An observational field study on the effects of changes in shadow contrasts and noise on cattle movement in a small abattoir.

This observational field study examined the effect of changes in shadow contrasts on the floor and noise on balking behavior during handling. Seventy-four Bos taurus beef cattle were observed during handling at a small abattoir. Shadow contrast type (none, soft, sharp) was recorded during three stages of handling (unloading, lairage to single-file alley and into stun box). Cattle balking behavior (stop, put head down, back up) and aversive handling (electric prod, tail twist) were recorded for each shadow contrast type and the presence or absence of a noisy rendering truck. Sharp contrast shadows increased balking behavior compared to soft contrast shadows or none during unloading (X2 = 12.4, P < 0.001). The noisy truck increased balking behavior during handling from the lairage holding pens to the single-file alley (P < 0.001) and during movement into the stun box (P = 0.001). Sharp contrast shadows on the floor from lighting changes and noise from the truck increased balking behavior in cattle.