While it may not dominate headlines or industry top 100 lists, genetic diversity plays a critical role in protecting herd performance, minimizing risk and preserving future opportunities. In today’s dairy environment, genetic diversity is not optional. It is a herd’s insurance policy.
What is genetic diversity?
In practical terms, genetic diversity refers to the number of different bloodlines represented within a herd or within a genetics company’s breeding program. It is influenced by how many different sires are used, how closely related those sires are and how much overlap exists at the maternal grandsire and great-grandsire levels.
A genetically diverse plan does not ignore genetic merit or consistency. Instead, it balances strength in key traits with enough variation to maintain consistency and reduce the risk of inbreeding. When genetic plans become concentrated around a small number of bloodlines or a single elite sire, herds become more exposed to risks from inbreeding, industry re-rankings, fertility concerns and genetic defects.
Why does genetic diversity matter more today?
Several industry trends have increased the importance of monitoring and protecting genetic diversity.
First, the average dairy herd size continues to increase. Larger herds amplify both the upside and downside of genetic decisions. A single widely used sire can influence hundreds or thousands of cows within a few years, increasing exposure if issues arise.
Second, the shift toward genomic sires over proven bulls remains true globally. While genomic evaluations are powerful tools, this shift does magnify the need to use a greater number of bulls due to the slightly lower reliability of genomic sires. When herds or breeding programs rely too heavily on a narrow group of young genomic bulls, the impact of re-ranking – or unexpected weaknesses – can be significant.
Third, the large adoption of genetic protection within the dairy industry has limited access to elite germplasm, except for within a stud’s own genetic nucleus. This industry change has caused and will continue to cause the narrowing of genetic bases over time, making it even more important for genetics companies to identify other ways to incorporate diversity into their genetic portfolios.
When analyzed all together, these factors mean that genetic diversity now plays an important role in supporting genetic progress in the industry while protecting producers from unknown volatility and risks.
Why should genetic companies value diversity as much as dairy producers?
Producers focus on managing inbreeding or sire usage at the farm level, but the diversity embedded within a genetics company’s breeding program is just as important. The choices made upstream directly affect the options, flexibility and risk exposure that happens downstream.
Breeding programs that focus on marketing a single genetic line may generate many sons on industry ranking lists, but this approach concentrates and compounds risk for producers. Balancing consistency and diversity in sires is important to ensure the genetics offered to dairy producers help them reach their goals and avoid risks from inbreeding. Consistency of sires in a stud’s genetic planning allows producers to create a more uniform herd for priority traits, increasing herd performance and profitability, but there is also a need for diversity.
Genetic diversity within a company’s genetic plan protects producers in several ways.
- It minimizes the risk of any single sire re-ranking or dropping significantly. A single bull can drop more than expected as more data becomes available, so tying into a specific bull or sire line can intensify the effect. Today, using four genomic sires creates a bull group average of 95% Reliability, which is the same level as those highly proven sires who were coveted 15 years ago.
- It maximizes pregnancy production by lessening fertility influences. Bulls are biological creatures, and even with tight lab and process controls, there are differences in semen fertility. By using more sires, we lessen the overall fertility influence of a particular bull and spread out breedings over more semen collection days. This helps producers avoid putting their herd’s proverbial eggs in one basket for creating calves.
- It reduces the potential of uncovering hidden haplotypes. Every animal, even a human, carries half a dozen individual genetic defects. While not concerning by itself, concerns arise when a sire becomes popular and prominent in a breed – the curse of popularity. It only takes a few generations before a popular sire’s offspring inadvertently get mated to each other, and hidden haplotypes are uncovered. Genetic diversity minimizes the impact of individual recessives.
How does genetic diversity at the stud level impact producers?
While this doesn’t apply to everyone out there, forward-thinking companies have taken intentional steps to preserve diversity, while increasing selection intensity. Because of this commitment from several companies, farmers can trust those genetics to help them:
- Minimize the risk of future unknowns
- Mitigate fertility influence on-farm
- Worry less about a sire re-ranking
- Reduce the fear of haplotypes
- Manage inbreeding at the farm level
- Increase the return on their investment
- Make faster genetic progress
- Reach their dairy’s specific goals
- Maximize profitability and promote sustainability
What can producers do to maintain diversity in their herd?
Protecting genetic diversity is not solely the responsibility of genetics companies because producers play a critical role through their genetic plan. Fortunately, maintaining diversity does not have to come at the expense of genetic progress.
To ensure diversity in your genetic plan, incorporate four to six sires in your genetic plan for each sire summary, with no more than two having the same sire. This ensures adequate genetic diversity to minimize genetic re-ranking, future haplotype exposure and potential semen fertility impacts. Ask your genetic partner to help you manage genetic diversity.
As genetic progress continues to accelerate, the responsibility to advance genetics in a thoughtful, sustainable way has never been more apparent. For today’s dairy producers, working with partners who value and actively manage genetic diversity is one of the most effective ways to protect your profitability and sustainability. Genetic diversity is not about slowing down progress; it is about protecting it, creating an insurance policy for lasting genetic progress. Can you afford to ignore genetic diversity?
