Reducing noise associated with restraint box operation can facilitate animal handling in cattle abattoirs

To evaluate in a range of abattoirs in Australia, the effect of a fully nylon-lined, noise-reducing restraint box on animal handling practices during pre-slaughter handling with a view to improving animal welfare by facilitating the movement of animals through the race into restraint for stunning.

Data were collected from eight meat processors in Australia, with pre- and post-installation data available for four, and post-installation data available for all eight. Two separate analyses were conducted: one to compare pre- and post-installation data to evaluate the impact of the noise-reducing restraint box on animal handling practices, and another to investigate the variability between processors in the handling interventions required post-installation of the noise-reducing restraint box. Individual handling parameters (physical intervention/aid or noise, such as whistling or hitting the race to help animals move forward) were measured for each processor.

Overall, there was a noticeable reduction in almost all handling parameters, with a few exceptions. For both physical and noise interventions, there was a significant interaction between treatment and processors (p < 0.01). Cattle received less handling aid post-installation compared to pre-installation (marginal mean (MM) number of events = 1.64 (95% CI = 1.47-1.84) vs. 3.14 (95% CI = 2.90-3.41); p < 0.01). However, handling noise was increased post-installation compared to pre-installation (MM = 1.08 (95% CI = 0.94-1.22) vs. 0.70 (95% CI = 0.61-0.81); p < 0.01). Thus, the use of the noise-reducing restraint box led to a reduction in the use of physical handling methods, but there was an increase in the use of other less stressful forms of coercion such as staff vocalisations. Post-installation analysis showed that handling interventions (aid and noise) varied significantly among processors (p < 0.05).

The noise-reducing restraint box reduced the need for physical coercion, potentially improving animal movement through the race and offering improvements in production efficiency, animal welfare and staff morale. However, variation between processors indicates that there are other factors influencing system flow and animal welfare.