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I have worked as a consultant to themeat industry since the early1970s. I’ve been in more than 300

slaughter plants in the United States,Canada, Mexico, Europe, Australia,New Zealand, and South America.During the course of my career, I’veseen many changes take place, butI’m going to focus in this paper on mywork to improve conditions for theslaughter of cattle and calves andlater address transport and other ani-mal-handling issues.

The U.S. Humane Slaughter Act,passed in 1958, required that all meatsold to the federal government had tocome from animals that had beenhumanely slaughtered. Use of thepole axe to render animals uncon-scious and the bleeding of fully con-scious pigs were replaced by use ofthe captive bolt stunning pistol incattle and administration of eithercarbon dioxide (CO2) or electricalstunning for pigs. This change was amajor step forward, since scientificstudies show that both electricalstunning and captive bolt stunningwill instantly render animals insensi-ble to pain (see reviews by Grandin1994, 1985/86; Eikelenboom 1983;UFAW 1987; Gregory 1998).

Unfortunately, however, CO2-induced stunning is not instanta-neous, and there has been controversywithin the scientific community overwhether animals have an adverse

reaction to CO2 gas. Some studiesshow evidence of aversion; others donot (Forslid 1987; Grandin 1988a;Dodman 1977; Raj et al. 1997). Myown observations lead me to believethat some pigs can be anesthetizedpeacefully with CO2 while others fran-tically attempt to escape when theyfirst smell the gas (Grandin 1988a).Genetic factors appear to influencethe reaction. Purebred Yorkshire pigsare anesthetized peacefully (Forslid1987), for example, while otherstrains become agitated prior tobeing anesthetized (Grandin 1988a;Dodman 1977). Jongman et al.(2000) found that for Landrace–Large White crossbreeds breathingeither 60 percent or 90 percentCO2 was less aversive than a shockfrom an electric prod. CO2, it may be noted, causes highly variable reac-tions in people. It causes anxiety insome and has little effect on others(Perna et al. 1994; Biber et al. 1999;Perna et al. 1996). It is my opinionthat CO2 is suitable for some genetictypes of pigs but causes problemswith other genetic types. CO2 experi-ments should be conducted withstress-susceptible pigs, in particular.The potential of other gases, such asargon, for use in stunning is also wor-thy of investigation.

In 1978 the Humane Slaughter Actwas amended to cover all federallyinspected plants. (Federal inspection

allows a plant to engage in interstatecommerce, regardless of who thebuyer is.) The act was also extendedto cover the handling of animals priorto slaughter while they were on thepremises of the slaughter plant. Cruelpractices such as dragging conscious,crippled, non-ambulatory (downed)animals were prohibited. However,the handling of animals for ritualslaughter was—and is—exempt, as isthe slaughter of poultry. In ritualslaughter, both kosher (Jewish) andhalal (Muslim), the throat of anunstunned animal is cut.

My First ProjectMy career started at the Swift FreshMeats plant in Tolleson, Arizona, in1973. The plant manager allowed meto visit every week so I could learn theindustry. Nobody knew who I was andno attempt was made by the plantemployees to be on “good behavior”while I was there.

The equipment available was ofpoor quality, but at a line speed of165 cattle per hour, most animalswere stunned correctly with one shotfrom a captive bolt pistol. Swift had astunning box that consisted of a long,narrow stall in which three cattle at atime were loaded. If the animalsbecame agitated while in the box,they jumped on top of each other.Another problem was that slaughter

Progress in LivestockHandling andSlaughter Techniquesin the United States,1970–2000

Temple Grandin

6CHAPTER

plants were heavily unionized, andunion work rules made it very diffi-cult to discipline any employees whodeliberately abused the cattle.

In 1974 I worked on my first equip-ment project, replacing the stunningbox at the Swift plant with a newdevice, a V conveyor restrainer. Thissystem, a larger version of a systemalready in use for the slaughter ofpigs (Regensberger 1940), had beenconstructed in the early 1970s byOscar Schmidt of Cincinnati Butch-er’s Supply Company and DonWillems of Armour Company. The ani-mals rode along supported by twoconveyors. Compared to the old mul-tiple-animal stunning box, it was agreat improvement. The V conveyor

system was safer for plant employeesand much less stressful for the cattle.The one the plant engineer at Swiftand I installed was the third V con-veyor restrainer system in the UnitedStates. By 1980 the V conveyorrestrainer had replaced many of thedreadful old stunning boxes that hadheld several panicked cattle at a time.(Today, stunning boxes are used main-ly in small plants; those that hold onlyone animal work very well in such cir-cumstances, provided they have non-slip floors.)

KosherSlaughter in the 1970sLate in the 1970s, I had the opportu-nity to observe kosher slaughter atSpencer Foods, the world’s largestkosher slaughter plant. Cattle weigh-ing 1,200 pounds each were hoistedoff the floor by one back leg, and anose tong attached to a powerful aircylinder was used to stretch theirneck so that the schochet, a rabbiwho performs kosher slaughtering,could make the throat cut. I was hor-rified at the sight and sounds of bel-lowing, thrashing beasts. Workerswore football helmets to protect theirheads from the animals’ flailing fronthooves. I could even hear the cattlebellowing from the plant’s office andparking lot. I vowed I would design asystem to restrain the cattle in amore comfortable upright position.Many of the smaller kosher slaughterplants that slaughtered large cattleused a holding box called the ASPCApen (Marshall 1963) (Figure 1). TheAmerican Society for the Preventionof Cruelty to Animals (ASPCA) hadbought the patents on the box in the1960s so that any plant could use thebox royalty free. Spencer Foodsslaughtered 150 cattle per hour, andit would have had to buy two ASPCApens—and construct a building addi-tion—to accommodate this volume oftraffic. Since pre-slaughter handlingfor kosher slaughter was exempt fromthe Humane Slaughter Act, shacklingand hoisting fully conscious cattlewas an economical alternative.

I proposed to plant managementthe idea of building a head-holdingdevice on the V conveyor restrainer.(It is completely described in Grandin1980a.) I worked with Spencer to helpdesign the system, which involved nostructural alterations to the buildingalready in use. For the large kosherplant, it was a great improvement overshackling and hoisting.

The next big improvement in equipment was the development ofupright restraint devices for kosher-

To reduce stress on the animal, the belly lift should not lift the animal off the floor. Allparts of the apparatus that press against the animal should be equipped with pressure-limiting devices and move with a slow, steady, smooth motion.

102 The State of the Animals: 2001

Progress in Livestock Handling and Slaughter Techniques in the United States, 1970—2000 103

slaughtered calves and sheep. TheCouncil for Livestock Protection(CLP)—a consortium of The HumaneSociety of the United States, Ameri-can Humane Association, The Fundfor Animals, Massachusetts Societyfor the Prevention of Cruelty to Ani-mals, and others—funded research atthe University of Connecticut todevelop a system for holding calvesand sheep in an upright position forkosher slaughter. At that time theonly piece of equipment available forholding an animal in an upright posi-tion was the ASPCA pen for adult cat-tle. A restraint device was needed toreplace the shackling and hoisting ofcalves and sheep. A laboratory proto-type was completed during the early1970s (Giger et al. 1977; Westerveltet al. 1976). Stress research conduct-ed at the University of Connecticutdemonstrated that having an animalstraddle a moving conveyor was a low-stress method of restraint. The labo-ratory prototype was a major innova-tion, but many more components hadto be developed to make a commer-cially viable system. Since no slaugh-ter plant was interested in imple-menting the design, the prototypewas put in an old sheep barn.

The 1980s and the KosherCalf ProjectDuring the early 1980s, plant linespeeds increased and the labor unionswere no longer so powerful. The oldSwift and Armour plants, which hademployed union labor, were closed.They could no longer compete withnew companies that paid lower wagesand had fewer restrictive work rules.The emphasis was now on speed,speed, and more speed. In some largeplants, stunning practices actuallyworsened compared to conditions inthe 1970s. Crews were reduced insize, and cattle were being handled ata rate of 250 per hour. It was a badtime for both the animals and themeat industry.

During that decade I completed two

major projects. The first was thedesign for a curved chute and V con-veyor system for Moyer Packing. Thesecond one was the completion of theproject that the University of Con-necticut had started ten years earlier.Curved chute systems were an impor-tant innovation for handling cattlebecause cattle move more easilyaround a curve (Figure 2). (These sys-tems are described in Grandin1980b,c, 1987, 1998c, 2000a.)Curved chutes with solid sides, in par-ticular, facilitate cattle movementbecause they take advantage of cat-tle’s natural tendency to want toreturn to where they came from. Thechute’s solid sides and curves preventcattle from seeing moving people andequipment ahead of them in theslaughter facility so the animals areless likely to react to the sight byattempting to go backward.

In 1986 the CLP asked me todesign and install the University ofConnecticut system in a veal calfplant, Utica Veal. We rescued the ply-wood prototype, which was practicallyon its way to the landfill, and addedseveral other components to make itwork commercially (Grandin 1988b).One was a new entrance design that

positioned the calves’ legs on eachside of the moving conveyor. For thefirst time, equipment was available toreplace shackling and hoisting ofkosher calves and sheep. The new sys-tem was later installed in two otherveal plants.

The 1990s and BehavioralPrinciplesBy the end of 1999, half of all the cat-tle in the United States and Canadawere being handled in systems I haddesigned for slaughter plants. I hadreceived a grant to make a large-cat-tle version of the conveyor system atUtica Veal (Grandin 1991, 2000a)(Figure 3). Cattle entered it moreeasily and rode more quietly thanthey had in the V conveyor restrainer.One challenge was that adult cattleare wilder and more difficult to han-dle than are tame veal calves. Thefirst time the restrainer was run atthe Excel plant in Schyler, Nebraska,the cattle refused to enter and theydid not ride quietly as had the tamecalves at Utica Veal. Two very simplechanges solved the problem, and

Figure 2. Cattle stay calmer because they cannot see the handler on the ramp when they first enterthe chute. A curved chute also takes advantage of the natural tendency of cattle to want tohead back to where they came from.


their success showed the power ofusing behavior modification, insteadof force, to handle cattle. Bothchanges calmed the cattle by control-ling what they could see.

First, I installed a false floor madeof the conveyor belting. Since therestrainer conveyor was seven feet offthe floor, the entering cattle had beengreeted by a “visual cliff” effect.Ruminants such as cattle and sheepcan perceive depth (Lemman and Pat-terson 1964). The belting under theconveyor provided the animals withthe illusion of a solid floor to walk on(Grandin 1991, 2000a).

The second change was even easier.A piece of cardboard positioned sixinches above the animals’ backsblocked the animals’ vision straightahead. The cardboard was replacedwith metal, and the system workedperfectly. Twenty-five of these center-track restrainer systems are now inuse around the world.

Although the center-track conveyorrestrainer was rapidly adopted by theindustry, one of my biggest frustra-tions has been getting people to fullyunderstand the power of using behav-ioral principles to handle animals.Equipment companies have oftentried to “improve” the restrainer by

removing parts they perceive asunnecessary. They have not been ableto understand why a piece of metalthat blocked the animal’s vision wasso important.

At one plant I visited recently, cat-tle were balking, refusing to enter therestrainer or not riding quietly. Theequipment company had left out thefalse floor and had shortened thepiece of metal that blocked the ani-mals’ vision. It had also added ahydraulic cylinder to forcibly pushrearing cattle down, thinking thatthis was an improvement! I had themaintenance shop build a false floorand add more metal sheeting to blockthe cattle’s vision. After these partswere installed, the cattle rode calmly.A two-foot difference in a piece ofmetal was the difference betweencalm and agitated cattle.

KosherSlaughter in the 1990sBetween 1993 and 1995, several largeshackle-hoist systems were ripped outand replaced with either ASPCA pensor a center-track restrainer system.

I designed a new head-holding devicefor the center-track restrainer (Figure4). The new design was a greatimprovement over the system atSpencer Foods. The new head holderwas very similar to the one on anASPCA pen. It was mounted on twosliding doors, and the two halves ofthe chin lift slid apart sideways(Grandin 2000a).

Employee safety was a major reasoncorporations sought to eliminateshackling and hoisting of fully con-scious cattle. Another was HenrySpira, a well-known animal activist,who wrote letters pointing out themethod’s shortcomings to severalcorporations still using it. Today 90percent of the kosher-slaughtered cat-tle in the United States are held in anupright restraint system. (Unfortu-nately, about half the kosher vealcalves and most of the kosher sheepin the United States are still shackledand hoisted prior to the throat cut.)In Europe, Canada, and Australia,upright restraint is now required forall animals. However, countries suchas Uruguay and Guatemala still useshackling and hoisting techniques.Both export meat to Israel and theUnited States.

From an animal welfare perspec-

The cattle ride along on the moving conveyor. Design details are very important. Cattle remain calmer if the solid hold-down rack islong enough to block the animals’ vision until they are completely off the entrance ramp. The solid false floor prevents cattle fromseeing a steep drop-off under the conveyor. In a well-designed system that has proper lighting, 95 percent of the cattle will enter without the use of an electric prod.


tive, the variables of kosher slaugh-ter—the throat cut and the methodof restraint—must be evaluated sepa-rately. When conscious animals areshackled and hoisted, it is impossibleto observe the reaction to the throatcut itself because the suspended ani-mal is fighting the highly stressfulrestraint. Once I had built a restraintdevice that would hold the animalgently, it became possible to observethe reactions to the throat cut, orshechita. When the cut is made cor-rectly, the animal appears not to feelit (Grandin 1994, 1992; Grandin andRegenstein 1994). When the headholder was loose enough for the ani-mal to move it, the animal did notmove at all when the cut was per-formed correctly.

From my work with kosher restraintdevices, I developed four behavior-based principles of restraint. Theyare: 1) the animal’s vision should beblocked so that the animal does notsee people and other moving objects;the view of a pathway for escapeshould also be blocked until the ani-mal is fully restrained; 2) optimalpressure of holding machinery shouldnot be too tight or too loose, otherwisethe animal will struggle; 3) equipmentshould operate with a slow, steadymovement; sudden jerky motionscares the animal; and 4) the fear-of-falling righting reflex should not be trig-gered; the restrainer must either fullysupport an animal or have non-slipfooting (Grandin 2000a, 1994).

How Stressful is Slaughter?Literature shows equivalent levels ofcortisol, a stress hormone, in animalshandled at slaughter plants and inanimals restrained for vaccinationson the farm. Walking through thechutes at a slaughter plant doescause some stress, but it is similar tothat of on-farm restraint and han-dling (Grandin 1997a reviewed Lay et al. 1992; Crookshank et al. 1979;Ray et al. 1972; Zavy et al. 1992;Mitchell et al. 1988; Ewbank et al.1992; Dunn 1990; Cockram andCorley 1991; Tume and Shaw 1992.)The cortisol range for both on-farmhandling and cattle slaughter was 24to 63 ng/mL. The one exception wasa kosher plant that inverted cattle ontheir backs for 103 seconds; thoseanimals had 93 ng/mL (Dunn 1990).

Current CattleIndustryProblemsAt the beginning of my career, Ithought I could fix all plant problemswith better engineering. I do notbelieve this today! By the 1990s themeat industry had cattle handlingequipment that was vastly superior tothe equipment in the old Swift plant,but good equipment and engineeringare only one-third of the equation.Good management and well-trainedemployees make up the other two-thirds. Good equipment provides thetools that make good handling easier,but it is useless without good man-agement. In a few poorly managedplants, some of the worst acts of cru-elty I have witnessed happened withequipment I designed. In these cases,employees were completely unsuper-vised. For most of my career, I workedwith the meat industry primarily as adesigner and supervisor of equipmentinstallation, so I was able to witness“normal” employee behavior.

In the mid-1990s, cattle stunningwas a definite problem. In 1996 only

(A) Bi-parting sliding doors with the two halves of the chin lift mounted on them.(B) Forehead bracket slides up and down. A three-inch-diameter pipe fits behind theanimal’s poll. (C) A chin-lift yoke raises the head. The chin lift pivots on the slidingdoors. (D) The conveyor on which the animal is riding is stopped.

30 percent of the plants stunned 95percent of their cattle correctly—with one shot (Grandin 1997a,b).Cattle were re-stunned prior to bleed-ing. (Pig stunning was much better,with 90 percent of the plants stun-ning pigs correctly. Eisnitz [1997]did describe horrific conditions intwo terrible plants, where pigs werescalded alive and cattle were skinnedalive. I have observed many abuses,such as broken stun guns, the drag-ging of downed, crippled animals, anddeliberately driving animals over thetop of a downed animal; but in thevast majority of plants, I have neverobserved live pigs going into thescalder or live cattle being dismem-bered. When a live pig is scalded, theUSDA will usually condemn the car-cass as unfit because water has beenaspirated into the lungs. This pro-vides an economic incentive to stunand bleed pigs properly.)

People often mistakenly equatereflexive kicking with animal con-sciousness. Grandin (1994) and Gre-gory (1998) explain how to assessinsensibility. The beef plant describedby Eisnitz (1997) was a small plantwhere the same employee who bledthe animal also skinned the head.Doing something terrible like skin-ning a live head is more likely tooccur in a small plant where the sameperson performs both bleeding andthe initial stages of skinning. In alarge plant, stunned and bled cattlecarcasses suspended by one rear legare moved along a power chain. Thefirst part of the animal skinned afterbleeding is the free rear leg. Skinninga “live” leg is very dangerous becauseit will kick the worker in the face. Theemployees who do “legging,” there-fore, put a lot of pressure on the stun-ner operator and bleeder to makesure cattle are dead before they reachthe legging stand. (It should benoted, however, that supervisors alsoput pressure on stunner operators tokeep the line moving rapidly, so oper-ators may not always be so carefulabout making sure that the animalsare stunned properly.)

EmployeePsychologyI have observed hundreds of peopleworking in slaughter plants. They fallinto three basic psychology types: 1)box stapler 2) sacred ritual 3) sadist(Grandin 1988c). The vast majority ofthe employees who stun cattlebecome “box staplers.” They do theirjob as if they were stapling boxes onan assembly line. They will seldomengage in deliberate cruelty. Rabbiswho perform kosher slaughter view itas a religious ritual and they concen-trate on their work within that con-text. Unfortunately, there are a fewpeople who become sadists, and man-agement should remove them fromcontact with animals.

The well-managed plant has a man-ager or quality-control person whoacts as a “conscience” to controlbehavior. In a poorly managed plant,employees may become rough unlesssomeone in authority controls theirbehavior. It is important not to over-work employees who handle or stunanimals. Bad behavior is more likelyto occur if the employee is over-whelmed or if equipment is in need ofrepair. For good conditions, animal-handling and -stunning jobs must notbe understaffed.

I have observed that many plantswill have good management and goodhandling in the stockyards, but super-vision in the stunning area will bepoor. This trend was very evident inmy USDA survey (Grandin 1997a,b).People who are too close to killing allthe time become callous. The personwho supervises employee behavior inthe stunning area must be involvedenough in the day-to-day operationsto care about the process, but not so involved that he/she becomes cal-lous and indifferent to suffering. (Inmy USDA survey, the two worst-behaved employees were kill fore-men.) The supervisor must have theauthority to discipline employees whoabuse animals.

A Major ChangeI saw more improvement in both han-dling and stunning from 1997 to1999 than I had seen previously in myentire career. Two fast-food compa-nies started auditing U.S. plants dur-ing 1999 to make sure they compliedwith the American Meat InstituteGuidelines (Grandin 1997c). Bothfederally inspected beef and porkplants were scored objectively. Manyplants now have better stunner main-tenance, and electric prod usage hasbeen greatly reduced. One companyaudited forty-one beef plants in 1999;I was present at about half of theaudits. By end of 1999, 90 percent ofbeef plants were stunning 95 percentof the cattle they processed with oneshot; 37 percent were stunning 99percent to 100 percent with one shot(Grandin 2000b). If the first shotmissed, the animal was immediatelyrestunned. (This was a big improve-ment over performance noted in the 1996 USDA survey [Grandin1997a,b].) Large flags were beingused to move pigs, and a piece of plas-tic on a stick was being used to movecattle. These devices had replacedmany electric prods.

In beef production, plants werescored on percentage of cattlestunned with one shot, insensibilityon the bleed rail, and vocalizationduring handling. Vocalization (moosand bellows) is a sensitive indicator of welfare-related problems such asexcessive electric prod use, slippingand falling, missed stunner shots, andexcessive pressure from a restraintdevice (Grandin 1998a,b).

Researchers have found that vocal-ization in both cattle and pigs is cor-related with physiological indicatorsof stress (Dunn 1990; Warriss et al.1994; White et al. 1995). Vocalizationis also correlated with pain (Wattsand Stookey 1998; Weary 1998).Vocalization scoring can pinpointhandling problems. Beef plants withgood handling practices will have 3percent or less of their cattle vocaliz-ing during handling in the stunningchute (Grandin 1998b). (To keepscoring simple, vocalization is scored



on a “yes” and “no” basis—a coweither vocalizes or it does not. Vocal-ization in the yards where cattle arestanding undisturbed is not scored.)In 1999 74 percent of forty-two U.S.beef plants had vocalization scoresof 3 percent or less for cattle. In 1996only 43 percent of the plants had avocalization score of 3 percent or less.Excessive electric prod use, due tocattle balking, had raised vocalizationscores to as high as 17 percent atsome plants.

Vocalization scoring can be used tochart handling improvement within aplant. It also works well on feedlotsand ranches. Vocalization scores willoften be higher than 3 percent whenanimals are ear-tagged on ranches orfeedlots. In contrast, it is easy to havea 0 percent vocalization rate for ani-mals moving through the chutes,being restrained in the squeezechute, and being vaccinated.

The presence of distractions, whichmakes cattle balk, makes a 3 percentor less vocalization score almostimpossible. The movement of a small chain hanging in a chute, forexample, will make an approachinganimal stop and impede the flow of the other animals. Lighting a darkrestrainer entrance will often improveanimal movement. (Information ondebugging systems and removing

distractions can be found in Grandin1998c, 1996.)

People manage the things thatthey measure. Bad practices become“normal” if there is no standard towhich they can be compared. Vocal-ization scoring can be used to chartprogress as a plant improves itsequipment and practices. Table 1shows vocalization scored from sevenaudits of 100 cattle each in a singleplant. These audits took place over aperiod of several months.

Dairy and PigIndustryProblemsThe number-one transport problem in the 1970s—and the number-onetransport problem today—is loadingonto a truck animals who are not fitfor transport. The dairy industry hassome of the worst such problems.Baby dairy calves, who are too youngto walk, are not fit for transport. Ema-ciated or lame dairy cows are not fitfor transport. Downer dairy cows,those who are unable to walk, aremore prevalent now than in 1994.Numbers of beef cattle downers havedecreased slightly (Smith et al. 1994,1995; Roeber 2001). The 1999 audit

by Smith et al. indicated that 1.5 per-cent of all culled dairy cows arrived ata slaughter plant down and unable towalk. In the beef industry, 0.77 per-cent of the cows were downers.

In the past thirty years, althoughthe handling of beef cattle on ranch-es and feedlots has improved, welfareproblems in the transport of old,culled dairy cows have worsened.Genetics is partly to blame. Selectionof individuals for milk production hasincreased the incidence of lameness.John Webster at Bristol University inthe United Kingdom states that thetypical cow’s foot can no longer sup-port its weight. A dairy veterinarian inFlorida told me that the incidenceand aspects of lameness in dairy cowsare horrendous. Leg conformation isheritable, and good conformation willhelp prevent lameness (Boettcher etal. 1998; Van Dorp et al. 1998).Slaughter plant managers and truckdrivers have reported that dairies thatuse bovine somatrophin (BST), bovinegrowth hormone, in their dairy herdssometimes have more thin, weakcows. Administration of BST reducedbody condition score (Jordan et al.1991; and West et al. 1990). Unlessthe cow is fed very well, it may losebody condition. The degree of bodycondition reduction is related to thedose of BST.

Table 1Improvements in Vocalization Percentages in a Cow SlaughterPlant When Practices and Equipment Were Changed

Audits Vocalization (percentages) Practices and Equipment

1 17 V conveyor restrainer—cows balked at the restrainer entrance and excessive use of electric prod caused vocalization

2 14 No changes in model

3 7 Employee training on reducing prod usage

4 10 Continued working with employees

5 9 Continued working with employees

6 5 Removed V conveyor restrainer and replaced center-track conveyor

7 2 Improved lighting, installed false floor and sheet metal to block the cattle’s vision (these had been leftout because the equipment installer did not believe they were important)

Single-trait selection of pigs forrapid growth and leanness has creat-ed pigs who are more fragile and like-ly to die during transport. I haveobserved that death losses duringtransport have tripled in the 1990scompared to the 1980s. Some hybridpigs are very excitable, which makeshandling them more difficult(Grandin 2000a). These pigs act asthough they have high sympatheticnervous system arousal. A tap on therump will make them squeal. Normalpigs are much less likely to startle.Pigs who are selected solely for pro-ductivity may have a loss of diseaseresistance. Genetic factors affect sus-ceptibility to disease.

One of my biggest concerns is thepossibility that producers are pushinganimals beyond their biological lim-its. The pig industry, for example, hasrepeated most of the mistakes thatthe broiler-chicken industry made.Genetic traits are linked in unexpect-ed ways. Some pigs grow so fast thatthey have very weak bones. These pigshave large bulging muscles but are sofragile that livestock insurance com-panies will not sell transport insur-ance to producers to cover them. For-tunately, some breeders are nowselecting for more “moderate” pigs,which will have fewer problems.

GoodStockmanshipPaysGood stockmanship can improve pro-ductivity of pigs and dairy cattle bymore than 10 percent (Hemsworth1998; Rushen et al. 1999). Animalswho are fearful around their caretak-ers are less productive. They experi-ence lower weight gain and lowermilk production. Pigs have fewerpiglets. At the highest-producingdairy in Colorado, the cows are verytame and approach people for pet-ting. Good stockmanship costs verylittle. Feedlots that handle cattle gen-tly find that the animals go back ontotheir feed more quickly than thosewho aren’t handled gently. One feed-

lot that handled cattle roughly in thesqueeze chute recorded a 16 percentdrop in feed consumption the follow-ing day.

If good stockmanship could be pur-chased, everybody would buy it imme-diately. I have observed that peoplebuy twice as many books on corraldesign as videos on low-stress cattlehandling and stockmanship princi-ples. They would rather buy equip-ment than change their behavior. Tobe a really good stockman, one has to change one’s attitude toward theanimals. Animals can no longer beviewed simply as economic units.

I have observed that when peopleon farms and in feedlots and meatplants start handling animals moregently, their attitudes toward theanimals change. In 1999 when onecompany’s audits started, manyworkers at the company’s plantsreplaced electric prods with otherdriving aids such as flags. I noticedthat the employees’ manner towardsthe animals changed. Instead ofaggressively poking at animals withan electric prod, they patted themgently on the rear. Changing theworker’s actions helps to change theworker’s attitudes.

ConclusionsPromoting better stockmanship isessential to improving animal welfare.Large meat-buying customers such asfast-food restaurants in the UnitedStates and supermarket chains in theUnited Kingdom can motivate greatchange by insisting that suppliersuphold better animal welfare stan-dards. The greatest advances of thelast thirty years have been the resultof company audits. To maintain suchprogress, handling and stunning mustbe continually audited, measured,and managed. Handlers tend to revertto rough handling unless they aremonitored and managed. An objec-tive scoring system provides a stan-dard that can be upheld. An over-worked employee cannot do a goodjob of taking care of animals. Goodstockmanship requires adequatestaffing levels. More efforts are also

needed to address problems of faultystunning equipment, ever-increasingline speed, and enforcement of theHumane Slaughter Act when viola-tions occur.

Attitudes can be changed, and thatchange can improve both animal wel-fare and productivity.

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