Bioacoustic tools for enhancing animal management and productivity: effects of recorded calf vocalizations on milk production in dairy cows

Abstract

Vocal communication mediates social relationships in many mammalian species and can be particularly important in mother–infant interactions. Mammalian species in general and cows in particular exhibit a strong mother–infant bond that is frequently expressed through vocal exchanges among mothers and their infants. Several species produce calls that are exclusively used to induce nursing behavior. We therefore predicted that calf calls would affect the behavior and biology underlying lactation in dairy cows. Playback of calf vocalizations were conducted at two dairies under controlled conditions. Exposure to calf vocalizations significantly increased milk production in experimental cows by 1–2% in the milking session immediately following the milking session in which playbacks were conducted. The playback of calf vocalizations in the milking parlor therefore increased overall milk production (but not immediate milk release or letdown) in dairy cows. These data suggest that the use of calf vocalization playback as a bioacoustic tool provides a non-chemical alternative for increasing milk production in dairy cows.