The development of equations to predict live-weight from linear body measurements of pasture-based Holstein-Friesian and Jersey dairy heifers

•In the absence of a weighing scales live-weight of Holstein-Friesian and Jersey heifers can be successfully predicted using body length, heart girth and withers height and their combinations.•Regression equations of live-weight on heart girth, body volume and a polynomial of length, girth, and height equations, respectively, were accurate predictors of live-weight for pasture-based dairy heifers (R² > 0.92 and RMSE < 19.1 kg).•Body volume of the heifer is recommended as the most suitable predictor of live-weight.