Claw health and feed efficiency as new selection criteria in the Czech Holstein cattle Krupová Z., Wolfová M., Krupa E., Přibyl J., Zavadilová L

The objective of this study was to calculate economic weights for ten current breeding objective traits and for four new traits characterising claw health and feed efficiency in Czech Holstein cattle and to investigate the impact of different selection indices on the genetic responses for these traits. Economic weights were estimated using a bio-economic model, while applying actual (2017) and predicted (2025) production and economic circumstances. For the actual situation, the economic weights of claw disease incidence were -100.1 € per case, and those of daily residual feed intake in cows, breeding heifers, and fattened animals were -79.37, -37.16, and -6.33 €/kg dry matter intake per day, respectively. In the predicted situation, the marginal economic weights for claw disease and feed efficiency traits increased on average by 38% and 20%, respectively. The new traits, claw disease incidence and daily residual feed intake, were gradually added to the 17 current Holstein selection index traits to improve the new traits. Constructing a comprehensive index with 21 traits and applying the general principles of the selection index theory, a favourable annual genetic selection response was obtained for the new traits (-0.008 cases of claw disease incidence and -0.006 kg of daily residual feed intake across all cattle categories), keeping the annual selection response of the most important current breeding objective traits at a satisfactory level (e.g., 73 kg of milk yield per lactation, 0.016% of milk fat). Claw health and feed efficiency should be defined as new breeding objectives and new selection index traits of local dairy population.