2000
McDonald’s Audits of Stunning
and
Handling in Federally Inspected Beef and Pork Plants
Temple Grandin
Department of
Animal Sciences
Colorado State
University
Fort Collins CO 80523
Stunning of beef cattle has continued to improve compared to the USDA survey done in 1996 and last year’s 1999 McDonald’s audits. Stunning was scored in 49 Federally inspected beef plants in 12 different states. The plants were evaluated with the scoring system in the American Meat Institute guidelines, by the McDonald’s HACCP team. Forty-one percent of the plants stunned 99% to 100% of the cattle correctly with one shot and 90% performed at the 95% level or better on first shot stunning efficacy (Table 1). The average first shot stunning efficacy percentage for all plants was 97.87%. Four plants (8%) had not acceptable first shot efficacy percentages of 94% and one plant (2%) failed with a score of 87%. In 1999, four plants (10%) had either not acceptable or failing scores. In the second half of 2000, unannounced audits were started. A comparison of cattle stunning scores indicated that significantly more plants in the announced group had excellent scores of 100% to 99% first shot efficacy (P = > .05) (Table 2). However, the difference between announced and unannounced audits was much smaller than the huge improvement in stunning which occurred when the McDonald’s audits started in 1999. A USDA survey in 1996 indicated that only 30% of the plants were able to stun 95% or more of the cattle with one shot.
Cattle vocalization (moos and
bellows)
Compared to 1999 vocalization scores have improved (Table 3). In 2000, 80% of the plants passed the vocalization audit with 3% or less of the cattle vocalizing. In 1999, 71% of the plants passed. In 2000 51% of the plants had excellent scores 0% to 1% of the cattle vocalizing. None of the plants in 2000 received a serious problem rating of over 10% of the cattle vocalizing. In 1999, two plants (5%) had serious problems when over 10% of the cattle vocalized during stunning and handling. In 2000 balking at the stun box entrance and refusing to move was the primary cause of vocalization. When cattle balk an electric prod is usually required to move them. Table 4 shows causes of vocalization. Table 5 shows that vocalization was higher in plants where a high percentage of cattle balked and backed up.
Best Practices – A number of best practices are recommended for handling and stunning beef cattle (Chart 1).
Cattle Insensibility – All but one of the audited plants passed on insensibility on the bleed rail. However, there was a TV news report which showed serious problems with cattle abuse in a large plant. The report aired in two large cities. This video would have failed an audit for insensibility and electric prod use.
Problem Areas – Overall, the beef plants continue to improve but one problem area was cattle balking and refusing to enter stunning boxes or slipping in a stunning box. This can cause stunning and handling problems. The stunning boxes can be fixed by redesigning noisy gates and possibly slowing down line speeds.
Another problem area is the formation of a two tier market. Plants which are audited on a regular basis by a large customer such as McDonalds will have higher welfare standards than plants which are not audited by a major customer. For example, plants that actively buy debilitated, skinny, non-ambulatory cattle will form a low end market which may be outside of an auditing system.
Plants that process mature cows and bulls need to be careful with Herefords that have thick mats of curly hair on the forehead. Thick hair may reduce bolt velocity which is required for an effective stun. One Hereford cow had a possible sign of partial sensibility when it was shot correctly.
Summary for Pork Plants
Nineteen Federally inspected pork slaughter plants were audited in eight different states. Eighty-nine percent (17) of the plants placed the stunning wand correctly on 99 to 100% of the pigs (Table 7). Sixty-eight percent of the plants (13) energized the stunning wand correctly so that 100% to 99% of the pigs remained quiet when the stunning wand was applied (Table 8). Two plants (10%) failed the stunning audit when scores for placement and “hot handing” were combined. A “hot wand” is scored if the pig squeals when the stunner is applied. See 1999 report for scoring method (www.grandin.com), click on surveys.
Insensibility on the bleed rail – Eighty-four percent of the plants (16) rendered all pigs completely insensible on the bleed rail. In three plants, one or more pigs had eye reflexes but all other signs of return to sensibility were absent (Table 9). All pigs were completely insensible prior to scalding. Eight plants (42%) that had perfect stunning scores for both placement and absence of “hot wanding” had 100% insensible pigs. The two plants that failed on stunner placement and “hot wanding” had pigs with eye reflexes. These plants have been re-audited and the problems have been corrected. See charts 2 and 3 for trouble shooting electrical stunning and determining insensibility.
Squeal Scoring – Improvements in pig handling have greatly reduced squealing during handling of pigs. Forty-four percent of the plants out of 18 scores had excellent scores (Table 10). One plant received a not acceptable rating. These improvements are due to two major factors, handling improvements and changes in pig genetics. Many producers have stopped breeding ultra lean nervous, excitable pigs which are difficult to handle.
Electric Prod Use on Pigs – Sixty-eight percent of the plants had eliminated the use of electric prods in the crowd pen which leads up to the single file chute (Table 11). Four plants (21%) had completely eliminated electric prods in the entire system. These four plants have line speeds of 860 or less pigs per hour per restrainer system. Only one plant received a not acceptable rating for electric prod use.
Best Practices – A number of best practices are recommended for stunning and handling pigs (chart 4).
Problem Area – Determining insensibility in electrically stunned pigs is more difficult than determining insensibility in cattle stunned with captive bolt. In cattle, any eye movement after stunning is a sign of a poor stun. In electrically stunned pigs some animals will have nystagmus (eye vibrating). This is permissible as long as all other signs of return to sensibility are absent. Nystagmus must not be confused with a natural blink where the eye closes and then reopens. Another problem is that poking the eyes of electrically stunned pigs with one’s finger may cause movements such as an eye that is stuck shut popping open. This is not a corneal reflex and it may fool an auditor into thinking that he/she found a pig that is starting to return to sensibility. To avoid these problems, it is best to observe without touching the eyes. If a pig does a natural blink like a live pig in the yards, the plant should be failed.
Conclusions – Stunning of beef cattle has continued to improve and handling of both cattle and pigs continue to get better and better. Many plants have greatly reduced electric prod use. The main problem areas that need to be fixed in a few plants are overloaded equipment and pig stunning procedures.
Table 1. Captive bolt stunning in 49 beef plants in the U.S. during 2000.
|
Percentage of
cattle stunned with one shot |
Number of plants |
Percentage of plants |
Line speed range |
|
Excellent 99 to 100% |
20 |
41% |
11 to 390/hr |
|
Acceptable 98 to 95% |
24 |
49% |
90 to 390/hr |
|
Not Acceptable 94 to 90% |
4 |
8% |
30-210/hr |
|
Serious Problem Less than 90% |
1 |
2% |
200/hr |
Reason for poor stunning in 5 plants:
1. Stunner maintenance
2. Stunner ergonomics
3. Wet cartridges
4. Thick curly hair old Hereford cow
Table 2. Comparison of announced versus
unannounced audits on captive bolt stunning of cattle in 49 beef plants. This
table only contains a plant’s initial 2000 audit.
|
|
Average % of cattle stunned with one shot |
Percentage of plants excellent 99 to 100% |
Percentage below 95% |
|
Announced Audit |
98.8% |
58% (14)* |
0% (0) |
|
Unannounced Audit |
96.9% |
25% (6) |
21% (5) |
|
|
|
Poor stunner maintenance or ergonomics were the reason for poor stunning |
|
There were significantly more plants in the un-announced audit group that had excellent stunning scores X2 = 5.48 > .05
N = 24 Announced plants and 27unannounced plants.
There were 24 plants which had announced audits and 27 plants that had unannounced audits. There were three plants where the unannounced audit was a re-audit. The first plant had a random unannounced re-audit and its stunning score was 99% for both audits. The second plant was re-audited because it failed the handling audit. Its first stunning scores was 96% and its unannounced stunning score was 97%. The third plant was re-audited because there was a sensible animal on the rail. Both audits were unannounced and the stunning scores were 97% and 98%.
Table 3. Percentage
of cattle vocalizing in 49 beef plants in the U.S. during 2000.
|
|
Number of plants |
Percentage of plants |
Plant line speed range |
|
Excellent 0 to 1% |
25 |
51% |
11 to 390/hr |
|
Acceptable 2 to 3% |
14 |
29% |
35 to 350/hr |
|
Not Acceptable 4 to 10% |
10 |
20% |
40 to 300/hr |
|
Serious Problem Over 10% |
0 |
0% |
- |
Vocalization percentages improved compared to 1999. In 2000 79% of the plants had either excellent or acceptable vocalization percentages. In 1999, only 71% of the plants achieved this. In 1999, 2 plants (5%) had serious problem with over 10% of the cattle vocalizing.
Table 4. Cause of vocalization percentages of
over 3% in 10 out of 49 beef plants.
|
Plant No. |
Cause of Vocalization |
Percentage of Cattle Vocalizing |
|
Plant 1 |
38% of the cattle balked and refused to enter stun box. All of these cattle had to be electric prodded |
8% |
|
Plant 2 |
Constant balking and backing up caused by cattle seeing a loose piece of metal moving. Corrected by holding the loose metal still. |
8% |
|
Plant 3 |
Balking at noisy chains on the stun box gate. Two vocalizations due to electric prodding of balking animals and four due to jamming in the box. Electric prod only used on balking cattle. |
6% |
|
Plant 4 |
Balking at the stun box entrance and seeing out through the side of an open chute. Electric prod only used on balking cattle |
7% |
|
Plant 5 |
Balking at stun box entrance due to seeing flapping conveyor belting and shiny metal. Pinching from loose metal panel. |
7% |
|
Plant 6 |
Animal left in stun box too long. |
|
|
Plant 7 |
Balking at restrainer entrance and electric prod use on half the cattle. |
7% |
|
Plants 8, 9, 10 |
Not recorded |
4 to 7% |
Table 5. Vocalization is higher in beef plants
with excessive balking.
|
Low Balking Plants |
High Balking Plants |
||
|
Percent of cattle backing up in the chute |
Percent vocalizing |
Percent of cattle backing up in the chute |
Percent vocalizing |
|
0% |
1% |
38% |
8% |
|
3% |
2% |
25% est. |
8% |
|
Avg. 1.5% |
1.5% |
31.5% |
8% |
If a plant’s vocalization or electric prod score is not acceptable, balk score the plant to determine if the problem is caused by equipment or untrained or unsupervised people. High levels of balking and backing up are more likely to be an equipment problem.
Table 6. Electric prod use in 49 beef plants.
|
Percent of cattle electric prodded |
Electric Prod Use Crowd Pen |
Electric Prod Use Stun Box or Restrainer Entrance |
||
|
|
Percent of plants |
Number of plants |
Percentage of plants |
Number of plants |
|
0% Excellent |
57% |
28 |
16% |
8 |
|
5% or less Excellent |
16% |
8 |
39% |
19 |
|
6% to 25% Acceptable |
4% |
2 |
12% |
6 |
|
26% to 49% Not Acceptable |
2% |
1 |
2% |
1 |
|
50% or more Serious Problem |
2% |
1 |
12% |
6 |
|
Missing Data |
18% |
9 |
18% |
9 |
Percentage estimates were missing from five plants due to use of audit forms where the percentage of cattle electric prodded box was omitted. It is unlikely that missing data plants would have been in the serious problem or not acceptable category.
Table 7. Electric stunner wand placement on pigs
in 19 U.S. pork plants for passage of current through the brain.
|
Percentage of pigs with correct wand placement |
Percentage of plants |
Number of plants |
Line speed per restrainer |
|
100% Correct Excellent |
68% |
13 |
70 to 1060/hr |
|
99% Correct Acceptable |
21% |
4 |
750 to 1105/hr |
|
98% or less Not Acceptable |
11% |
2 |
900 to 1170/hr |
Reasons for poor wand placement
1. Poor stunner wand ergonomics
2. Line speed 1170 per hour at the restrainer.
Table 8. Electric stunner “hot wanding” where the
wand is energized before it fully contacts the pig. Scored yes if pig squeals
when the wand is applied.
|
Percentage of pigs hot wanded |
Percentage of plants |
Number of plants |
Line speed range at the restrainer |
|
0% Hot Wanding Excellent |
53% |
10 |
380 to 1060/hr |
|
1% Hot Wanding Acceptable |
16% |
3 |
800 to 1100/hr |
|
2% to 3% Not Acceptable |
21% |
4 |
850 to 1100/hr |
|
4% or more Serious Problem |
10% |
2 |
70 to 900/hr |
Reason for excessive hot wanding:
1. Poor stunner wand ergonomics
2. Defective switch on the stunning wand
3. Line speed over 1060/hr
Table 9. Plants with return to sensibility problems in
2000*.
|
|
Species |
Reason |
|
Plant 1 |
Cattle (fully sensible) |
Overloaded equipment and constant backing up and balking of cattle at stun box entrance. |
|
Plant 2 |
Cattle (partial sensibility) |
Slick floor in stunning box caused slipping which made stunning difficult. |
|
Plant 3 |
Pigs (eye reflexes only) |
Incorrect wand placement and excessive hot wanding due to poor stunner wand ergonomics. Blinking 60 seconds after stunning. |
|
Plant 4 |
Pigs (eye reflexes only) |
Fatigued operator wand placement. Blinking 60 seconds after stunning |
|
Plant 5 |
Pigs (eye reflexes only) |
Insufficient amperage for stunning sows blinked within 5 seconds after stunning. |
1. Eight pork plants (42%) with 100% correct placement and 0% hot wanding had 100% insensibility on the bleed rail. This shows that proper stunning procedures will produce 100% in sensible pigs.
*Note – One of the beef plants on this table was the plant that appeared on a TV news report. One hundred percent of the cattle were rendered insensible when the plant was re-audited.
Table
10. Pig handling in 18 pork plants –
Squeal scoring
|
Percent time quiet |
Number of plants |
Percent of plants |
Line speed range |
|
50% or more of the time quiet Excellent |
8 |
44% |
600 to 1000/hr |
|
49% to 16% of the time quiet Acceptable |
9 |
50% |
70 to 1080/hr |
|
15% or less of the time of the time quiet Not Acceptable |
1 |
5% |
1065/hr |
Squeal scoring is done by scoring each stunning cycle on a yes/no basis of quiet or heard a squeal anywhere in the stunning room. Hot wand squeals excluded.
Table 11. Electric prod use in
19 pork plants.
|
|
Electric Prod Use in Crowd Pen |
Electric Prod Use at the Restrainer Entrance |
|
||
|
% of pigs electric prodded |
% of plants |
Number of plants |
% of plants |
Number of Plants |
Line speed range |
|
0% Excellent |
68% |
13 |
21% |
4 |
380 to 850/hr |
|
1% to 15% Good |
5% |
1 |
42% |
8 |
870 to 1060/hr |
|
16% to 25% Acceptable |
0% |
0 |
16% |
3 |
900 to 1080/hr |
|
26% to 49% Not Acceptable |
5% |
1 |
5% |
1 |
900/hr |
|
50% or more Serious Problems |
0% |
0 |
0% |
0 |
- |
|
Missing Data |
|||||