Joe Binversie, Value Added Programs Manager, Genex
It's easy to say that genetics matter, but how do you know for sure on the herd level?
Determining the Value & Impact of Genetics
A couple times a year — maybe after each sire summary — you determine which artificial insemination (A.I.) bulls to use on your cows and heifers. You usually choose sires based on some predetermined genetic criteria. In other words, you choose sires based on the index or traits you feel will take your herd in a profitable direction. But how do you know those genetics are making a difference? Is your herd making genetic progress? Is your herd deficient in certain genetic traits, and are there implications on herd performance as a result? Should you move your focus to other genetic traits?
A genetic analysis is a great way to evaluate and verify that the quality of genetics you have chosen is actually making a significant impact on your herd, and Genex is here to help. The Results and Profiler programs were designed to give you ban inside look at genetic performance and progress. Both compare genetics within a single herd. (For those interested in comparing their herd's genetic averages to benchmark herds, that analysis is offered through the Dairy Performance Navigator™ program.)
Learning from Results
Daughter Pregnancy Rate (DPR), the percentage of nonpregnant cows that become pregnant during each 21-day period, is one of several traits where genetic performance can be analyzed for your herd. Figure 1 shows the effect of DPR on average days open within a single herd.
What does Figure 1 say? It sorts all pregnant cows (milking and dry) by their sire's predicted transmitting ability (PTA) for DPR. Among the sires of the herd's pregnant cows, the top 25% for DPR average +2.79. The bottom 25% of sires of pregnant cows average -0.88 DPR. That's a difference of 3.57!
Now, how do those sire PTAs equate to actual performance (days open) among their daughters? Daughters of the top quartile DPR bulls averaged 123 days open with a 396-day calving interval. Daughters of the bottom quartile DPR bulls averaged 153 days open with a 419-day calving interval. Genetics are making a difference in this herd: higher DPRs are leading to 30 fewer days open and a shorter calving interval. That has to impact herd profitability.
Figure 2 examines the dollars and cents of DPR. Assuming each extra day open costs an additional $3 per cow per day, daughters of the top quartile bulls have a $90 per cow per year advantage over daughters of the bottom quartile sires. For this herd, in its entirety (534 pregnant cows), that equates to an $11,520 advantage.
In this herd example, it is easy to see genetics do matter. This validation of the impact of genetics on an individual herd comes from the Genex Results™ program. in addition to DPR, Results compares actual cow performance to their sire's PTA for Milk, Fat, Protein and Somatic Cell Score. Financial implications (profit or loss) of these performance differences are included as well.
Profiling Herd Genetics
If you are looking for a more expansive genetic analysis of your cows and heifers as well as current service sires, Genex offers Profiler. in comparison to Results, Profiler offers more options and is fairly customizable.
Let's use Profiler to examine the impact of PTA Stature within a single herd. Figure 3 shows all cows and heifers according to their sire's PTA for Stature. Each dot represents an individual animal. The graph shows this herd changed their genetic selection criteria by selecting for shorter statured sires, as shown by the dots in the red box representing heifers. Said another way, you can see a significant drop in sire PTA Stature when going from first lactation cows (blue dots) to heifers (red dots).
Why did the dairy producer in this example decide to begin choosing smaller statured sires? Likely the decision was based on several reasons, but one may have been another Profiler analysis. Table 1 shows the production performance implications of cows between 60 and 305 days in milk by their sire Stature.
You can see the top 50% (taller cows) and bottom 50% (shorter cows) have very comparable milk production as shown by the average 305-day mature equivalent. However, when evaluating average Energy Corrected Milk (ECM), you see the bottom 50% of cows is greater in comparison to the top 50%. ECM is a way to compare production on a level playing field due to the three moving parts (volume, fat and protein). Tracked over time, ECM can help to give an accurate indication of cow and herd performance, and in this instance, the impact of sires' PTA for Stature.
in addition to these analyses, Profiler provides numerous genetic reports. This includes options such as determining the impact of genetics on herd health events (i.e., effect of Lifetime Net Merit on recorded incidences of displaced abomasums, retained placentas, metritis, mastitis, etc.).
Results and Profiler continue to evolve. In fall 2015, Results will also include the Ideal Commercial Cow (ICC$) index. This will offer you the opportunity to evaluate ICC$ within your own herd and to see its impact. Likewise, additional reports are planned to be added to Profiler as well. In summary, Results and Profiler offer great opportunities for producers to determine the value and impact genetics have in their own herd.
Results: Herds using Dairy Comp 305 or PC Dart herd management software and/or herds on DHI test are able to utilize Results. Results reports are generally most effective with at least 150 to 200 sire-identified cows; this provides greater power and confidence in the analysis. Analysis is also included on cows lacking a valid NAAB code for their sire ID (i.e. cows with missing or wrong sire identification or sired from natural service). Results is run by the Genex Value Added Programs staff and may be requested through your local Genex representative.
Profiler: Reports are generated by Genex consultants and are currently available to herds using Dairy Comp 305 herd management software. If interested in these reports, contact your local Genex representative.