Schnaider, M. A., Heidemann, M. S., Silva, A. H. P. et al. 2022. Vocalization and other behaviors as indicators of emotional valence: The case of cow-calf separation and reunion in beef cattle. Journal of Veterinary Behavior 49, 28-35.
Vocalization may communicate the emotional state in vocal animals. We aimed to describe and compare vocalization and other behavioral signs of cow-calf pairs in emotionally negative and positive situations, and the potential influence of genetic group, parity category and calf sex on these signs. Forty-two beef cows (16 primiparous and 26 multiparous), and their 24 h-old calves (24 males and 18 females), with no previous separation from their mothers, were studied in Southern Brazil. The dams were daughters of Taurine crossbred mothers, 16 with Limousin (LIMO), 15 Charolais (CHAR), six Brahman (BRAH) and five Blond d'Aquitaine (BLON) bulls. We recorded 3 minute-videos to analyse animal responses to three sequential treatments: AR – arrival of cow and calf together in corral one (C1); SE – separation of the pair, calf removal from C1, isolated in corral 2 (C2), not seeing but hearing the cow; RU – reunion of calf and mother in C1. For cows and calves, the vocalization count per minute, fundamental frequency (f0), duration of the vocal call and latency to vocal response in AR, SE and RU were measured, as well as selected behaviour signals. A significant interaction effect between treatment and genetic group was observed for duration, pitch and vocalization count per minute. In SE, LIMO and CHAR cows expressed longer vocal responses than during AR, 24.6% and 18.2%, respectively, and RU (LIMO 15.7% and CHAR 33.6%). In SE, LIMO (114.2Hz) and BRAH (124.6Hz) cows showed higher f(0). CHAR and BRAH cows vocalized 2.8 and 5.1 times more frequently during SE than RU. Cows showed higher frequency of tail movements and smelling the corral in SE than in AR and RU. Cows presented higher frequency of head movement in SE as compared with RU. Calves showed greater head and body movement during SE than during AR and RU. In SE, male calves showed higher frequency of ear movements than female calves. Body movements of the cow were also more frequent during SE than in RU. Overall, cows showed higher pitch, longer vocal calls and other behavioral changes in SE, such as tail flapping, sniffing the corral, and head and body movements; calves showed higher frequency of head and body movement in SE. The results suggest that the studied indicators may be useful to identify emotionally negative situations, with genetic group and calf sex as factors which deserve further studies.