The response of beef cattle to noise during handling

Noise is often overlooked as a potential source of fear for cattle during handling. Fifty-nine yearling beef heifers (362 +/- 26 kg) were used in a study to evaluate their behavioural and physiological response to noises during a 1-min exposure. In Trial 1, 29 heifers that were naive to the treatments were assigned to either prerecorded handling noise (Noise, n = 14) composed of humans shouting and metal clanging or no prerecorded noise (Silence, n = 15) and tested daily for 5 consecutive days. In Trial 2, the remaining 30 naive heifers were assigned to one of the two components of the Noise treatment, either the prerecorded voices of people shouting (Voice, n = 15) or recorded noise of metal-on-metal clanging (Clanging, n = 15) and again tested for 5 consecutive days. Heifers were tested individually while they were constrained on an electronic scale within a chute complex. Remote telemetry was used to record heart rate (HR). The behavioural response was quantified by an electronic movement-measuring device (MMD). The MMD monitors changes in voltage from the load cells of the electronic scale and records a peak when a trend in voltage is reversed. Heifers exposed to Noise had higher HR (P < 0.01) and recorded more movement peaks (P < 0.05) during the testing period than heifers exposed to Silence. When the Noise treatment was separated into the two components and played hack in Trial 2, the sounds of humans shouting (Voice) appeared to be more alarming, based on HR and movement, than the sounds of metal striking metal (Clanging). Both the HR and the number of MIMD peaks were greater for the Voice heifers (P < 0.05 and P < 0.01). Sounds were played back at equal volumes, therefore some intrinsic differences in the origin or significance of the sounds to the heifers must account for the differences in response. Heifers did show signs of habituation to the noises over the 5-day trials, but it is unknown if cattle would habituate to similar noises encountered during infrequent handling, as is typical with normal management procedures. By eliminating or reducing the sounds of metal clanging and particularly the sounds of humans shouting should help reduce the level of fear cattle experience during handling. (C) 1999 Elsevier Science B.V. All rights reserved.