Are you overlooking the passive improvement you could gain in your herds’ fertility? In combination with good management practices, a consistent focus on breeding for better fertility plays a critical role in improving your bottom line.
Dairy producers need no reminding of the importance of fertility to the success of their business. They’ve worked hard to improve their herds’ reproductive performance, above all as a means of maintaining efficient milk production and profitability.
But some may still be overlooking the passive improvement they could gain in their herds’ fertility – with little extra effort or cost.
This improvement comes from choosing the right genetics – in particular from choosing their highest fertility females for breeding their replacements, and by breeding these animals to the leading Fertility Index bulls.
This, in turn, will improve their herds’ lifespan, as not being in-calf remains the single biggest reason for culling in UK herds (Kingshay Dairy Manager, 2019).
According to Kingshay, the cost of infertility in the average costed herd is 2.31p per liter (£197 per cow). Looked at another way, extending the calving interval beyond 365 days costs £4.26 per cow per day.
Of course, management plays a critical role in cutting these costs, but the odds can be stacked in your favour if the genetics of fertility are also improved.
Cattle from the Nordic countries are renowned for their health and fertility. While good management plays a part in this trend, it is also assisted by a more passive gain. It is an appreciation of the importance of health and sustainability which has driven the dairy producers of Sweden, Denmark and Finland to breed the most healthy and fertile cattle in the world.
Today, this is seen through the bulls on offer in the VikingGenetics stud, which dominate international listings for health and fertility, in the Holstein, Jersey and the red breeds.
For example, in the last running in the UK, VikingGenetics have two of the top five Holstein bulls ranked on daughter Fertility Index, while the Jerseys and VikingReds fare even better, dominating the rankings on Profitable Lifetime Index (£PLI), the UK’s national breeding goal. In the UK’s international rankings for all available bulls, well over half of the top 20 Jerseys, a staggering seven of the top 10 young genomic Jerseys and an unmatched 100% of the top 10 red breed bulls originate in the VikingGenetics stud.
“Of course, it is not recommended that bulls are selected on daughter fertility alone, but it’s important to look at the genetics of fertility as part of a broader breeding strategy,” says Lars Nielsen, Chief Breeding & Production Officer at VikingGenetics.
“This is arguably more important in some breeds than others, where there is wide variation in Fertility Index, and even some leading £PLI bulls fall down when it comes to transmitting good daughter fertility,” Nielsen adds.
This genetic progress in fertility is seen clearly in the Jersey breed, where the UK’s top 10 £PLI bulls have Fertility Indexes ranging from -7.6 to +16.3.
With each point in UK Fertility Index (FI) representing a 0.6-day improvement [reduction] in calving interval, this means daughters of the lower FI bull would have, on average, a 14.3 day longer calving interval than those of the bull with the highest FI.
“This may not sound much in isolation, but these improvements are permanent and build up over the generations, so can have a significant impact across a herd and over time,” he adds.
Farmers philosophy - key to fertility success
Professor Britt Berglund from the Department of Animal Breeding and Genetics at the Swedish University of Agricultural Sciences attributes the Nordic countries’ successes in health and fertility to the farmers’ mentality as well as the early computerisation of recording and the importance society attaches to these traits.
She says: “We started recording fertility as early as the beginning of the 1970s and had developed a genetic index for fertility which was included in the Nordic Total Merit Index by the mid-1970s. The dairy associations were also very early to computerise all recordings and connected information from a variety of sources, which by the mid-1980s extended to vets and foot trimmers.”
All of this gave the Nordic breeders a head-start on the rest of the world and while other countries were selecting more single-mindedly for milk production, the Viking countries were developing genetic indexes for health and fertility too.
Today, the VikingGenetics countries’ genetic expression of fertility is amongst the most sophisticated in the world. VikingGenetics´ fertility indexes include traits such as days from calving to first insemination, days from first to last insemination, number of inseminations per pregnancy, conception rate and the strength of oestrus expression.
Moreover, Professor Berglund and her team are studying the genetics of dairy cow fertility all of the time, and the current focus includes hormonal changes and pregnancy losses.
Some of the hormonal traits are not only higher than expected for heritability but can also be linked to regions of the genome. So, the promise of new genomic indexes for these fertility traits and others will help keep the genetics from the three Viking countries one step ahead.
She says: “The genetic trends for functional traits in the VikingRed breeds have shown that it’s possible to maintain good fertility and calving performance along with increased milk production. By using this experience and carefully considering the balance of traits in our breeding programmes, this continues to be extended to all of our dairy breeds.”
All genetic indexes used in this article are from April 2020.