Summary

Auditing of plants by major customers can greatly improve welfare. Animal welfare audits are being used by McDonald’s Corporation and their suppliers in the U.S. In 1996, prior to the McDonald’s audits only, three out of ten (30%) of the federal beef plants in the U.S. passed a stunning audit (Grandin 1997a, 1998). Audits by the McDonald’s HACCP team have raised the percentage to 14 out of 19 plants (74%) in the first half of 1999. Three out of five (60%) of federal beef plants in Canada passed the stunning audit in 1999. One large beef plant and one small beef plant failed the stunning audit and three large beef plants passed. During the plant visits both very good things and very bad things were observed. In one large cattle plant, cattle were moved quietly at a walk and a small provincial pork plant had excellent handling and stunning of pigs. They used no electric prods and had a perfect 100% stunning score. Another highlight of the plant visits was the kosher poultry plant. This plant is probably more humane than a regular chicken plant. Chickens are hung on the line after each bird is carefully held for the rabbi. One of the large poultry plants did an excellent job of improving poultry stunning and set an industry record of 99.8% stunned correctly. There was also a small federally inspected pork plant that had extremely good management who were interested in continuous improvement. They had perfect stunning techniques and have achieved extremely low levels of 4% PSE and 3% blood splash. They have achieved this with an old fashioned electric stunner and conventional drilling. To determine the blood splash percentage, all meat was completely boned.

The two worst plants in the survey were both federal, and they failed on both stunning and handling. Failing stunning scores were largely caused by scared , agitated cattle and pigs. The treatment of animals in these two plants would probably constitute abuse and cruelty. Another problem area is the disgusting condition of spent broiler breeder hens. Changes in rooster genetics have caused roosters to become overly aggressive which results in 50% of the hens loosing all the feathers on their rear ends. Roosters may also kill the hens. Aggressive roosters is a genetic problem which breeders throughout North America must correct. It is difficult to directly compare the 1999 survey with the Canadian 1995 survey because numerical scoring was not used in 1995. Many new, smaller plants, and some large plants, were visited in 1999, but in 1995 the survey concentrated on smaller plants. In the one province where a provincial plant was visited in 1995 and failed, the two provincial plants visited in this same province in 1999 passed. In 1999, 60% (9 out of 15) of the federal plants for all species passed the audit. In 1995, 19 federal plants were observed while operating for all species, and 14 plants (74%) passed the audit on stunning and slaughtering procedures. In 1999 the percentage dropped to 60%. Compared to 1995, poultry was an area of improvement. In 1995 two out of four poultry plants (50%) passed and in 1999 two out of three passed. Handling of pigs is a definite problem area. Handling of pigs was better in 1993 compared to 1999. In two large pork plants which had been surveyed in 1993, handling was worse in 1999. One plant which I described as having “the best handling I have ever observed in North America” in 1993 failed the handling audit in 1999.

These comparisons with earlier surveys indicate that measuring stunning and handling on a regular basis using a HACCP type approach is needed to improve and maintain standards. People manage the things that they measure.

Methods

Fifteen Federally Inspected Plants and Four Provincial Plants Were Inspected and Surveyed

Vocalization scoring is explained in Grandin (1997a, 1998ab) and Dunn (1990). The percentage of animals that slipped and fell and were prodded with an electric prod was estimated. Data on prodding could not be fully tabulated in some small plants due to very small numbers, but all plants were stun scored. Plant numbers on all tables are scrambled so that a single plant cannot be traced through the data. This was done to insure confidentiality. The minimum acceptable scores for passing the audit are:

• Cattle Stunning - 95% rendered insensible with one shot
• Pig and Sheep Electric Stunning - 99% correct wand placement
• Insensibility - zero tolerance, for sensible animals on bleed rail (automatic failure)
• Vocalization - 3% or less of cattle vocalize in stun box, restrainer and lead up chute, Hogs - reduce squealing - difficult to score
• Slipping and Falling - Fail if more than 1% fall or 15% slip
• Electric Prod Use - must be 25% of the animals or less to pass

Results and Discussion

All the plants had a stunner operator who was conscientious and was skillful. Two of the very small plants which slaughtered less than 50 cattle or calves per day failed due to damp cartridges. In larger plants cartridges were used up before they could get damp. I strongly recommend that cartridges in small plants should be kept in the office and no more than half a days supply should be on the kill floor. However, in large plants previous data showed that gun maintenance was the number one cause of poor stunning (Grandin 1997b, 1998a). Bull stunning was discussed in one of the small plants. A Koch Magnum captive bolt should be used for stunning bulls. To maintain maximum hitting power a separate bull gun should be kept that is cleaned and cared for like a fine hunting rifle. The horse plant did an excellent job with a rifle. Plant 5 used a pneumatic stun gun. The operator was skillful and the missed first shots were due to a sticking trigger mechanism. This problem can be easily solved by washing the trigger after every 100 head. Plant 7 failed due to cattle becoming agitated in the stunning box. Slipping in the stunning box and excessive electric prod use was the major cause of poor stunning in this plant.

Plant 5 had problems with automatic stunning due to excessive electric prodding of pigs which caused the animals to jam in the restrainer. The handling in this plant was the worst in the survey. Two pigs went though the stunner without being stunned and the automatic tongs caused squealing in three animals. A second audit of 100 pigs was done after the handling was improved. The machine performed at the acceptable level with no live pigs escaping and 99% correct placement.

One of the plants using C02 did not have the recommended gas concentration. Danish researchers recommend 90% or greater. Concentration was a concern because one pig kicked. This is a sign of anesthesia starting to wear off. It showed no other sensibility signs. C02 stunned pigs should be completely limp and floppy. Kicking and limb movements are permissible in captive bolt and electrically stunned animals. In electrically stunned animals, limb movements indicate that a seizure has occurred. A grand mal seizure is required to induce insensibility.

There have been concerns about the aversiveness of C02 stunning (Raj and Gregory, 1995). The literature is reviewed in the 1993 survey, and Grandin (1994). Observations indicate that it may be distressful for certain types of pig genetics such as pigs with the stress gene or Hampshire genetics. In humans there are genetic factors which determine whether or not a person will have a panic attack when they inhale C02 (Griez, 1990, Bellodi et al, 1998). There is a need for inspection windows so that the pig’s reaction to C02 can be observed. Some types of pigs react well to C02 and others react badly.

Assessing Insensibility

In pigs stunned with C02 the animal should be completely limp and floppy with no kicking or body movements. If an animal stunned with C02 kicks, this indicates that it must be watched very carefully for other signs of sensibility such as righting reflex or blinking. A pig stunned with C02 that kicks and shows no other signs of sensibility would be rated acceptable or borderline.

Regardless of the method of stunning used, any animal that has a righting reflex (lift up their head) on the bleed rail, vocalizes, blinks or has eye reflexes should be considered as improperly stunned. These criteria are conservative to help insure that animals will not return to full sensibility during slaughter.

Positive Effects of Customer Audits

The major incentive for the huge improvement between the 1996 USDA survey and the audits done in 1999 by the McDonald’s HACCP audit team is that plant management responded very positively when a major customer insisted on improvements. The McDonald’s Corporation and its ground beef supplies are now including animal welfare as part of their food safety evaluation of slaughter plants. At the time I conducted the 1999 survey in Canada, McDonald’s had not started its audits of Canadian plants. In the 1999 Canadian audit there were four federal beef plants that were large enough to be eligible to supply McDonald’s. Three of these plants (75%) passed the stunning audits and stunned 95% or more of the cattle correctly and one plant failed. The plant that failed, failed on stunning, insensibility and vocalization score. It failed on three different measurements. The other three passed all the welfare measurements.

A minimum acceptable standard for poultry stunning is to have 99% of the birds enter the water both in the correct position. This rating was attained by a McDonald’s supplier in England. In many North American plants, higher percentages of birds miss the stunner. Plant 1 failed due to the percentage of birds that regained a righting reflex prior to the bleeding machine. This was due to insufficient amperage. To reduce the incidence of birds that pull themselves up prior to the water bath, a shield should be installed so that they remain in the dark prior to the stunner. Plant number 1 also needed to improve shackling. There was about 1% shackled by one leg. When the supervisor was told about this, the incidence of one-legged shackled birds dropped to zero.

All plants rendered all birds completely insensible before they reached the scaulder. Three plants passed the audit and one failed. One company had made extensive modifications of their stunner to increase the percentage of chickens and small turkeys that were correctly stunned.

Below is a list of modifications which improved chicken stunning.

1. Use a longer, wider turkey stunner for chickens.
2. Warm water to reduce chickens pulling up out of the water bath.
3. Greater than 200 ma at 14 volts
4. Butt rail prevents birds from pulling up out of the water bath.
5. Really good shackle electrical grounding
6. Aeration of the water
7. Use granular salt for more accurate brine concentration.
8. Stunner set deep - Birds immersed to shoulders
9. Conveyor belting breast rub
10. Dark room
11. No bumps or jerks in the rail which excite the birds

Stunning Parameters Must Be Followed

Vocalization is a sensitive indicator of cattle distress. See American Meat Institute Guidelines and Grandin (1998 ab). It is measured on a yes/no basis in the stunning box, restrainer and lead-up chute. It is not measured in the yards. Each animal is scored as either a vocalizer or a non-vocalizer. In pigs, individual pig squeals are difficult to count, but squealing could be measured with a sound meter. Vocalization during handling, stunning or painful surgical procedures is a sign of stress in cattle and pigs (Dunn 1990, Warriss et al 1994, White et al 1995). To receive an acceptable rating a plant must have 3% or less of the cattle vocalize during handling and stunning. In small plants vocalization in cattle can be reduced by reducing the time cattle or calves stand in a chute or stunning box. A bovine should not be placed in the stunning box until it is ready to be stunned. This is especially important in very small plants such as plants 3 and 4, which slaughtered under 50 cattle per day. In small plants the intervals between animals is longer. One saler heifer left alone in the lead-up chute continually tried to escape and jump out. In small plants when very wild cattle are handled, it is recommended to stun the last two animals in rapid succession to avoid stressing a lone animal left alone in the chute. Only one animal should be placed in a stunning box. The only exception to this rule is when extremely wild animals are handled. Two animals must never be deliberately put in a stun box, but if two wild cattle or bison run in, it would probably be less stressful to not attempt to back one out.

I would rate the kosher poultry plant as having better animal welfare than the poultry plants using electric stunning. Each bird was carefully held for the rabbi and then placed on the shackle after the cut. In a conventional poultry plant birds are hung on the shackles prior to stunning. One improvement that could be made at the poultry plant would be to install a plastic guide strip made from a meat cutting board to stop the metal clattering sound of the cones. This clattering is louder than a regular poultry plant.

Conditions at the kosher calf plant were not acceptable due to the fact that the calves slipped on the smooth floor of the restraint box. Slipping caused the calves to become agitated which delayed the onset of unconsciousness. A calm animal will lose consciousness more quickly (Grandin 1994). Fixing the floor by welding steel rods to it to prevent slipping will keep the calves calmer. I recommend that the calf should be held in the restraint box with the head holder released for 5 seconds after the cut. If it does not collapse within this time it should be stunned with a captive bolt. Two captive bolt guns are recommended in the bleed area so that calves that do not collapse quickly can be stunned. The speed of the rabbi’s cut will also affect the onset of unconsciousness. A rapid throat cut is more effective than a slow cut (Grandin, 1994). This may be due to differences in blood vessels sealing off. A slow cut may cause more stretching which may promote sealing off

Due to small numbers of animals in some small plants it was not possible to fully observe and objectively score slipping and falling in all plants. Plants seem to fall into two categories. . .of few problems with slipping and falling and large problems. The number one problem area is the beef or calf stunning box. Grandin (1997b, 1998a) found that roughly half of the beef plants that had stunning boxes had problems with slipping that caused the animal to become agitated. The easiest method for preventing slipping in a stunning box is to install a metal grating on the floor. The metal grating should be constructed from 2 cm diameter metal bars in an 20 cm to 25 cm square pattern. The bars must be welded flush on the floor. Slipping in the stunning or restraint box was a serious problem in two plants. Plant 14 had a serious slipping and falling problem in their beef stunning box which must be corrected. In plant 6, calves slipped on the floor of the kosher restraint box, which caused the calves to become agitated.

When evaluating handling, vocalization score should be given more weight than prod use score. Squealing, moos and bellows are a sensitive indicator of animal distress. There were two pork plants (2 out of 6) that failed on prod use. Some of the problems were due to distractions which are discussed in the distractions section. In both of these plants too many pigs were put in the crowd pen. In one plant, handlers used prods with 110 volts which made every pig squeal. They were the worst prods in North America. American Meat Institute guidelines specify that prods that make most animals vocalize when briefly applied cannot be used. This plant must reduce the voltage in their prods and stop abusive handling of pigs. The abuse of pigs in plant 10 with electric prods constitutes cruelty to animals.

Prodding pigs and making them get excited damages meat quality. Tests conducted in the U.S. showed that quiet handling in the stunning chute can reduce PSE 10%. Agitation and excitement during the last five minutes in the stunning chute can lower pork quality. One pork plant had excellent handling and low PSE of only 4% and the plant with excessive prod use had 14% PSE. All three plants that failed on prod use had distractions which caused balking.

Two cattle plants that had a stunning box and no distractions that would make animals balk had stun boxes which were in the barn. The stunned animal was rolled through a door in the barn wall. This is an excellent design. Grandin (1996, 1997a, 1998c) contains information on lighting problems and other distractions that will impede animal movement, such as an air draft blowing into the face of approaching animals or lighting problems. Increased illumination at a chute entrance will often reduce balking. (Also see www.grandin.com.) In two plants handling of pigs improved and balking was reduced when a light was added at the entrance of the stunning chute in one plant, and a broken window blind slat that admitted blinding light was blocked in the other plant. Animals will move towards the light but they will not approach blinding light. Chute entrances and stun box entrances should be brightly illuminated with indirect lighting. In the plant with the broken window slat a fan was shut off to stop air from blowing in the faces of approaching pigs. Plant 10 also had a problem with a fan blowing air into the faces of approaching pigs. It also had back stop gates in the chute entrances which caused pigs to balk. Backstop gates that prevent backing up often create more problems than they solve. Finding distractions that make animals balk will reduce the need for backstop gates. In most facilities backstops left closed near the chute entrance increased balking. To find the things that make animals balk, one has to get down in the chutes and take a pig or cow’s eye view.

Plant 11 had extremely good handling of cattle in the yards. Cattle were moved very quietly with a stick with a piece of plastic on the end. The only place an electric prod was needed was at the restrainer entrance. The vocalization score in this plant was only 2%. This shows that this plant had calm cattle. One factor which made handling excellent in Plant 11 was removal of all distractions that cause balking.

Plant 14 had distractions which made quiet movement of cattle into the stunning box impossible. Shutting the door leading onto the stunner’s platform reduced noise in the lead up chute and prod use was reduced from 99% to abut 75% of the animals. Cattle still balked at seeing people, air drafts and seeing carcasses moving. Installation of shields to block the incoming animal’s vision should reduce balking.

Non-Ambulatory Downer Handling

Animal Handling Transport Observations

Poultry

One poultry company had switched from Bright Coops, where chickens are loaded into a compartment through side doors to the Auto Flow System, where the birds are loaded into drawers which open like a dresser. The Autoflow System had a great reduction in dead birds. The Bright Coop System, which is popular in the U.S., had about 1% DOAs and the Auto Flow System had only 0.5%. Details of design are important. One poultry company in the U.S. tried the Auto Flow System and took it out because damage increased. This was due to mistakes in design. There must be a gap between the edge of the drawer and the pallet rack to prevent the bird’s head or wing from being caught when the drawer is closed. The Auto Flow System in the U.S. lacked this gap and caused more damage then Bright Coops. A 2.5 cm gap is the difference between system failure and success. This new system I observed in Canada also had very heavy molded plastic drawers which did not break easily. Earlier drawer designs used in the U.S. were prone to breakage. The Canadian drawers looked like they had been made by a milk crate company and they were engineered for strength. They had rounded solid molded corners and bracing molded into the floor and walls.

Cattle & Pigs

There was one pork plant and one beef plant that had extreme over use of electric prods. Animals balked due to distractions such as air drafts blowing in their faces, noise and seeing movement up ahead. In the pork plant, employees were poorly trained and constantly prodded the pigs.

Cull Broiler Breeder Chickens in Disgusting Condition

Continuous Measurement with Objective Scoring

People manage things that they measure and they let lapse things that they don’t measure. It is just like microbiological counts. Microbiological counts would increase and get worse unless they are constantly monitored and measured. Handling and stunning require the same approach. The Quality Control Department in each plant should audit handling and stunning on a continuous basis, and use objective scoring . Objective scoring should also be used by government officials to maintain an acceptable level of welfare.

Conclusions

References

Blackmore, D.K. and Newhook J.C. 1981. Insensibility during slaughter of pigs in comparison to other domestic stock. New Zealand Veterinary Journal 29: 219-222.

Council of Europe 1991. Council Directive of 18 November on Stunning of Animals Before Slaughter (74/577/EEC). Official Journal of the European Communities, No. L 316, 26 November, 10-11.

Dunn, C.S. 1990. Stress reaction of cattle undergoing ritual slaughter using two methods of restraint. Veterinary Record 126:522-525.

Grandin, T. 1993. Report on Handling and Stunning Practices in Canadian Meat Packing Plants, conducted for Agriculture Canada, The Canadian Federation of Humane Societies and The Canadian Meat Council.

Grandin, T. 1994. Euthanasia and slaughter of livestock, Journal of the American Veterinary Medical Assoc. 204: 1354-1360.

Grandin, T. 1995. Report on Handling and Stunning Practices in Canadian Meat Packing Plants, conducted for Federal Food of Animal Origin Division, Canadian Meat Council, Canadian Federation of Humane Societies and Canadian Poultry and Egg Producer’s Council.

Grandin, T. 1996. Factors that impede animal movement at slaughter houses. J. Amer. Vet. Med. Association. 209: 757-759.

Grandin, T. 1997a. Good Management Practices for animal handling at stunning. American Meat Institute, Washington, D.C.

Grandin, T. 1997b. Survey of Handling and Stunning in federally Inspected Beef, Pork, Veal and Sheep Slaughter Plants. ARS Research Project No. 3602-32000-002-08G, USDA.

Grandin, T. 1998a. Objective scoring of animal handling and stunning practices at slaughter plants. J. Amer. Vet. Med. Association. 212: 36-39.

Grandin, T. 1998b. The feasibility of vocalization scoring as an indicator of poor welfare at slaughter. Appl. Animal Behavior Sci. 56: 121-128.

Grandin, T. 1998c. Solving livestock handling problems in slaughter plants In: N.G. Gregory, Animal Welfare and Meat Science, CAB Publishing, Wallingford, Oxon, United Kingdom.

Griez, E., J. Zandbergen, and H. Pols. 1990. Response to 35% CO2 as a marker of panic and sever anxiety. Am. J. Psychiatry 147:796-797.

Hoenderken, R. 1983. Electrical and carbon dioxide stunning of pigs for slaughter. In: Eikelenbook G. ed. Stunning of Animals for Slaughter. Boston: Martinus Nijhoff Publishers, 59-63.

Raj., A.M. and N.G. Gregory. 1995. Welfare implications of gas stunning of pigs. 2. Stress of induction of anesthesia. Animal Welfare 5:71-78. Warriss, P.D.; Brown, S.N. and Adams, S.J.M. 1994. Relationships between subjective and objective assessments of stress at slaughter and meat quality in pigs. Meat Science, 38: 329-340.

White, R.G.; DeShazer, J.A. and Tressler, C.J. et al 1995. Vocalizations and physiological response of pigs during castration with and without anesthetic. J. Animal Science, 73: 381-386.

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