Intensity of oestrus signalling is the most relevant indicator for animal well-being in high-producing dairy cows.

Full signalling of oestrous behaviour is vital for proper timing of AI and good reproductive performance, currently jeopardized by shorter observations of oestrus behaviour. Alternative indicators including progesterone (P(4)) recordings on-farm are tested. Oestrous intensity of 37 heifers (H) and 30 1st-parity dairy cows (C(1)) either Swedish Red (32) or Swedish Holstein (35) with high genetic potential for milk production, was studied in relation to AI.