Heterosis has a big impact on your productivity – but what does it really mean? It becomes clear when you look at the difference between buying LY gilts or having a self replacement gilt strategy in your production. The benefits of DanBred LY gilts can be seen in more liveborn, less fighting, and better sow longevity.
There are many benefits to be gained from DanBred’s LY or YL gilts. Anders Jensen from Asdal Hovedgaard, Denmark, was employed back when they had self replacement gilts and witnessed the switch when they began buying DanBred LY gilts two and a half years ago. The farm has 1,050 sows and annually produces 60,000 pigs from 7 to 110 kg. They chose to switch because they realised that their production set-up was not equipped to handle self replacement gilts in terms of space and feeding.
More liveborn in just two years
The farm chose to change strategy and buy DanBred LY gilts instead. And it paid off. Anders Jensen explains that, among other things, they have noticed an improvement in the number of liveborn piglets, which is now at 19.5 piglets per litter. This is one to two piglets more per litter than when they had self replacement.
“In addition to getting more liveborn, the purchased gilts are also calmer. And management is better and easier, as we buy exactly the number of animals we need,” explains Anders Jensen.
DanBred LY gilts are known for their calm and docile temper, which makes them well-suited for modern pig farming, as they are gentle and manageable for the farm workers.
Danish Agriculture & Food Council, Breeding & Genetics, has studied the longevity of LY or YL gilts compared to self replacement gilts, where zigzag gilts (LYL/YLY) are produced. Their research shows that heterosis plays an important role in the sow longevity, as LY gilts have an average lifespan that is 50 days longer than zigzag gilts.
When a sow cycle is 150 days, a longer life of 50 days is equivalent to LY gilts getting one third of a litter more than zigzag gilts. That is because LY gilts, which is an F1 cross between Landrace and Yorkshire, achieve 100 % heterosis, while zigzag gilts often have around 60 % heritability.
“The difference between self replacement and buying gilts is worth paying attention to when it comes to sow longevity. The heterosis helps to improve sow survival,” says Martin Mølgaard Pedersen, Head of Department at Breeding & Genetics, and continues: “Anders’ other production advantages are also something we can see in the LY gilts that DanBred and the breeding herds produce.”
Heterosis is defined by the crossbred offspring exceeding the average performance of the purebred parents.
This means that e.g. DanBred D(LY) crossbreds typically perform even better than the average performance of the purebreds DanBred Duroc, DanBred Landrace and DanBred Yorkshire.