Merino rams at Hamilton’s Sheepvention.

INCREASED genetic selection for fleece, carcase and reproductive traits in Merinos has driven the Sheep Genetics program to a new milestone.

The latest MERINOSELECT analysis has reached 500,000 genotypes, making it the largest genomic evaluation of its type in the world.

MERINOSELECT is Australia’s genetic evaluation system for Merino producers. It produces Australian Sheep Breeding Values that enable sheep producers to select animals accurately on their genetic merit to suit individual production systems and breeding goals.

Genotyping is the process of finding differences in the genetic makeup of individual sheep in their DNA sequences.

MLA’s manager of Sheep Genetics Peta Bradley  said ASBVs describe the genetic merit of an animal that will be passed on to its progeny.

“ASBVs are the most accurate selection tool available to make genetic progress.

“This importance is heightened when traits are difficult to see visually or can only be observed later in life or in a single sex.”

Meat & Livestock Australia said with 500,000 genotypes reached, this means that the unique genetic makeup of half a million sheep is now routinely incorporated into the industry genetic evaluations on a fortnightly basis.

The increase in number of genotypes, rate of genetic progress and number of animals submitted to Sheep Genetics means that sheep producers have access to more animals with ASBVs than ever before and the merit of these animals is continuing to improve, MLA said.

Ms Bradley said the benefits of having more genotypes in the system will help sheep producers select for traits that can be harder to record on farm or are recorded later in life. Often these traits are still important to on-farm production and include traits like reproduction and adult fleece traits.

“More than 50 percent of the rams for sale this year with MERINOSELECT ASBVs have a genotype that is used in the evaluation,” Ms Bradley said.

“As the use of Australian Sheep Breeding Values (ASBVs) continues to grow within the commercial sector we’ve seen corresponding growth in the number of animals and clients involved in Sheep Genetics.”

Eating quality traits added to fleece, carcase and reproduction selection

Ms Bradley said MLA’s recent Genetics insights survey noted that the use of Sheep Genetics ASBVs by commercial sheep producers increased between 2016–2023 from 14pc to 55pc of commercial producers using ASBVs in their selection.

Using the latest data from Sheep Genetics and the MLA and AWI Sheep Producer Intentions survey, it is estimated that between 50-55pc of all Merino rams sold this year in Australia will have ASBVs reported, she said.

“The influence of animals within MERINOSELECT is expected to be higher when accounting for multiplier flocks and the use of semen from MERINOSELECT sires.

“This increase in the adoption of ASBVs by Merino ram buyers has been reflected in the number of animals submitted into MERINOSELECT,” Ms Bradley said.

“Between 2016 and 2024 there has been a 110pc increase in the number of billable animals submitted to Sheep Genetics for analysis.”

Ms Bradley said genetic progress has been strong in many production traits including clean fleece weight (CFW) and weight (WT) traits.

“Improved pedigree and genomic information has seen more MERINOSELECT producers begin to accurately record and select for reproduction traits including conception (CON), litter size (LS) and ewe rearing ability (ERA).

“Selection on these component traits has seen a 133pc increase in the Weaning Rate (WR) ASBV in the period between 2016 and 2023,” she said.

“This has also been improvement for health and welfare traits like early breech wrinkle (EBWR) and worm egg count (WEC).”

Ms Bradley said there has been analysis wide improvement for intramuscular fat (IMF) and shear force (SF5) in the Terminal LAMBPLAN evaluation.

“And we are beginning to see a number of producers within MERINOSELECT look at these traits as part of their selection.

“The Merino Lamb (ML) index, one of the new MERINOSELECT indexes launched earlier in 2024, is the first Sheep Genetics Merino index to incorporate these eating quality traits along with other important Merino system production traits.”

The MERINOSELECT evaluation is delivered through Sheep Genetics and is supported by the Animal Genetics and Breeding Unit based at the University of New England in Armidale, NSW.

AGBU play a pivotal role in running the genetic evaluation for Merino sheep. All of the 500,000 genotypes are, combined every fortnight with data on 4.1 million animals to produce the genetic evaluation.

“There are over 80 traits and indexes reported from the analysis enabling sheep producers to access tools that help them drive genetic progress towards their breeding objective.,” Ms Bradley said.

“It is a monumental effort by the team to ensure this valuable industry service continues to be a world leading genetic evaluation lead by the Research and Development at AGBU and delivered to industry by Sheep Genetics.”