driving may have contributed to this loss. Instrumenting a truck to electronically record the incidence of rapid breaking and guide acceleration could be easily done to trace weight. Sudden movements of a truck can throw cattle off balance. Pace (2000) also reported that 80% of consumer complaints about tough beef could be traced back to one producer who had wild cattle.

Financial Incentives and Handling Quality

When people are held accountable for losses, they will take steps to stop them. When losses can be passed on to the next market segment, there is no financial incentives to reduce losses. For example, cattle sold live weight had twice as many bruises compared to cattle cold on the rail (Grandin, 1981). The feedlot manager had an incentive to reduce bruises when he had to pay for them. Horned and tipped cattle will have significantly more bruises (Shaw et al., 1976 and Wythes et al., 1979). A rancher has no incentive to dehorn newborn calves if he/she does not receive a premium price for hornless animals.

Systems of financial incentive must have accurate measurements of losses. Without continuous measurements an incentive system will not work. The author has observed that handling improved when companies became vertically integrated. However, this improvement will only take place if accurate information on losses from bruises, PSE, dark cutters or injection site damages is communicated throughout the system. Computerized systems for tracking losses and individual electronic or bar code identification of animals will facilitate monitoring of losses. Changes will not occur until the measuring tools are in place.

The author has observed that paying feedlot processing crews on a piece work basis encourages rough, careless handling and sloppy administration of injections. Feedlot processing crews should be given financial rewards for doing their jobs correctly. However, the variables being measured must be chosen carefully. For example, if a crew is paid solely on the quality of growth promotant implant administration in the ear, they may be tempted to squeeze the cattle excessively in the hydraulic squeeze chute or use devices to hold the head that will interfere with proper injection technique.

Solving Animal Balking Problems

If animals constantly balk and refuse to move, it will be almost impossible to reduce electric prod use and handle them quietly. Lighting problems can slow down animal movement. Cattle and pigs will often balk and refuse to enter a dark place (Van Putten and Elshof, 1978; Grandin 1996). In one beef slaughter plant, adding a light at the entrance of a dark conveyor restrainer reduced balking and the need for an electric prod. The percentage of cattle that vocalized dropped from 8% to 0% after the light was installed (Grandin, 2000b). For more information on solving lighting problems, refer to Grandin (1998c and 1996). In about 20% of cattle feedyards the author has observed that it was often difficult to reduce electric prod use. This often occurred when the handling facility was located inside a dark building. It was especially a problem on a bright sunny days. Opening up all the doors or installing white translucent plastic side panels or skylights will often improve cattle movement by letting more light into the building. In slaughter plants air drafts blowing into the faces of approaching animals may make them balk and back up.

Moving objects such as a loose dangling chain end, seeing moving people up ahead and flapping objects should be removed. They attract the animal’s attention and it may balk and refuse to move. Animals notice small visual details that most people ignore. Shiny sparkling reflections off shiny metal or wet floors can also cause balking. Moving a ceiling lamp to eliminate a shiny reflection will also reduce balking. To have really quiet handling, all the little distractions that cause balking must be removed (Grandin 1996-1998e).

Working with Squeeze Chutes

Well designed facilities, curved chutes and round crowd pens will facilitate the movement of animals. Design information can be found in Grandin (1990, 1997d, 1998d, 2000a). The single file chute that leads to the squeeze chute and the sides of the squeeze chute should be solid. Angled rubber louvers mounted on the side drop down bars are recommended on the squeeze chutes. These louvres prevent the cattle from seeing people when they enter the squeeze chute. However the side drop down bar with the attached louver can be opened for access to the animal’s body.

On most squeeze chutes, the author recommends removal of long neck extender bars from the headgate to provide access to the neck for injections. If cattle are handled quietly before they get up to the squeeze chute, they can be easily backed up in the headgate to make their necks easily accessible for injections. Backing the animal up in the headgate will also hold its head still for ear implants. Some squeeze chute operators will deliberately catch the animal’s jaw in the neck extender bars. They do this to get the neck in an accessible position for injections. This will result in 50% or more of the cattle vocalizing. Catching the jaw can also injure the animal’s jaw or make it sore. Animal’s that have been hit on the head by either the neck extender bars or the headgate remember the aversive experience and will often balk and refuse to enter a squeeze chute again in the future. It is also likely that hitting the animal’s jaw may cause pain which may inhibit feed consumption. Cattle that walk quietly into a squeeze chute can be easily caught right behind the jaw with a headgate that does not have neck extender bars. The head will be held still for implanting and the neck will be accessible at the first drop down bar for injections.

Cattle that walk quietly into a squeeze chute are also less likely to get severe shoulder injuries. Some squeeze chutes have a spring loaded headgate to absorb the shock of an animal hitting it. On a hydraulic chute, the pressure must be set correctly to avoid injuries. Cattle should be able to stand in a squeeze chute without straining, grunting or vocalizing. The pressure relief valves should be set so that the squeeze chute will automatically stop squeezing at a reasonable pressure. When cattle are calm, less pressure will be required to hold them.

Behavioral Principles of Handling

Handlers must also be trained in the behavioral principles of cattle handling. More information on behavioral principles of handling refer to Grandin (2000a, 1987 and 1995 and Smith, 1998). Handlers of both cattle and pigs need to understand the animal’s flight zone and point of balance. Some other handling tips are: fill the crowd pen that leads up to the single file chute half full, move small bunches and avoid yelling and whistling. Waynert et al. (1999) found that yelling and whistling had a greater effect on the heartrate of cattle than the sound of a gate slamming. Lanier et al., (2000) found that cattle with an excitable temperament were more sensitive to intermittent high pitched sounds and rapid movement, than cattle with a calmer temperament.

Accustom Animals to Handling

Both pigs and cattle will move more quietly during handling if they have become accustomed to people walking through their pen or pasture before the arrive at a slaughter plant. This is especially important for animals from certain genetic lines which tend to be more excitable. Feedlot and slaughter plant managers have reported that wild, excitable cattle are difficult to handle and they have more dark cutters. The author has observed that excitable genetic lines of cattle are more likely to become highly agitated at a slaughter plant if they had been handled exclusively by people on horse back prior to arrival. They become agitated when they first see a person on foot because they had never been handled by a person on foot on the feedlot or ranch. Burrows and Dillon (1997) suggest that training and getting cattle accustomed to handling is most important for cattle with excitable temperaments. Binstead (1977), Fordyce et al. (1985-88) and Fordyce (1987) all report that training young bos indicus heifers produced calm adult cows which were easier to handle. The problem with animals with excitable genetics is that they are more reactive to sudden novel new experiences (Grandin and Deesing, 1998). Ranchers have reported that an animal may be calm at the home ranch and then become highly agitated in an auction ring or at a feedlot.

Practical experience in large pork slaughter plants indicate that certain genetic lines of lean hybrid pigs are easier to drive and less likely to pile up and squeal during handling if a person has walked through their pen every day during finishing. Experiences prior to slaughter will affect ease of handling. Contact with people in these pens will produce less excitable pigs (Grandin, 1987 and Grandin et al., 1986). Geverink et al. (1998) and Abbot et al. (1997) both report that moving pigs out of their finishing pens produces animal that are easier to drive.

To provide good meat quality, an animal that is reasonably easy to drive and move must be presented to the slaughter plant.

Welfare Issues

Increasing public concern about animal welfare is a major reason why major restaurant companies and supermarkets are auditing handling and stunning practices in both the U.S. and abroad. Many of the poor handling practices discussed in this paper must be corrected to improve welfare. Hitting cattle hard on the jaw with the neck extender bars on a squeeze chute headgate or repeated shocking of animals with electric prods are practices that the public would not find acceptable. They also need to be corrected because it is the right thing to do.


Regular measurement and auditing of animal handling will help maintain the quality of handling. People manager the things that they measure. The author has observed that auditing of handling quality on a regular basis will prevent handlers from slipping back into old rough habits. Quiet handling of both pigs and cattle will help preserve meat quality by reducing injection site damage, dark cutters, PSE, bruises and bloodsplash.


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