Archive for Net Merit

The New Net Merit Formula – The Winners & The Losers

For over twenty years USDA-AIPL and now CDCB have been publishing Net Merit (NM$) values for dairy cattle with US genetic evaluations.  Over those twenty years five revisions have been made to the formula, the last in 2010, as new traits have been added, new genetic evaluation methodologies have been developed, and the economics of dairy farming has changed. The next change in the formula will occur in December 2014.

It is important that breeders consider the impact of the coming changes as they review the sire, cow and heifer NM$ indexes on August 12th.  Breeder consideration is needed because the matings that are made this fall will have offspring born in 2015 when the new formula will be in place. Obviously the changes in the formula will not affect how the new future animals will perform but it will, however, affect where the animal ranks for marketing purposes and where a herd’s genetic level for NM$ is relative to other herds.

Let’s dig deeper and see what changes are to take place and how that may affect current breed leading NM$ sires.

Significant Changes Coming In December

The following table compares the weightings, 2010 to 2014 (December), for the components of the NM$ formula.

TABLE 1: Comparison of Relative Emphasis for Traits in NM$ Index

NameLbs. MilkPLSCSCENM$PTATUDCF&L CTPI
DE-SU OBSERVER-ET16027.22.7667922.73.020.892332
HONEYCREST BOMBAY NIFTY-ET2367.22.627553-0.46-0.130.971810
POTTERS-FIELD KP LOOT-ET10047.22.6876500.081.71-0.241954
KELLERCREST BRET LANDSCAPE817.12.3685060.651.271.161838
WHITMAN O MAN AWESOME ANDY2026.92.5557540.32-0.171.212063
ZIMMERVIEW BRITT VARSITY-ET4106.82.6266680.71-0.471.552013
CLEAR-ECHO NIFTY TWIST-ET9426.82.628748-0.32-0.421.172039
KED OUTSIDE JEEVES-ET3556.82.83105151.370.971.741913
ENSENADA TABOO PLANET-ET22166.72.9867211.931.44-0.472176
GOLDEN-OAKS GUTHRIE-ET10786.72.786535-1.15-1.240.361728
DALE-PRIDE MANFRED ALFIE5196.62.966461-0.63-0.36-0.011702
LAESCHWAY JET BOWSER 2-ETN2006.52.8474551.622.031.831940
ELKENDALE DIE-CAST-ET-8726.52.7263700.681.851.991718
LAESCHWAY JET BOWSER-ET2006.52.8474551.622.031.831940
BADGER-BLUFF FANNY FREDDIE12366.42.757791.571.62.872292
CABHI AUSTIN POTTER-ET1516.42.8165200.050.410.021766
CABHI MOOSE-ET456.42.6463730.180.31.111625
SILDAHL JETT AIR-ET11186.32.6466442.882.262.912168
SPRING-RUN CAMDEN-676.22.9174330.571.790.61762
KERNDT MAXIE GOLDSTAR-ET1996.22.576449-1.28-0.61-0.961631
 

Thoughts on the changes include:

3 Proven Sires Favored by New Formula

Three currently (April 2014) high NM$ proven sires will gain from the new formula. They are: Roylane Socra Robust; Den-K AltaGreatest; and Mainstream Manifold. They are all high production sires, and the new formula will favour them. All three, Robust, AltaGreatest and Manifold will also benefit from less emphasis on their average traits – SCS and DPR.

Breeders can expect to see sires that have production indexes below 1500 lbs for milk and 65 lbs for fat drop relative to other sires for NM$. Sires over 2200lbs milk, 80 lbs fat and 55 lbs for protein will rank higher for NM$ come December 2014. Breeders that use NM$ in sire selection should consider discontinue using, after August 12th, sires with low production indexes.

2 Genomic Sires Going Up!

Two currently (April 2014) high NM$ genomic sires will be rated higher with the new formula. They are: Cogent Supershot; and Uecker Supersire Josuper. They are outstanding for production. Supershot – 2528 lbs milk, 100 lbs fat and 85 lbs protein. Josuper – 2971 lbs milk, 118 lbs fat and 92 lbs protein. Supershot has good ratings for the other traits so will remain to standout for NM$. Josuper will benefit from less emphasis on traits where he is breed average.

Many current relatively high ranked NMS genomic sires will fall back if they have only moderate milk indexes.  Breeders should consider discontinuing the use of genomically evaluated sires below 1600 lbs milk, 85 lbs fat and 60 lbs protein.

The Effect on Polled Sires

Current marketed polled proven sires are not highly rated for production, so will not fair well with the new NM$ formula. On the genomic sire side, two high production sires standout as sires that should increase in their relative NM$. They are Bryhill Socrates P (1914 milk 99 fat and 65 protein) and Pine-Tree Ohio Style P (2033 milk, 64 fat and 57 protein). Other sires that will do relatively well under the new NM$ formula are Kerndtway Eraser P, Da-So-Burn MOM Earnhardt P and Pine-Tree Ohare P.  Many polled sires have below 1000 lbs of milk and can be expected to drop significantly in NM$ come December.

1 Star Sires of Sons

One sire of sons stands out as benefiting, in a significant way, from the new NM$ formula. That sire is Seagull Bay Supersire. His high production numbers put him in an elite status – 2434 lbs milk, 111 lbs fat and 78 lbs protein. The reduced emphasis on SCS and DPR, in the new formula, will also help Supersire, as he is average for those traits.

Other genomically evaluated sires of sons, heavily used over the past couple of years, often have been only moderately high for production traits. Included in this category are sires such as Mountfield SSI Dcy Mogul, De-Su BKM Mccutchen and Amighetti Numero Uno. These sires do have some outlier high production rated sons but, on average, the majority of their sons will drop for NM$ come December.

Be Prepared to Avoid Inbreeding

With both Robust (sire) and Supersire (son) in heavy use and both benefiting from the new NM$ formula, it will require that top outcross sire and female lines be identified and used in order to avoid inbreeding. That can be accomplished by breeders using both corrective mating and genomic testing.

The Bullvine Bottom Line

The changes coming for the NM$ formula in December 2014 are not just minor tweaks. Breeders that use the NM$ index in sire selection should be prepared to set aside sires that in the past have had high NM$ ratings but were only average to slightly above average for their production indexes.


The Dairy Breeders No BS Guide to Genomics

 

Not sure what all this hype about genomics is all about?

Want to learn what it is and what it means to your breeding program?

Download this free guide.

 

 

 

Canadian LPI Rescaling Explained (April 2013)

Understanding and correctly using genetic indexes is important to breeders who derive a significant portion of their profit from dairy cattle breeding decisions. Major changes in the expression of indexes do not occur frequently but when they do occur it can be a time of confusion and perhaps lack of trust. The Canadian total index, LPI, has been used for over twenty years by Canadian breeders, as well as by breeders from other countries who source genetic material from Canada. When changes occur in the LPI indexing system, as is the case just now in April 2013, it is important that the reasons for the changes and the results be understood and incorporated into breeders’ decision processes.

Why Change?

For some time now the LPI values, especially for Holsteins, have been increasing quickly for all animals but it has been most noticeable for animals that have genomic evaluations. Breeders questioned how these young animals with indexes that are about 65% reliable can be significantly superior to recently proven top end bulls and active cows with their own performance values. As most breeders refer to the absolute LPI number, significant differences between the leaders on the various listings left doubt in accuracy in breeders’ minds. For breeders who think is bottom line terms and do not follow the LPI numbers closely, comment were often heard about the fact that numbers are numbers but it is annual cow profit that pays the bills, expands the business and sends the kids to college. Point being that the LPI difference between animals over-stated the net dollar difference between animals. These questions, comments and concerns were heard loud and clear by the CDN’s Genetic Evaluation Board so it studied the matter and took action.

LPI Scaling

The extreme range (-3500 to +3500) in Canadian Holstein LPI values had many drawbacks. It assigned most older long-lived profitable cows a negative value thereby telling a story that was not true and limiting the saleability of their subsequent generation. It assigned values that indicated significant differences between animals when the actual dollar differences were not that large. And due to the scaling effect for animals at the very top of the breed it gave values far exceeding the actual differences.  This latter point was especially true for bulls and heifers with only parent averages and genomic evaluations.

While studying possible solutions, CDN noted that in other major dairy breeding countries the scale for their total merit index is much much smaller than Canada’s 7000 point range. CDN decided to adopt a publication methodology for the LPI similar to what the TPI™ has used for many years. That involves calculating a value and adding a ‘constant’ to it.

New LPIs

Effective April 09, 2013  the new LPI formula is ½ Previously calculated LPI  + Constant.

cdnfigure1

Note that the highest progeny proven sires do not change in value.

currentvsnewlpi

Note that the range in values of Holstein LPIs is now much more similar, although slightly more, than the range for  Holstein TPI™

Sire LPIs

It is important to note that this re-scaling of LPI does not re-rank animals. But it does bring the progeny proven sires and genomically evaluated young bulls much closer in their values.

toplpigenomicsiresdec2012

It is important to remember that LPI is the Canadian system for ranking animals according the weights assigned to the numerous genetic indexes of important for lifetime profit. For Holsteins the weights at 51% Production, 34% Durability and 15% Health and fertility while for Jerseys those weightings are 57%, 33% and 10% respectively. Breeders wanting to place more or less emphasis on the various can calculate their own rankings using  the CDN calculator available at www.cdn.ca or going the Bulvine’s bull listings for alternative ranking systems (Read more: Bullvine Performance Index (BPI) – Top Sires December 2012).

Using Genetic Indexes

Indexes are a very constructive tool to genetically breed better animals for the future. As genetics is less than half of the reasons animal differ in profitability, much depends on breeders to not only produce the animals that will be profitable but also to feed and manage them.  Some suggested ground rules to follow when making sire or heifer selections are:

  • Use LPI, TPI™ or Net Merit are you primary list reduction tool for sires or herd replacements
  • Always check out the index values for the traits important to you (i.e. protein, fat, feet & legs, udders, SCS, fertility,..). Eliminate animals from the list that do not meet your requirements.
  • A quick way to eliminate animals is to use % RK (percentile rank).
  • Animals below 75% RK for any yield or conformation traits will likely leave progeny that reduce your profit.
  • Animals below 60% RK for health and fertility traits will not move your herd ahead for these traits of emerging importance.

The Bullvine Bottom Line

Even though the method of expressing genetic indexes may differ from trait to trait or country to country, it is always important to have a plan on what you want to improve genetically  in your herd and then to select the sires or replacement females that will produce the results. The re-scaling of the LPI values will come closer to the actual dollars amount animals return in their lifetime profit and will more accurately compare older and younger animals. By all means keep your genetics current and on target to your needs. It is best to throw out the semen from low indexing bulls. Buy high ranking genetics. It always pays big dividends.

 

Get original “Bullvine” content sent straight to your email inbox for free.

 

Send this to a friend