Objective: To develop objective methods for monitoring animal welfare at slaughter plants to ensure compliance with the Humane Methods of Slaughter Act.
Design: Survey of existing procedures.
Sample population: 24 federally inspected slaughter plants.
Procedure: 6 variables evaluated at each plant were stunning efficacy, insensibility of animals hanging on the bleeding rail, vocalization, electric prod use, number of animals slipping, and number of animals falling.
Results: Of 11 beef plants, only 4 were able to render 95% of cattle insensible with a single shot from a captive-bolt stunner. Personnel at 7 of 11 plants placed the stunning wand correctly on 99% or more of pigs and sheep. At 4 beef plants, percentage of cattle prodded with an electric prod ranged from 5% at a plant at which handlers only prodded cattle that refused to move to 90% at another plant. Use of electric prods at 6 pork plants scored for prod use ranged from 15 to almost 100% of pigs. Percentage of cattle that vocalized during stunning and handling ranged from 1.1% at a plant at which electric prods were only used on cattle that refused to move to 32% at another plant at which electric prods were used on 90% of cattle and a restraint device was inappropriately used to apply excessive pressure.
Clinical implications: To obtain the most accurate assessment of animal welfare at slaughter plants, it is important to score all of the aforementioned variables.