Adjustment of Poultry Welfare Standards for Broken Wings on Heavy Chickens during Handling, Transport, and Slaughter: An Acceptable Score is 2% or Less

by Temple Grandin
Updated July 2010


Poultry processing plants that are being audited by a strict restaurant auditing program are doing such a good job on reducing broken wings that the maximum percentage of chickens with broken wings should be made more strict. For birds weighing more than 5.5 lbs (2.5 kg) to pass an animal welfare audit, broken wings should be 2% or less on a per bird basis. This recommendation is based on data collected at 17 U.S. chicken plants that were audited twice. All these plants processed chickens that weighed over 5.5 lbs (2.5 kg). The average for the 34 audits was 1.43% of the birds had a broken wing. Seventy percent of the plants passed BOTH audits with 2% or less broken wings. One plant with huge 7.5 lb (3.4 kg) birds had only 0.60% broken wings. Table 1 shows the range of the data based on the worst of the two scores for each plant. Seventy percent of the plants had 2% or less broken wings. Therefore the standard for an acceptable score on broken wings should be changed from 3% to 2% of birds. This applies to all birds that weigh 5.5 lbs (2.5 kg) and over. To receive an excellent score, broken wings should be 1% or less.

Table 1: Percentage of Heavy Chickens with Broken Wings in 17 U.S. Plants
Number of Plants Percentage of Plants
Excellent: Less than 0.5% 1 5%
Excellent: 1% or less 3 18%
Excellent: 1.5% or less 5 29%
Acceptable: 2% or less 3 18%
Not Acceptable: 2.5% or less 0 0%
Not Acceptable: 3% or less 2 12%
Serious Problem: Over 3% 3 18%


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