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Affordable tool takes costly guess work out of ET heifer selection and highlights bulls that may have otherwise been over looked
The use of genetic marker profiles is accelerating the rate of genetic gain for Dutch dairy producers using embryo transfer.
Hans Hurkmans runs an embryo transfer (ET) company that services 60 herds in The Netherlands and offers IGENITY®, Merial's genetic profiling tool, to clients who are unsure of which heifers to flush, based on pedigree information alone.
"Using genetic marker profiles provides them with 'inside information'," says Hans. "It gives them solid data about an animal's genetic potential that helps them decide exactly which heifers to flush, and which to AI or to sell. There's none of the guess work or chance that's associated with selecting heifers for ET work based on pedigrees alone."
Hans first introduced the technology to his customers 18 months ago and so far up take has been extremely good. More than half of his clients have begun to use IGENITY, which costs around �40 per animal. "And all have been very impressed and have continued to use it since. For them, there's been no going back once they see what selection based on genetic marker profiles can do."
Profiling is certainly helping to speed up the rate of genetic progress for these Dutch breeders. Some resultant heifer calves have also been tested at 10 months old and the 'best' have been flushed two or three times before being artificially inseminated and then calving at 24 months old. "You can't get much faster than that. And it's all being done with the knowledge that the animals are genetically superior to their herd mates. We're working with definitive information — not likelihoods and probabilities. The data is real and it's current — not historical," says Hans, who is very excited about the technology offered by IGENITY.
He says that he and his clients still initially select heifers for possible ET work by pedigree and then 'narrow' their selection down using IGENITY. He says it would be difficult to sell stock or embryos without an impressive pedigree using marker profiles alone at the moment as not enough people are aware of the technology and how it works.
"But I believe that in future many producers will look to genetic profiles, rather than pedigrees, to assess stock before they buy or sell. And why wouldn't they? Genetic data is fixed — it can't be altered. You can't get more reliable than that."
The Jersey Cattle Society is looking to exploit that reliability in a bid to tap into genetic potential within the breed that would otherwise have been over looked.
Since many Jersey producers keep a young Jersey bull on farm for use on maiden heifers, less than 5% ever gain a proof. "They don't have the opportunity to produce enough daughters and, as a result, the breed is losing a lot of vital breeding information," says the society's Roger Trewhella. "But using IGENITY could help to identify bulls that would otherwise be hidden away on farms and it will help to prevent that loss of data and genetic potential.
"Genetic marker profiling will allow us to tap into Jersey genes that may otherwise have been over looked," he adds.
"And it could also help us to prevent the scenario where a producer has a dozen or so excellent daughters by a bull in his herd and by the time they have a production proof the bull is dead — that's also very frustrating."
So, the Jersey Cattle Society has a plan — to get all of its members to test their breeding animals. "It's like a jigsaw. We have to get all the info — or pieces of the puzzle — before we can complete the bigger picture," says Roger. "And IGENITY will allow us to ensure that we have the correct — and very best — genetics to build a strong future for our breed."
Press Release
A new chapter in UK dairy cattle breeding allows changes in genes to be analysed to define an animal's true potential through only a few strands of hair plucked from the animal's tail switch.
Gene markers which influence traits like milk yield, butterfat and protein levels are set to become a main stream breeding tool among Britain's dairy farmers.
Extensively used in other livestock producing countries, including the US, France and New Zealand, Merial Animal Health's IGENITY testing service brought gene markers, which identify specific genetic traits in dairy and beef cattle, to the UK.
Merial has combined a number of gene markers into one simple test which enables the breeder to measure production parameters through the DNA extracted from the hair follicles in the laboratory.
IGENITY'S head in Europe, Nigel Otter said: "If you identify the current genotype profile of your dairy herd, changing that profile can quickly pay off. Gene markers are set to become a main stream breeding tool in the UK for both pedigree and commercial producers. They are being used extensively in other countries."
The English Guernsey Cattle Society is already investigating the genetics behind the protein found uniquely in the majority of its cows which is believed could provide better protection against autism in children, schizophrenia, diabetes and heart disease.
Society field officer Digby Gribble said: "Guernsey milk samples have tested as more than 90 per cent Beta Casein A2 which is the desired type of Casein but there are bloodlines within the breed that carry the A1 Casein.
"The case for A2 is still being investigated but each new study does reinforce the argument for its benefits. We have a unique opportunity to become the only significant dairy breed to have majority A2 status."
The society collects semen from 10 young bulls annually and it is working with IGENITY to test these for the Casein A2 gene.
Gene markers will become increasingly important as another breeding tool, believes Jersey Cattle Society field services manager Roger Trewhella.
"We carried out IGENITY tests on a random sample of 40 cows and they came back with quite a diverse picture. I would have expected the tests to conform with the traits of the breed — relatively lower yields than black and white cows and higher butterfats — but the results proved much more useful.
"The range of results has been more distinctive than in other breeds which is good in terms of looking at how we move forward.
"Butterfat is very important as far as the Jersey breed is concerned but in some markets it is not necessarily the highest butterfats which are needed. Gene markers give a wider picture and could be incorporated into bulls proofs."
Merial's first test identified a form of leptin, an appetite-regulating protein that an animal produces.
Now this test has been further developed to look at a number of other gene markers which are indicative of the dairy cow's body condition, fertility and longevity.
The development of the next generation test, marks both condition score in the post-calving period and the pregnancy rates to first service.
Leptin concentrations are elevated during late pregnancy and decline to a low point at calving. Recent research shows that cows with a higher overall positive energy balance have significantly higher leptin concentrations than cows with overall negative energy balance.
This suggests that leptin concentration is a sensitive indicator of energy balance in cows in early lactation.
"Producers have been breeding high performance cows which milk well but in some cases can lose fertility and the test identifies cows that are better able to hold body condition score," said Mr Otter.
"Breeders can select for gene markers in the high yielding cow which enable her to keep up her dry matter intake and maintain her body condition. There is also a direct correlation between a cow's body condition score, metabolic, foot and leg and fertility disorders," he added.
Other profiles developed so far show the genetic potential for milk and butterfat yield and protein content.
The tests identify animals which either produce high volumes of milk or high constituent values of butterfat and protein — two different types of dairy cow.
These markers are licensed from New Zealand farmer-owned specialist dairy genetics and AI company Livestock Improvement Corporation's GeneMark, the largest commercial bovine DNA analysis service in the country.
LIC's UK general manager Robert Hassall said gene markers provided a quicker and more accurate way forward for breeding programmes.
"We are still going to have to produce bull proofs but the gene technology will accurately predict which will have production traits.
"You could breed the top bull with the top cow and its calf could be the biggest dud. It's a long process to get to the proof of the progeny.
"Initially, for UK producers I would see the biggest use of gene markers in selecting stock for the milk market you are supplying — if a producer has a batch of 50 heifers and wants to sell half of them, he can test for production of solids or liquid depending on the type of milk contract he has."
IGENITY is also geared at milk producers who are selling for cheese processing, identifying kappa casein, beta casein and beta lacto globulin which influence not only cheese yield but renneting time and coagulation.
For the future, Merial is aiming to increase its range of products to include gene markers for mastitis resistance and other important cattle diseases.
For further information about the IGENITY Profiling service please call 0845 603 8895
or alternatively email igenity@cscuk.co.uk.
To order an IGENITY Profiling kit, please click here
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