Are Sire Ranking Indexes Out of Date?

Modern cattle breeding is about creating the future not the past. The dairy cattle breeding industry has reached the stage where yield and ideal conformation should no longer collectively receive the majority of the weighting in total merit indexes? In our current indexes the weights assigned to traits are based on historic happenings. The Bullvine asks the dairy cattle breeding industry to re-consider what is needed in future total merit indexes for milk production focused herds.

Why Consider Changes Now?

Here are five reasons triggering the need for change:

Daughters of the sires used in 2020 will form over half the national milking herd in 2025. On-farm financial margins will remain under significant pressure. There will need to be more required producer guarantees in many areas including animal health, animal welfare, production practices and food safety.
It is predicted that increased consumer demand for milk products will come from higher fat content, A2A2, BB and other speciality products.
In 2025, nowhere near 60% of the cull cows will be removed for production and type reasons. Yet, those two areas account for over 60% of the trait emphasis in today’s total merit indexes.
Herd replacements account for 16% of dairy herd costs yet calf and heifer traits are not included in national total merit indexes.
Dairy farmers and dairy organizations are now placing their emphasis on efficiencies, viability and sustainability, not on high production and type.

Genetics must take these matters into consideration and do its part in creating dairy’s sustainable future.

US Dairy Genetics Report Card on Genetic Progress

CDCB has published the base changes (“April 2020: Genetic Base Changes”) that will occur at the time of the publication of the April 2020 genetic indexes. A synopsis the US genetic progress and implications for the future include:

Farmers have used superior sires which has resulted in very significant progress in milk, fat and protein yields in Holsteins and Jerseys (approximately 93% of the national herd).
Only Holsteins have improved (very slightly) in fertility.
Improvement has been made in PL, yet no improvement has been made in SCS and LIV.
Holsteins have made minor improvement in metabolic diseases.
Final type scores increased for all breeds (+0.10 to +0.76). Most type traits have improved especially udder traits. Short teat length is a problem, especially in Holsteins.
Stature for all breeds continues to increase even though it is widely agreed that there is a need for less stature.
NM$ increased for all breeds. Holsteins and Jerseys increased $231 and$191, respectively, for females born in 2015 compared to 2010.

The genetic advancement pattern in Canada is similar to that in the US. Canadian base adjustments occur annually.

In order to assist dairy farmers to adapt to the April base changes and to quickly know the genetic superiority or inferiority of animals, CDCB, Lactanet/CDN, breeding companies, breeds and other improvement organizations need to more widely publish %RK (percentile rank) or use the technique of an average rating being 100 for a trait.

In summary, the genetic merit of dairy animals has improved significantly with the use by breeders of the current total merit indexes (NM$, CM$, JPI, Pro$, TPI, LPI, …). The challenge before the industry is to develop and implement enhanced total merit indexes that will guide animal selection according to future needs.

Determine Where Your Herd Stands Genetically

For herds genomically testing all their breeding animals, they will know the genetic level for all traits and will be able to use the health, fertility and functionality ratings, when mating the heifers and cows.

Herd owners that are not DNA testing the females they are using to produce the next generation can obtain an approximate level of the females’ genetic merit by averaging the merit of the three nearest sires. An example could be a Holstein sire stack of – Delta x Supersire x AltaIota – this sire stack shows superiority for production, above average for conformation, but in the bottom one-third of the Holstein population for health and fertility. So, herds with that sire stack would benefit by using top of the breed sires for health and fertility.

For Jerseys, a sire stack of Harris x Valentino x Iatola would have production but not health, fertility or longevity. For the sire stack of Vivaldi x Joel x Tequila there is type and A2A2 but not production, longevity or mastitis resistance.

A study of the top twenty-five Holstein sires with the most daughters registered with USHolstein in the first half of March 2020 averaged: TPI – 91%RK; NM$ – 85%RK; PL – 66%RK; SCS – 69%RK; and DPR – 37%RK. This shows that purebred Holstein breeders are using TPI and NM$, but are not as concerned about survival, health and fertility when selecting sires. Of these top twenty-five Holstein sires 72% were A2A2, 32% were daughter proven and 6% transmitted the polled gene.

What’s Holding Back Dairy Cattle Genetic Improvement

Some factors holding back the genetic evaluations for health, fertility and functionality traits include:

An industry attitude appears to persist that having production and type data is all that is needed.
Milking cow health, fertility and functionality data may be captured on-farm, but it is not forwarded to or is not usable at the national central database.
Calf and heifer data are not captured, forwarded to or stored at the national central databases.
Financial herd data is not matched with performance data for all animals (birth until herd removal) and used in management and genetic evaluations.
Future farm revenue needs to include the economic value of fat, protein and other solids and for novel traits – A2A2, BB, … etc. Processor and consumer input needs to be included in determining revenue generation associated with traits. For some dairy farms, now using beef sires, attention will need to be given to growth and health of young stock.
Only a relatively small proportion of animals have their samples submitted for DNA profiling which limits accuracy for management and genetic improvement. Additionally, it limits industry research and development.
When it comes to sire selection, dairy farmers too often use sires that are below average for health and fertility traits. It is a known fact that increased yield is negatively correlated with fertility. There are sires that can improve both simultaneously.

If on-farm data does not reach the national central databases for health, fertility and functionality, dairy farmers can expect to see breeding companies collaborating with cooperating automated herds to capture more of the details. The breeding companies will then develop their own proprietary genetic indexes for ranking their sires.

Bullvine’s Suggested Trait Emphasis

In addition to adding genetic indexes for traits associated with health, labour and revenue, The Bullvine recommends revisions to weightings in future total merit indexes. For discussion purposes, the following areas and emphasizes are provided:

Revenue 30% – Based on ECM (Energy Corrected Milk), A2A2, BB, Meat Sales, Novel Products, …
Durability 20% – Including survival, functionality (mobility, milking ability, calving, …), …
Efficiencies 20% – Including feed conversion, heifer growth, % of lifetime spent milking, …
Health & Fertility 30% – Including reproduction, metabolic diseases, immunity, animal health/welfare, …

Selection Methods Dairymen Can Use Now to Increase Emphasis on Health, Fertility and Functionality

The Bullvine has three suggestion on what dairy farmers can do to put more emphasis on traits beyond production and type:

Select Sires Using DWP$ – At the time of every sire proof release Zoetis publishes DWP$ (overall index), WT$ (cow wellness) and CW$ (calf wellness). Using DWP$ instead of NM$ dairymen can expect 80% of the improvement in production and conformation, but 110% for the improvement in fertility and 200% for the improvement in health.
Select Jersey Sires Using JPI(2020) – In April 2020 USJeresy will publish a revised JPI for all animals that places trait emphasis as follows: Production 49%; Type 20%; Fertility 14%; Health 9%; and Survival 8%.
Modify Selection Using a Current Total Merit Index – In the various sire listings there will be high ranking sires that should not be purchased and used as some of the top sires will not be significant breed improvers for health, fertility and functionality traits. Most breeding companies publish sire lists for their top health, fertility, immunity, robot ready, etc.

Worthy of note is the fact that Holstein and now Jersey breeders have sire indexes for health information on metabolic diseases published by CDCB, Lactanet/CDN and breeding companies.

Dairy Farmers Need to Voice Their Genetic Needs

All dairy farmers need to be making known their future genetic needs when it comes to the genetic merit of their cattle for health, fertility and functionality traits. The industry including breeding companies, bull-breeders, genetic evaluation centers, on-farm data capture organizations and breeds needs to listen and to revised total merit indexes.

The Bullvine Bottom Line

The time has arrived where dairy cattle owners need to have more animal genetic information for health, fertility, functionality and survival traits. As well, predictions need to be made on how revenue will be generated from dairy herds in the future and the effect those revenue sources will have on genetic indexing. Now is the time to include the entire lifetime of animals, covering both revenue and costs, in total merit indexes. Now is the time to create new total merit indexes that best serve milk production focused farms. Now is the time!