Abstract #175

# 175
Development, implementation, and future perspectives of health evaluations in the United States.
K. L. Parker Gaddis*1, P. M. VanRaden2, J. B. Cole2, E. Nicolazzi1, J. W. Dürr1, 1Council on Dairy Cattle Breeding, Bowie, MD, 2Animal Genomics and Improvement Laboratory, Agricultural Research Service, USDA, Beltsville, MD.

The rate at which new traits are being developed is increasing, leading to an expanding number of evaluations provided to producers, especially for functional traits. The objectives of this presentation include discussion of development and implementation of health evaluations in the US, as well as potential future work. Beginning in April 2018, routine official genomic evaluations for 6 direct health traits were made available to US producers from the Council on Dairy Cattle Breeding (Bowie, MD). Traits include resistance to milk fever, displaced abomasum, ketosis, mastitis, metritis, and retained placenta. These health traits were incorporated into net merit indices beginning in August 2018 with a total weight of approximately 2%. Previously, improvement of cow health was primarily made through changes to management practices or selection on indicator traits, such as somatic cell score (SCS) and productive life. Widespread genomic testing now allows for improvement of traits with low heritabilities such as health; however, phenotypes remain essential to the success of genomic evaluations. Establishment and maintenance of data pipelines is a critical component of health trait evaluations, as well as appropriate data quality control standards. Data standardization is a necessary process when multiple sources are involved. Model refinement continues, including implementation of variance adjustments beginning with the April 2019 evaluation. Mastitis evaluations were submitted to Interbull along with SCS for international evaluation of udder health. Possible future developments include multiple-trait models, evaluation of other breeds, and evaluations for additional functional traits such as calf health, feed efficiency, locomotion, or lameness. Future developments will require new and continued cooperation among numerous industry stakeholders. Producers and the dairy industry as a whole must decide how to handle similar evaluations from multiple sources, including proprietary traits from private companies. There is more information available than ever before with which to make better selection decisions; however, this also makes it increasingly important to discern accurate and unbiased information.

Key Words: functional trait, genetic evaluation, health trait