Beefing up the dairy industry
The dairy industry is a wonderland for geneticists. The quality and quantity of animal recording is unmatched by any other industry. Few dairy farmers can get by without using artificial insemination and this means that sires end up with progeny spread over many farms around the world. At the time of writing the highest ranking Friesian sire in NZ (Carson’s Mecca Pulse S1F) has 2,052 performance recorded daughters spread across 864 herds. The reliability of his breeding worth (BW) index value is 98%.
Performance recording is a normal part of dairy management, 66% of NZ’s 4.7 million dairy cows are tested for milk production each year and almost every calving is recorded (although with varying levels of diligence).
When you have data this good, you can put a lot of trust in it. And that is just what dairy farmers do. The sale value of dairy stock is heavily weighted on their breeding worth score. Most farmers do not study sire lists to choose their bulls. Instead they subscribe to a “bull of the day” type service where the genetics companies ship out semen from a team of the top BW bulls each day. It’s a pretty slick system that generates high genetic merit dairy heifers. It also churns out about 60% of NZ’s beef animals. About 75% of calves born on dairy farms are surplus to requirements and are directed to a meat production system of some kind. In addition, eventually, nearly all the others end up embarking on an OE as mincemeat later on. Herein lies the challenge of beef, how can we improve the growth, carcase quality and farm-a-bility of beef in NZ when much of it is a by-product of the dairy industry?
There are the hoarse battle cries of those that have spent years trying to “educate” dairy farmers into using “better” beef sires. I don’t blame dairy farmers for being budget conscious on their bull power. They need to buy a lot of bulls each year (following best practise, the average farm would buy about 12-15 bulls for follow up mating alone) and they reap no benefits from “fancy” bulls offering traits such as superior growth rates or carcase traits. Unless they are finishing the calves themselves, dairy farmers usually only care about 3 traits in their beef bulls. Calving ease (i.e. less sick dairy cows), gestation length (i.e. early calving means more days in milk) and well-marked progeny (i.e. any sleep deprived fool can tell that the calf is not for milking).
Compared to dairy bull breeding values, beef bull breeding values have much lower reliability (about 40-50%) because pedigree and performance recording is far patchier in the beef industry. Breeding values are also difficult to compare across beef breeds. I think we can forgive dairy farmers for not investing top dollar in high-index beef bulls when they are accustomed to viewing reliabilities of nearly 100% and, at the end of the day, all they really want is a safe calving for their cows.
So, have we been looking at this problem the wrong way? Instead, can we harness the great recording machine that is the dairy industry to improve the genetic predictions of our beef stock? This is already being done on a small scale with the DairyBeef progeny test run by Beef +Lamb NZ Genetics and Wagyu contract mating run by Firstlight and I think it has great promise.
Imagine a world where the top NZ beef sires have 4000 recorded offspring? Actually, even 100 recorded offspring would be sufficient to give high accuracy breeding values for most traits. That is possible within the realm of dairy. Most of the recording infrastructure is already there, the cows are waiting to be mated, and the people that own them don’t even really care which sire you use so long as you meet a few small demands. All the progeny are even wearing EID tags. We just need some enterprising souls to fill in the gaps!