Sheep genetics take big step with new system

Beef and Lamb New Zealand Genetics has launched a $5 million genetic evaluation system set to revolutionise the sheep breeding industry.

Beef and Lamb Genetics general manager Graham Alder said the new evaluation, named ‘‘single-step’’ was the result of four years of research.

‘‘Single-step provides more accurate estimated breeding values in young animals,’’ Alder said.

‘‘Breeders can work out a ram’s merit at birth rather than waiting for at least two years until the ram has lambs on the ground.

‘‘This, in turn, allows the farmer to better use younger breeding animals in seed-stock breeding programmes [seed stock are animals registered with a breed association], which means faster genetic gain,’’ he said.

The test was done from a blood sample or small piece of tissue from the animal, Alder said. It was often taken from the lamb when it was eartagged just after birth.

Other species were taking advantage of single-step to speed up the genetic gain. It was fast becoming the standard technology for all productive species worldwide.

Steve Miller, director of genetic research at Angus Genetics in the United States, said ‘‘if you’re a breeder doing a lot of genotyping and phenotyping – you’re measuring all of the data in all of the traits – single-step genomic evaluation lets you leverage the accuracy from that immediately’’.

‘‘I think that’s a strong component of why breeders may become even more active in genotyping than they have been so far,’’ Miller told a sheep breeder forum.

Genotype refers to the genetic code contained in almost all living things, which is unique for each individual. Phenotype refers to the observable traits that are apparent from the organism’s genetic blueprint.

The message from Miller that caught sheep breeders’ attention was the accuracy that genomics brings about the influence of grandparents. While parents contribute 50 per cent of an offspring’s genetics, grandparents do not generally contribute 25 per cent as might be expected.

A quarter is an average, but genomics reveals the actual contribution of grandparents can be much higher or much lower than 25 per cent, providing a powerful insight and tool for breeders.

Miller emphasised the ease that single step brings to breeding as evaluations were always current because they collated all available information in real time.

The introduction of single-step was part of a bigger picture which will provide sheep farmers with direct access to the national flock’s genetic evaluation.

‘‘Single-step provides more accurate estimated breeding values in young animals.’’

Graham Alder