A total of 1,488 pigs were transported to slaughter using a mechanically-ventilated vehicle in the winter in Canada. On each of six journeys, a sub-sample of 78 pigs were randomly assigned to two space allowances (0.46 or 0.53 m2/pig), distributed across six compartments, in two positions (near-front and near-rear) and three deck levels (top, middle, and bottom). Compartment ambient conditions (e.g., T°C and RH%) were monitored during transport and pig behaviour was recorded during lairage. Blood lactate, hematocrit, creatine kinase (CK) concentrations and meat quality in the longissimus (LM), semimembranosus (SM), and adductor (AD) muscles were assessed on a total of 108 pigs. Pigs transported at 0.53 m2/pig had greater blood hematocrit levels (P = 0.05), but lower blood CK concentrations at slaughter (P = 0.01). The top deck was colder during all transport events (P < 0.001), and pigs transported in this location stood less in lairage compared to those transported on the bottom deck (P = 0.05). Pigs from the top deck showed lower L* values in the LM and SM muscle (P = 0.02 and P = 0.04, respectively). Overall, animal location had a greater impact than space allowance on animal welfare and meat quality of pigs.
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