Genetics - the long-term solution
Research and innovation driving genetic gain for improved productivity and performance in our dairy cattle, has been the focus for many years of the research out of the DairyBio Animal program.
In recent years this focus has included how we produce a more environmentally sustainable cow in the long-term with recent Breeding Values released around Heat Tolerance, Feed Conversion Efficiency and work underway on Methane Emissions.
These Breeding Values harness the power of genetics to help improve the performance of dairy cows, without burdening farmers with significant system changes or expensive capital investment.
Herd Fertility Cumulative Improvements
A consistent selection for fertility traits when making breeding decisions, leads to a permanent and cumulative improvement of reproductive performance in dairy cows.
Genetic selection for fertility, using the daughter fertility Australian Breeding Value (ABV), that is currently available, provides the opportunity to improve fertility in a way that is relatively simple.
According to PhD candidate Ee Cheng, “The current fertility ABV in use is based on multiple traits, rather than just one. This means that we can make progress in multiple aspects of cow fertility. Traits included to help determine the fertility ABV include calving interval, lactation length, days to first service, non-return rate and pregnancy rate.”
“We know using this multi-trait ABV has meant that the mean fertility of heifers has increased since its introduction in 2013.” Continues Ee Cheng
Ee Cheng did point out that, “While the InCalf program was only able to pinpoint genetics as a key driver of fertility, we must remember that daily management decisions can affect a cows ability to reach her fertility potential.
Overall herd fertility is a complex web of both daily, weekly, monthly and yearly decisions.”
Climate and Heat Tolerance
Beyond what we can do within the environment on-farm, genetic selection can also help ensure our cows are ready for future climates.
As we are in summer and warm weather is front of mind it is good to consider the impact that heat can have on dairy cows.
Furthermore, consumers are increasingly more concerned about animal welfare and environmental impacts of dairy systems. Looking at permanent solutions to these concerns through genetics is just one way we can help to deliver a solution.
With a focus on how we can breed a cow that will be more sustainable and climate-resilient into the future, there are two approaches says Professor Jennie Pryce, “Proactive and reactive: working on genetic selection for reducing greenhouse gas emissions from dairy cattle, this work would be considered pro-active. On the reactive side we have been working on genetic selection of cattle that are more tolerant to heat.”
When it comes to heat tolerance, a cow that is more tolerant to heat has less reduction in dry matter intake and milk yield during a heat event. This is possibly due to her ability to maintain a cooler core body temperature.
The Heat Tolerance ABV allows herd managers to select an animal based on their ability to hold production in hotter and humid conditions. “How heat sensitive a cow is, is highly correlated to milk production traits. This makes breeding the cow-of-the-future a balancing act; between maintaining milk production and ensuring that she will be profitable and healthy in whatever our future climate will look like.” Says Professor Pryce.
Across fertility and heat tolerance the solutions are many and varied, both influenced by the herd managers daily decisions as well as their longer-term genetic decisions. Genomic selection gives us the tools to tackle challenges of our era and the ability to apply new traits to our current dairy herd, with the solution being longer-term, permanent and cumulative.
Visit the DairyBio webpage to find out more about the innovation programs.