Horse welfare at slaughter: A novel approach to analyse bruised carcasses based on severity, damage patterns and their association with pre-slaughter risk factors.

This study examines horse welfare before slaughter, using a new method to assess the severity and patterns of bruises on horse carcasses. The researchers find that bruising is a common issue, especially in animals transported for long periods, and indicates potential welfare issues related to transportation and handling.

Research Method and Data Collection

• The researchers adopted a novel veterinary forensic approach to examine bruising on horse carcasses, with a focus on the severity of the bruising and its position on specific anatomical areas.
• Data was collected from 113 horse journeys, where the animals were transported from the United States and Mexico to a slaughterhouse in Mexico.

Results and Findings

• The findings revealed a high prevalence of carcass bruising, with 79% of the analysed horse carcasses showing bruising.
• Bruising was particularly problematic in journeys that exceeded 12 hours. This observation applied irrespective of the horse’s country of origin, sex, age, the duration of time spent in a holding pen before slaughter (lairage time), or the type of vehicle used for transportation.

Analysis

• Researchers further conducted a multivariable logistic regression to understand the dispersion of the most severe bruises on the carcasses.
• The analysis showed that the most severe bruises were not randomly dispersed on the carcass but rather showed a certain pattern.
• In particular, such severe bruises were often associated with the presence of medium-sized bruises on the abdominal wall, front and rear limbs of the animal.

Damage Patterns

• Furthermore, researchers identified four damage patterns based on the location of the bruises: severely concentrated bruising, and mild bruising found on the rear limbs, thoracic wall, or dispersed throughout the carcass.

This study highlights the importance of improving the transportation conditions and handling of horses to ensure their welfare up to the point of slaughter, as indicated by the fact that long journey times were associated with a high prevalence of severe bruising.