PSXVI-19 - Posture behavior and truck microclimate in a very long journey of unweaned dairy beef calves. A field study.

The aim of this study was to characterize posture behavior and truck microclimate of 2 to 8-week-old unweaned calves (59.1 ± 6.72 kg body weight) during 10 transports between December and September (one/month) from an assembly center in Dalry, Scotland to Northern Spain via a control post in Northern Ireland and an assembly center in France (Cherbourg). Average journey time was 105.8 h. A subset of 20 calves per transport were fitted with collars carrying a HOBO environmental logger (HOBO U12) to record the temperature and humidity at calf’ head level and an accelerometer (Axivity AX3) to record accelerations to assess the calf posture (resting, standing or in transition). Data were analyzed with JMP. During the transport, 60% of the time animals were standing, 28% of the time lying and 12% transitioning. Specifically, when the truck was in motion calves spent 82.8% of the time standing, when stationary 68.8% standing, when the truck was on the ferry standing time was 48.4% and at the control post and assembly center standing time was 45.1%.Transports from June to September (n = 4) had an average of 11.96 h (min: 5.17 h; max: 18.8 h) of temperatures greater than 30°C, an average of 25 h (min: 0 h; max: 55 h) of mild heat conditions (72 < THI < 79), and an average of 3.5 h (min: 0 h; max: 23 h) of moderate heat conditions (80 < THI < 89). The exposure to mild and moderate heat conditions occurred mainly during the time that the truck was stationary (waiting at ports) and when calves rested at the control post. Results from this study supports the need to evaluate the impact summer months journeys where animals spend over 30% of the time under heat stress, and the long-standing times on animal welfare.