The Next Generation

Replacements determine the future success or failure of every dairy operation and the cost of raising replacements is one of the most significant drivers of net farm income. The average cost of losing a replacement in the USA is $500, or about half the cost of fully raising a heifer. This does not account for the genetic potential of the animal and the opportunity cost of losing a heifer that was intended to build the next generation. Even if mortality rates are low, disease incidence in the early months of life negatively impacts growth rates and reduces lifetime production. However, until recently genetic evaluations focused almost entirely on mature animals, with little attention given to the genetics associated with the early months of a dairy animal’s life. CDCB HLIV and Zoetis Calf Wellness evaluations offer dairy producers a means to genetically improve calf health and livability, enhancing animal welfare and reducing economic losses. 

Calf Wellness

According to the National Animal Health Monitoring System (NAHMS), the leading causes of mortality in calves are scours (diarrhea) and respiratory disease. Proper feeding of colostrum, hygiene, vaccination and nutrition play critical roles in raising healthy calves. However, management does not explain the differences in disease rates among calves raised in the same environment. Not surprisingly, there is a genetic connection to disease resistance! Over the past 10 years, Zoetis utilized millions of calf health records along with genomic testing to develop genetic evaluations for resistance to scours and respiratory disease. These traits are included in the Zoetis Calf Wellness Index (CW$), which associates economic values with the genetic contribution of these traits to an animal’s lifetime profitability. 

Recognizing the differences in disease incidence by breed, Zoetis utilizes different formulas to calculate CW$ for Holsteins and Jerseys. This allows for maximized genetic progress when selecting for improved calf wellness in each breed.

Livability

There are two heifer livability evaluations: CDCB Heifer Livability (HLIV) and Zoetis Calf Livability. The HLIV evaluation is based on data collected between 2009 and 2016 from over 3.4 million heifers of all breeds. 4% (135,000) of the heifers were recorded as having died between two days and 18 months of age. Heifers that died prior to two days of age were considered stillborn and included in stillbirth evaluations.

HLIV is expressed as a percent livability above or below breed average (96% for Holsteins and Jerseys), with higher numbers indicating higher livability (less death loss). Zoetis Calf LIV is expressed as a standardized transmitting ability (STA), with 100 as the mean. Values above 100 indicate improved livability compared to average.

Summary

CDCB HLIV and Zoetis Calf Wellness evaluations are available for both Holsteins and Jerseys and may be available for other breeds in the future. The Zoetis Calf Wellness traits are included in the Dairy Wellness Profit Index® (DWP$®) and HLIV will be incorporated into NM$.

The success of every dairy is closely tied to the success of the replacement heifer program. When combined with best management practices, including heifer livability and calf wellness traits in your herd’s genetic selection index will help to improve the health and quality of your next generation of heifers.

References

CDCB. Heifer Livability. https://www.uscdcb.com/wp-content/uploads/2020/10/Microsoft-Word-Heifer-Livability-Coming-in-December10_2020-Heifer-Livability-Coming-in-December-10_2020.pdf November, 2020.

CDCB. Heifer Livatility Trait Reference Sheet. https://www.uscdcb.com/wp-content/uploads/2020/11/CDCB-Reference-Sheet-HeiferLivability-12_2020.pdf November, 2020.

Zoetis CLAIRIFIDE Plus website. https://www.zoetisus.com/animal-genetics/dairy/clarifide/clarifide-plus.aspx

®Dairy Wellness Profit Index (DWP$) is a registered trademarks of Zoetis Inc., its affiliates and/or its licensors.

™Calf Wellness Index and CW$ are trademarks of Zoetis Inc., its affiliates and/or its licensors.