Lying behaviour of lactating dairy cows in a cow-calf contact freestall system

Conventional dairy farming practices usually involve early separation of calves from their dams. Cow-calf contact (CCC) systems may offer an alternative rearing solution that allows for the expression of natural behaviours, such as suckling and bonding. However, literature exploring the effects of CCC systems on lying behaviours of lactating cows is limited. Thus, the aims of this study were to assess: (1) the lying behaviours of lactating dairy cows with and without access to a CCC area, and (2) freestall use and lying patterns of cows and calves with access to a CCC area over a 14-week suckling period. Cow-calf pairs (Swedish Holstein: n = 15; Swedish Red: n = 25) were assigned one of two treatments after calving: dam-calf contact rearing (full contact; FC, n = 19), where calves were housed in a CCC area in the same facility as their dams, or separation shortly after parturition (no contact; NC, n = 18). The CCC area contained stalls and concentrate feeders which only FC cows had access to. Daily lying time - as well as the duration and frequency of lying bouts - was collected for cows automatically using leg-mounted tri-axial accelerometers. Video recordings were also collected and used to perform scan sampling of cow and calf lying location at 10-minute intervals for a 24-hour period each week. Behavioural data was collected during 14 weeks, starting when all cow-calf pairs had entered the experimental pen and continuing until separation. Access to full CCC did not affect daily lying time nor the frequency of lying bouts. Overall, mean daily lying time increased with stage of lactation. Lying bout duration and frequency were affected by an interaction between stage of lactation and parity, with the frequency of lying bouts decreasing as lactation progressed, but only for primiparous cows in post-peak lactation. Average bout duration increased with stage of lactation for primiparous cows, and from early to post-peak lactation for multiparous cows. Moreover, there was an interactive effect of treatment and parity on lying bout duration, with multiparous FC cows performing longer bouts than primiparous FC cows. FC cows spent 77.3(28.4)% (mean(SD)) of their total lying time within the CCC area across all weeks. These results combined indicate that lying behaviour in this CCC system was likely influenced by factors other than CCC. Furthermore, cows with access to CCC maintained their individual patterns of stall use throughout the suckling period investigated in this study.