Inter- and intra-cow variability and the effect of teat-end shape on average milk flow rate, milk harvested in the first two minutes, and seconds below 2.2 lb per minute

Abstract

Data from electronic milk meters that measure milking characteristics such as average flow rate (AFR), amount of milk harvested in the first 2 minutes (2MIN), and seconds below 2.2 lb (1 kg) per minute flow rate (LOW) have been used as indicators of milking efficiency among cows. While these milking characteristics are valuable metrics to optimize efficiency of dairy production systems, the variability in them has not been rigorously investigated. The primary objective of this study was to describe the variability of the milking characteristics AFR (lb/min), 2MIN (lb), and LOW (sec.), both within and between cows. Our secondary objective was to investigate the influence of the explanatory variables milk yield, stage of lactation (DIM), parity, milking time, farm, manual control mode, and teat-end shape on the aforementioned milking characteristics.