CDCB Health Traits

In April 2018, CDCB launched genetic and genomic evaluations for Holstein males and females, for six of the most common and costly health events impacting dairy herds. These new predicted transmitting abilities (PTAs) are presented as percentage points of resistance above or below the breed average. Larger, positive values are favorable.

As of August 2018, the disease resistance traits will be incorporated into Net Merit and related indexes, for Holsteins, through the new sub-index, Health Trait $ (HTH$), which will not be published separately.

These resources are available to help understand 2018 NM$ and the new health traits.

Net Merit $ 2018

• NM$ 2018: Frequently Asked Questions
• Net Merit as a measure of lifetime profit: 2018 revision, by USDA AGIL

CDCB Health Traits 

• CDCB Health Traits: Frequently Asked Questions
• Individual trait reference sheets
  • Displaced Abomasum
  • Hypocalcemia
  • Ketosis
  • Mastitis
  • Metritis
  • Retained Placenta

• Articles
  • Hoard’s Dairyman article (March 25, 2018 by Dr. Kristen Parker Gaddis), “Genetic evaluations for disease resistance are here”
  • Hoard’s Dairyman article (Jan. 25, 2018 by Dr. Chad Dechow), “Sorting through multiple genetic evaluations for health”
  • Progressive Dairyman (Jan. 1, 2018 by Dave Natzke), “April 2018 Holstein sire evaluations to feature six new health traits”

• Presentations
  • How selection for better health impacts dairy profitability, by Dr. John Cole, USDA AGIL
  • Introducing CDCB health evaluations, by Dr. Kristen Parker Gaddis, CDCB
  • Development of genomic evaluations for direct measures of health in U.S. Holsteins and their correlations with fitness traits, by Dr. John B. Cole, USDA AGIL, at 2017 Interbull
  • Development of national genomic evaluations for health traits in U.S. Holsteins, by Dr. Kristen Parker Gaddis, CDCB, at 2018 World Congress on Genetics Applied to Livestock Production

• Research References
  • Foundational research has been published in several peer-reviewed journal articles, one of which is among the top 100 most highly cited papers published in the Journal of Dairy Science since 2014 (Parker Gaddis et al., 2014). Data editing and validation are based on peer-reviewed methods (e.g., Parker Gaddis et al., 2012).
  • Research references are listed below.
    • Parker Gaddis, K.L., J.B. Cole, J.S. Clay, and C. Maltecca, 2012. Incidence validation and relationship analysis of producer-recorded health event data from on-farm computer systems in the U.S. J. Dairy Sci. 95: 5422–5435
    • Parker Gaddis, K.L., J.B. Cole, J.S. Clay, and C. Maltecca, 2014. Genomic selection for producer-recorded health event data in U.S. dairy cattle. J. Dairy Sci. 97: 3190–3199
    • Parker Gaddis, K.L., M.E. Tooker, J.R. Wright, J.H. Megonigal, J.S. Clay, J.B. Cole, and P.M. VanRaden, 2017. Development of genomic evaluations for direct measures of health in U.S. Holsteins and their correlations with fitness traits (abstract)
    • Parker Gaddis, K.L., J.H. Megonigal Jr., J.S. Clay, and C.W. Wolfe, 2017. Genome wide association study for ketosis in U.S. Jerseys using producer-recorded data. J. Dairy Sci. 101:413-424
    • Donnelly, M. R., A. R. Hazel, B. J. Heins, & L. B. Hansen, 2018. Health treatment cost of Holsteins in 8 high-performance herds. J. Dairy Sci. (in preparation).
    • Liang, D., L.M. Arnold, C.J. Stowe, R.J. Harmon, & J.M. Bewley, 2017. Estimating US dairy clinical disease costs with a stochastic simulation model. J. Dairy Sci. 100(2): 1472–1486.

Photo source: University of Wisconsin-Madison Dairy