Factors that impede animal movement at slaughter plants.

Factors that impede animal movement in slaughter plants and that are likely to cause excitement, stress, or bruises are major mistakes in the design of chutes and stockyard pens; lack of training or poor supervision of employees; distractions that impede animal movement, such as sparkling reflections on a wet floor, air hissing, high-pitched noise, or air drafts blowing down the chute toward approaching animals; poor maintenance of facilities, such as worn out or slick floors that cause animals to fall; and animals from genetic lines that have an excitable temperament. Veterinarians need to be aware of these factors because such factors can cause animals to balk and become excited, which may result in excessive prodding. When a handling system is being evaluated, one must be careful to discriminate between a major design mistake and small distractions that can be easily corrected, but that can ruin the performance of the best systems. A survey of 29 Canadian slaughter plants revealed that 21% (6 plants) had slick floors that would cause animals to slip and fall, and 27% (8 plants) had high-pitched motor noise or hissing air that caused animals to balk. Air drafts blowing down the chutes, which will often impede animal movement, were a problem in 10% (3) of the plants. Simple modifications of lighting and elimination of air drafts and hissing will often greatly improve animal movement.