Associations between Pre-Slaughter and Post-Slaughter Indicators of Animal Welfare in Cull Cows

SIMPLE SUMMARY: Old, sick, and low-production cows are called cull cows, and they are sent from the farms to slaughter to produce meat. Cull cows may be more vulnerable than other categories of cattle regarding alterations of their welfare, but most studies linking animal welfare to meat quality have been carried out in steers and heifers of higher commercial value. In this study, we registered health of cull cows at arrival at a slaughterhouse and handling of the cows during the stunning process and associated those variables with carcass bruising and condemnations; the latter are a reflection of the treatment received by the animals before death and therefore can be used as indicators of animal welfare. We found a high percentage of cull cows arriving with low body condition (skinny), as well as presenting lameness and mastitis. During the stunning process 16% of cows did not fall unconscious after the first shot with the penetrating captive bolt gun. Skinny cows and those with mastitis were more likely to be condemned; skinny cows also presented more severe bruises. We conclude that for cull cows the main animal welfare issue originates at farm level, and cows should be culled sooner. ABSTRACT: The objective of this study was to evaluate the welfare of cull cows in a slaughtering plant, using indicators of health on arrival and indicators of handling during the stunning process. These pre-slaughter indicators were associated with post-slaughter indicators of the same cows, such as carcass bruising and condemnations. Transport staff surveys showed that all drivers had been trained on animal welfare. All loads of cows came directly from farms and had an average transport duration of 5 h 22 min. Indicators were registered in 237 cows during unloading at the slaughterhouse and in the stunning box. Bruises and condemnations were recorded post-slaughter in the carcasses of the same cows. Results at arrival showed that 48% of the cows had low body condition, 50% had mammary problems, and 24% suffered from lameness. During stunning, 16% of cows needed a second shot, and 54% exceeded the 60 s established as a recommended interval between stunning and bleeding. During the post-slaughter evaluation, 50% of the carcasses had more than two bruises and 70.46% had a bruise severity score different from zero. Low body condition was a risk factor to increase the severity of bruises; low body condition and mammary problems increased carcass condemnations; the stunning process indicators were not statistically associated with the severity of the bruises. For cull cows the main animal welfare issue originates at farm level.