DNA set to boost bull breeding goals

Performance recording has had a big influence on the development of the Tomschoice Limousin herd owned by James and Sarah Cooper. But new developments on the horizon will have an even greater part to play in identifying superior traits for the benefit of both pedigree and commercial breeders.


The herd, at Dacre, Harrogate, North Yorkshire, was established in 1996 and based on carefully selected foundation females that have produced five principal cow families. “Performance recording was introduced within two years of the herd being set up, primarily to give us the information we needed rather than just to help us sell bulls,” says James Cooper.


“Our bulls are gaining an average of 1.5-1.6kg a day during their first year, with heifers at 1.1kg. Because these figures give commercial buyers more confidence about a bull’s potential, they’re now taking recording into consideration more readily. But it’s the next step breeders can take in trait evaluation that will make the job even more efficient for commercial bull buyers.”


He’s referring to DNA testing, which the Coopers consider will have a big impact on how pedigree breeders select for superior traits, and which will inevitably bring big advantages to the commercial cattle sector.


“DNA will take selection for superior traits to a new level. We will embrace it wholehertaetedly and believe it will significantly increase the level of predictability in terms of performance. Our first samples will be sent to Igenity for testing this year and I’m sure we’ll soon see some real benefits.


“We’ll continue to weigh and record as we do now, but I think the EBV will change to a combination of DNA and weight recording. We also scan at about 400 days; it gives us another insight into a bull’s performance in terms of muscle development, rather than letting us assume a bull is performing well when it’s only putting on fat.”


Limousin-group


DNA testing will help identify the star performers in the next generation of the Tomschoice herd and ensure cattle carrying superior traits are identified early on


But Mr Cooper does have concerns about the current performance recording system: “I don’t think it’s right that cattle that aren’t scanned can still have figures relating to muscle depth added to the EBV calculation at sale time.


“All our bulls are scanned. To give a fair assessment a herd should scan all its bulls and not just a proportion. This means some of the information given to commercial bull buyers isn’t true and that’s not good for the breed. It introduces an unnecessary distortion through non-proven figures. It should be no scan, no figure.”


High weight gain isn’t everything, he says. “We have some bulls averaging 2kg a day, but it’s really too much. They are growing faster than their skeletal frame, ligaments and tendons can cope with, so high weight gain mustn’t be regarded as the be-all and end-all in terms of a sire’s superiority.”


Although devotees of performance recording, the Coopers are adamant bulls must be allowed to grow naturally and not “pushed” simply to achieve high weights, which can often lead to problems when bulls are expected to work in commercial conditions.


Management of the Tomschoice herd is geared to natural growth with great emphasis placed on legs, locomotion and temperament. Bulls are housed in spacious and airy straw yards during winter, but soon after Christmas are turned out for a few hours every day. By April they are grazing for about seven hours a day.


Bull calves – born January to March – have early access to an 18% protein creep feed. The diet is changed to a 15% protein mix at weaning in October. Calves are weighed at 100 days and 200 days. A typical 200-day weight is about 350kg with heifers at 300kg.


“At this stage they settle to gain about 1.4-1.5kg a day, but because they are running outside, they gain muscle and not fat. Calves aren’t fed any creep when outside, but eat plenty when they come in at night.”


Weaned calves are also fed “wetted” sugar beet shreds twice a day when housed – as well as their ad-lib ration – and also have access to hay and straw. Starch and protein levels of the ration are “tweaked” as necessary during winter.


The target 400-day weight for bulls is 650kg, although some reach more than 750kg. “We have some cows with EBV’s of 30 and over and they always throw the fastest-growing calves, although we have to be careful these bulls don’t over-achieve in terms of weight gain and put undue pressure on their developing skeletal frame.”



  • For coverage of last weekend’s Limousin sale at Carlisle click here.