Health Traits

for dairy cattle

Breeding for a Healthier Herd

Healthy cattle that transition well, breed back easily and last in the herd positively impact your bottom line. For that reason, GENEX is and always has been dedicated to ongoing genetic improvement in health traits. This dedication led to the development of GENEX proprietary health traits based on data-driven innovation.

Today GENEX publishes two Jersey-specific proprietary traits: Age at First Calving (AAFC) and Calf Survivability (CSRV). Both are incorporated into the ICC$™ index for Jerseys to help you breed healthier herds of ideal progressive commercial cows.

Photo of cattle in fence

Age at First Calving (AAFC)

AAFC highlights the importance of daughter fertility within the Jersey breed. Lowering age at first calving has a positive impact on profitability through improved fertility, higher milk production and limited impact on stillbirths. Therefore, breeding for heifers that calve at a proper age at first calving equals bottom-line profit.

What you need to know …

  • The breeding value is set to a base of 100.
  • Higher values indicate a sire’s daughters grow and mature faster, becoming reproductively viable at a younger age.
  • You can expect about a 44-day difference in age at first calving between daughters of a 105 AAFC sire and daughters of a 95 AAFC sire.
  • The breeding value has a 18.7% heritability.
  • AAFC is a component of the Fertility (FERT$) sub-index of the ICC$™ index for Jerseys. To improve herd fertility, choose sires based on the ICC$™ index and then the FERT$ sub-index.

Calf Survivability (CSRV)

This health trait brings awareness to genetics that instill hardiness and survivability in newborn calves, which is a continual area of concern for Jersey producers. Demonstrating its significance, the GENEX research database shows  approximately 6.5% of Jersey calves die between days 2 and 120 of age.

What you need to know …

  • The breeding value is set to a base of 100, with higher values more desirable.
  • It reflects the percent of female calves that survive past 120 days of age (excluding calves sold).
  • You can expect about a 5.5% difference in calf survivability between daughters of a 105 CSRV sire and daughters of a 95 CSRV sire.
  • CSRV is based on Jersey-specific information in the GENEX research database which totals 54 million health records on nearly 12 million cows.
  • CSRV is a component of the Sustainability (SUST$) sub-index within the ICC$™ index for Jerseys.
For the best website experience, we recommend you download Chrome or Edge.  Simply click the icon of your choice on the left to download.