Poultry Slaughter Plant and Farm Audit: Critical Control Points for Bird Welfare (Updated July 2009)

Temple Grandin, Ph.D.

Core Criteria for Chicken Welfare Audit

The core criteria are so important that the ENTIRE audit is failed if any one of these items fails. They should be added to the National Chicken Council audit to strengthen the standard. The NCC audit is a useful tool for internal monitoring of welfare but the Core Criteria should be added.

Hatchery - Core Criteria

  1. Euthanasia of cull chicks - Two acceptable methods

  2. Mechanical chick handling devices: The following faults are an automatic failure

Chicken Growout Farm - Core Criteria

  1. Wet litter where soil transfers onto the birds in 5% or more of the building
  2. Ammonia level over 25 ppm minimum score; Excellent score is 10 ppm
  3. No life support backup in mechanically ventilated buildings. Acceptable methods are: The facility must have at least one of these methods. Not required for open side, naturally ventilated buildings.
  4. Overstocking - Measure market ready birds just before catching. The building is over stocked if birds are not able to move a minimum of 1 meter away as a person walks through them. Pile ups are not acceptable. The birds must have enough room to move away easily without getting on top of each other.
  5. Gait score - An acceptable standard is 95% of the birds can walk evenly for 10 steps.

Slaughter Plant - Core Criteria

  1. Poor cage maintenance - Must have 95% of the chicken compartments in good repair. No loose wire ends or broken plastic parts. A bent wire passes. In dump module or drawer systems, each deck or drawer is one compartment.
  2. Overstocked cages - Birds have enough room to all lie down at the same time without being on top of each other.
  3. Poor stunning - 99% of the birds must be rendered insensible by the stunner. Applies to both electric and controlled atmosphere.
  4. Poor bleed machine cutting - 99% must be effectively cut by the bleed machine.
  5. Live birds in the scaulder - There must be no uncut red birds. All birds that miss the bleed machine must be cut by the backup bleeder person.
  6. Excessive broken wings - More than 3% on a per bird basis fails (all bird weights). Includes both broken and dislocated wings. See slaughter audit for more details on best practice percentage. 1% is excellent for light weight birds.

Acts of Abuse or Neglect

  1. Throwing birds.
  2. Stomping on birds.
  3. Broken or mis-adjusted catching equipment on the farm or broken plant equipment that causes visible bird injuries, or crushes them.
  4. Putting live birds in the trash.

Additional faults that are an automatic failure

  1. Raising birds in near darkness. The eyes and combs of the birds must be visible.
  2. Poorly maintained or malfunctioning feeding or watering equipment. The farm fails if more than 5% of the waterers or feeders are not working.

Numerical Scores for Slaughter Plant Audit: Score 300 or more birds for each variable

  1. Stunner Efficacy Percentage: Score 300 or more preferably from different groups. 100% Excellent, 99% Acceptable.

  2. Bleed Machine Efficacy Percentage: 100% Excellent, 99% Acceptable.

  3. Are all red birds cut? Yes/No. If uncut red birds are found, this is an indicator that live birds are going into the scaulder. Limits must be set: I suggest 1 per day would be allowed. Some plants and auditors conduct their part of the audit by monitoring birds as they enter the scaulder. All birds must be cut and show no signs of sensibility.

  4. Percent broken wings: 1% maximum passing score, under 0.5% excellent (per bird basis) for birds weighing less than 6.8 lbs (3kg). Count broken wings with feathers on to avoid counting damage from feather removal equipment. This includes dislocated joints. For large birds weighing 6.8 lbs (3kg) to 9 lbs (4kg), the maximum passing score is 3%. The very best operations processing heavy chickens have broken wing percentages of 2.5 to 3%. Any plant that has more than 3% broken wings fails the audit regardless of bird size.

    Percentage of chickens with broken or dislocated wings in 22 United States and Canadian processing plants
    Percentage of birds with broken wings Number of plants Percentage of plants
    1% or less 8 36%
    2% to 1.01% 6 27%
    3% to 2.01% 6 27%
    Over 3% 2 9%

    Average bird weight 6lbs (2.75 kg). Birds were handled in the dump module system. All data collected in 2008.

    Average = 1.67%
    Best Plant = 0.20%
    Worst Plant = 3.80%

  5. Percent bruised thighs and drumsticks: 1% maximum passing score, under 0.5% excellent. Most likely hanger damage.

  6. Percent broken legs: None during an audit; 1/500 fails.

  7. Percent one legged shackling: None during an audit; 1/500 fails.

If damage to the birds is above the critical limits the plant should start a financial incentive plan for hangers and catching on the farm. People will handle chickens more carefully if they get a monetary reward.

The percentage of DOAs (Dead on Arrival) is a good measure of catcher performance. Acceptable 0.5%; excellent 0.25%.

Walk through Audit and answer Yes/No and do a short write up

  1. Is there enough room in the transport crates for all birds to lie down? Yes/No

  2. Are the birds clean? This is a measure of soil on birds from dirty litter on the farm. Yes/No (Check in crates and on the line)

  3. Did you see any birds get past the back up bleeder person? Yes/No

  4. Is there enough space so that the backup bleeder can easily observe? Yes/No

  5. Did you observe employee misbehavior? Examples: throwing birds or stepping on them. Yes/No

  6. Did you see birds injured by crate handling equipment? Yes/No

  7. Are the transport crates in good repair? Estimate percentage of broken crates or compartments in modular systems. Yes/No

  8. Are fans provided for cooling birds in transport crates in the lairage? Yes/No

  9. Are loose birch on the floor promptly picked up? Yes/No

On Farm Critical Control Points that can be measured at the Slaughter Plant

  1. Percent of birds with foot pad lesions.

  2. Percent of dirty birds that have been soiled by dirty litter.

  3. Percent of birds with hock burn.

  4. Percent with breast blisters.

  5. Percent with abnormal legs that are bent on rotated.

Average Percentage of Chickens free of defects that cause poor welfare

Normal gait score 72.6% The best flocks, regardless of weight,
will have 95% of the birds able to walk
10 steps with an even gait
0% hock burn 80.6%
Normal feet (paws) with no lesions 81.2%
Straight legs with no rotation or angle deviation 76.7%

The chickens in this study were housed in buildings with an average ammonia level of 10.4 ppm and a range from 1.3 ppm to 29.8 ppm. The average litter moisture was 18.3%. Seventy five percent of the flocks tested were Ross 308. Breed had no effect on any of the variables. A poor enviornment in the house increased the percentage of defects. Go to Animal Welfare Audits for gait scoring methods.

Further information on assessing chicken welfare on the farm is in:

Marion Stamp Dawkins, Christi A. Donnelly, and Tracey A. Jones, 2004. Chicken welfare is influenced more by housing conditions than by stocking density. Nature. Vol. 427, pp.342-344.

This large field study with nine poultry companies in commercial buildings used scoring methods that can be easily implemented on the farm. It can also be used as a starting point for setting critical limits on the above critical control points. The quality of the management of the house had a significant effect on poultry welfare.

Data collected by Temple Grandin on the very best farm growing heavy Ross and Cobb chickens weighing 6.8 lbs (3kg) to 9 lbs (4kg) had 95% normal gait score. A 52 day growing period was used to slow down growth.

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