Roel F. Veerkamp

TL;DR: The implication is that when selection is for a linear combination of milk yield, feed intake, and live weight (i.e., energy balance or efficiency), it is important to consider when each trait is measured during lactation.

TL;DR: Predictions of body energy status from MIR spectral data were considerably more accurate than predictions obtained from the sometimes proposed fat-to-protein ratio in milk.

TL;DR: The heritability of residual feed intake was estimated and heterogeneous relationships between RFI and traits relating to energy utilization were characterized across research stations and care should be taken to allow for potentially heterogeneous variance components and partial relationships between DMI and other energy sink traits across environments when determining RFI.

TL;DR: It was concluded that there probably is some additive genetic variance for the residual feed intake in Holstein cows and measurement of feed intake does provide genetic information additional to that when only production, live weight and live weight change are measured.

TL;DR: Survival to the next lactation (SUV) was analyzed jointly with CIV in a multivariate linear model to account for the selection in CIV data and these traits now form part of the national index for selecting dairy bulls in Ireland.