MLA Resource Flock
What is the Resource Flock
The MLA Resource Flock first began as the Sheep CRC Information Nucleus Flock (INF) in 2007 and ran for five years until 2012. Over these five years, there was a large number of traits collected every year on the progeny of 5,000 ewes that were joined to over 100 industry sires annually.
From 2012, the MLA Resource Flock commenced and began collecting traits that are hard to measure (phenotypes) and genotypes on the progeny of sires nominated from the industry by breeders.
The 2025 and 2026 matings are being completed under the support of the MLA Donor company as well as support from The University of New England, Western Australian Department of Primary Industries Research and Development and Murdoch University along with a contribution from Sheep Genetics Members.
The design of the Resource Flock has remained similar throughout it’s many incarnations. Briefly, about 1600 lambs are being produced each year from artificially inseminated matings to Merino and crossbred ewes located at 2 research sites at Katanning (Western Australian DPIRD) and Kirby (University of New England).
The lambs are progeny of industry Terminal (The lambs were progeny of industry Terminal (Poll Dorset, Suffolk, Texel, White Suffolk, Southdown, Hampshire and Dorpers), Maternal (Border Leicester, Coopworth, Corriedale, Composites) or Merino (Merino, Poll Merino ranging from superfine to dual purpose types) sires, representing the major production types in the Australian sheep industry. The sires that have been chosen for the project represent a wide spectrum of genetic resources relevant for the future genepool of the Australian Flock. Most have also been selected based on ASBV to represent a wide range across the various traits.
In addition to these sites, add-on projects are run to complement the MLA Resource Flock. These projects aim to capture information from breeder flocks, some of which is not captured in the MLA Resource Flocks such as reproduction. Add-on projects also aim to target how information for hard-to-measure traits can be collected on-farm.
Interesting Facts
- 1,774 Sires progeny tested since 2014
- Sires reflect the diversity of the National flock encompassing Maternal, Terminal, Merino and Shedding breeds
- All Resource Flock sires are genotyped along with their progeny and the research dams.
- Providing a genomic reference for the contributing flocks and the national sheep flock.
Figure 1. Breed contribution to Resource Flock sires for the 2014 to 2025 lamb drops.
Resource Flock Mating Design
The resource flock is focussed on building the genomic reference that underpins the LAMBPLAN and MERINOSELECT evaluations. Consequently, the mating design is balanced around providing high accuracy breeding values for the contributing sires for hard to measure traits and building a genomic reference that describes the diversity of the industry. Consequently, in comparison to traditional progeny tests the resource flock is focussed on maximising the number of sires and will join comparatively less progeny per sire, approx. 16 ewes/sire via AI.
Sire allocation is based on breed type with sires separated into Maternal, Terminal, Merino and Shedding breeds. Sires are used across Dam breed type and Sites to create linkage and avoid confounding.
Figure 2. Simplified representation of mating design for the 2025 Resource Flock mating.
Why Nominate Sires
- Capture hard to measure carcase data on sires of importance – higher accuracy for nominated sires
- Build the genomic reference for your flock – greater accuracy in young, genotyped animals
- Improved bench marking for carcase traits
- Improved selection accuracy and greater genetic gain
- Genetic Linkage across the LAMBPLAN and MERINOSELECT evaluations
2026 Joining sire nominations
Nominations are being accepted by Meat & Livestock Australia (MLA) for the 2026 Resource Flock joining. All breeds are encouraged to nominate as the Resource Flock aims to build a genomic reference population of hard to measure traits. A focus is to sample a diverse range of sires that are reflective of Australia's sheep industry.
The selection criteria will be based on relationship to sires already in the Resource Flock, genetic diversity and index values.
Breeders will not be reimbursed for the cost of semen or semen collection. Despatch and freight costs will be covered by UNE/MLA.
With the delivery of Combined LAMBPLAN the need to capture the MATERNAL breeds continues. A focus of the 2026 matings will again be to capture the diversity of the Maternal Breed population with nominations from these breeds highly favourable.
Key Steps
- Nominations are now open, nominate today (see link to the right)
- Breeders will be advised of successful nominations in late October
- Breeders to organise semen collection by end of November with final shipping early December
Selection criteria of sires for the resource flock
The MLA Resource Flock aims to develop an industry reference population and focuses on diversity more than genetic merit.
Key selection criteria include:
- Relatedness to animals already in the MLA Resource Flock – animals that are less related to the animals already used in the resource flock are preferred.
- The age of animal – is the animal reflective of the industry into the future? Younger animals are more likely to be related to future populations.
- Representation of the breed in the industry.
Annually approximately 115 sires are selected from a range of breeds. The number of sires selected from each breed depends on the:
- representation of these breeds in industry
- size of the reference already created for each breed.
MLA Resource Flock add-on projects have their own selection criteria outlined in the Expressions of Interest of each project.
Project Update - ’25 joining
Spring is an exciting time for the 2025 drop with the Katanning lambs due to be weaned at the end of September with lambing due at Kirby in the next month. The AI mating at both sites has gone as planned with both sites reporting good reproductive rates.
Katanning - conception rate of 81% and a reproductive rate of 1.86 (foetuses per ewe pregnant)
Kirby - conception rate of 71% and a reproductive rate of 1.35 (foetuses per ewe pregnant)
What is measured on the Resource Flock lambs
- Sires are joined to a combination of Merino and First-cross Merino ewes
- Each sire is AI to on average 16 ewes per year across 2 research sites, Kirby (NSW), Kattanning (WA) and Temora (NSW)
- The resource flock is designed around providing a genomic reference for carcase and eating quality traits. Progeny from each sire are recorded for hard to measure carcase traits including;
- Weight traits, scan traits, WEC
- Carcase fat depth, Carcase eye muscle depth, Carcase weight, GR Fat
- IMF, pH decline, ultimate pH, Shear Force
- New technologies i.e. DEXA, MEQ probe IMF
- Methane and Feed Intake via overlay projects
How to get involved?
If you are interested in nominating a sire/s to be used at the MLA Resource Flock sites, nominations open annually in spring. Details of the nominations will be communicated via monthly updates, Breeders Bulletin and email.
If you would like to receive these publications, contact us or subscribe to recieve our monthly e-newsletter. Details of the nominations will also be published on the website
Applications for MLA Resource Flock add-on projects will also be sent through these communication channels.