Top and average difference worth plenty
THE difference between a Simmental bull in the top 1% and top 25% is 0.1kg/day higher liveweight gain and 63 fewer days to slaughter, according to a study at Denston Hall Farm.
In the research, conducted by Genus, progeny from three of the farms stock bulls were compared with progeny from AI sires, said Neil Wharton, the companys beef specialist. "Bulls from the farm are in the top 25% of the Simmental breed and AI bulls, the top 1%. On many farms, bulls used will be of poorer quality than on this farm."
Cattle on the trial were fed 1kg concentrate a head a day and grass or silage until slaughter. "Progeny from stock bulls grew at 0.69kg a day and that from AI sires, 0.79kg a day. Stock bulls progeny finished at 500 days, whereas AI bulls progeny reached the same weight 63 days sooner. Assuming a feed cost of 70p a day, this brings a saving of £44 a head."
With bulls averaging four working seasons, siring 40 calves a year, this would equate to £7040 over the bulls lifetime, said Mr Wharton.
High bull prices seen at Perth last month make being aware of sire costs imperative, he added. "Calves from a £2500 bull, readily available two years ago would have sire costs of £28 a calf." But last month, similar bulls were easily making £4000, raising the cost of a calf to £38, assuming a bull sired 160 calves in his life.
"Not all bulls sold are of the highest quality and paying serious money for a bull does not guarantee he is a good one," warned Mr Wharton. "As a company, we do not look at bulls unless they are performance recorded. And then we only look in the top 10%." *
Differences in progeny performance between top and average bulls can be worth thousands of £s, says Genus