Abstract #M35

# M35
Effects of handling before and during processing on behavior and ADG of feedlot steers.
Ruth H. Woiwode*1, Temple Grandin1, Brett Kirch1, John Paterson2, 1Colorado State University, Fort Collins, CO, 2National Cattlemen's Beef Association, Centennial, CO.

The objective of this study was to investigate if a relationship exists between handling, and behavior and ADG of feedlot cattle. Upon arrival at a commercial feedlot in Kansas, Hereford steers (n = 496; initial BW = 304 ± 35.6 kg) of similar genetic background were sorted into 4 pens to determine the effects of handling on behavior and ADG. Two handling conditions before processing and 2 conditions of release from the squeeze chute were imposed. Prior to processing, handlers were required to quietly walk all steers from their home pen to the processing area (SLOW); or handlers were permitted to bring steers to the processing area in the normal fashion (FAST). Individual steers were randomly assigned to one of 2 conditions of release from the squeeze chute. The first was a delay no longer than 30 s following the completion of procedures to allow cattle to stop struggling (DELAY); the second was release immediately following the completion of procedures (NORM). Vocalization, chute temperament, exit speed and exit behavior scores were assigned to all steers during intake processing. Vocalization was scored on a yes/no basis, and was recorded before procedures. Temperament scores were assigned after head gate capture, on a 5-point scale (1 = calm, 2 = shifting; restless, 3 = squirming; shaking squeeze chute, 4 = continuous, vigorous movement, 5 = rearing, struggling violently). Exit speed was scored on a 3-point scale (walk; trot; run), and exit behavior was scored on a 2 point scale with cattle classified as high or low on a reactivity scale (L = No behaviors other than exit speed, H = Stumble, rear, jump). Paired t-tests determined that cattle exiting the chute at a walk or trot vs. a run tended (P = 0.08) to have higher ADG. Cattle vocalizing during restraint had lower (P = 0.04) ADG than those that did not vocalize. The FAST group showed a tendency to vocalize more frequently than the SLOW group. Pearson correlation analysis showed a significant, positive correlation between exit speed and vocalization (P = 0.0021, r = 0.14256), and a significant, negative correlation between exit speed and ADG (P = 0.0036, r = −0.13542). Using this approach, handling was correlated with behavior and ADG.

Key Words: behavior, vocalization, ADG