Breeding for resilience in the Netherlands and Flanders
Abstract
Dairy cows could face several environmental disturbances during a lactation like weather conditions
or changes in roughage quality, resulting in reduced functioning. Cows which are minimally affected
by disturbances and/or quickly recover are the preferred cows. Reduced functioning of dairy cows is
measured as the difference in daily milk yield and the expected milk yield for that day. This is called
deviation. The expected daily milk yield is estimated with polynomial quantile regression based on all
milkings of a cow during a lactation. Based on the deviations, two resilience traits are calculated:
stability and recovery. Stability is the natural logarithm of the variance (LnVar) from all deviations
during a lactation, recovery is the autocorrelation (Rauto) between all deviations during a lactation. A
lower LnVar indicates less affection by disturbances, thus more stability, a lower Rauto indicates
quicker recovery. Breeding values are estimated for stability and recovery for lactation 1, lactation 2
and lactation 3 and higher (3+). Heritability (h2
) is 0.09, 0.06 and 0.09 for stability and 0.07, 0.04 and
0.04 for recovery for respectively lactation 1, 2 and 3+. Genetic correlations between different parities
for stability ranges from 0.91 to 0.98 and for recovery it ranges from 0.84 to 1.00. Overall breeding
values for stability and recovery are calculated based on traits in lactation 1, 2 and 3+. An overall
index for resilience is calculated based on the overall breeding values for stability and recovery.
Breeding on resilience results in cows that are less affected by environmental disturbances and recover
quicker. The overall index and the two overall breeding values are the traits that are published in the
Netherlands and Flanders since April 2024.
Key words: resilience, milk yield, variance, autocorrelation, automatic milking system, dairy cow
Downloads
Published
Issue
Section
License
Authors who publish with this journal agree to the following terms:
- Authors retain copyright and grant the journal right of first publication with the work simultaneously licensed under a Creative Commons Attribution License that allows others to share the work with an acknowledgement of the work's authorship and initial publication in this journal.
- Authors are able to enter into separate, additional contractual arrangements for the non-exclusive distribution of the journal's published version of the work (e.g., post it to an institutional repository or publish it in a book), with an acknowledgement of its initial publication in this journal.
- Authors are permitted and encouraged to post their work online (e.g., in institutional repositories or on their website) prior to and during the submission process, as it can lead to productive exchanges, as well as earlier and greater citation of published work (See The Effect of Open Access).
