Genomic Opportunities for Commercial Angus Breeders

Matt Reynolds, Breed Development Officer

Opportunities are available to incorporate genomic based tools in commercial herds for the selection of Angus heifers and steers. This was the focus of a session in the Autumn 2021 Angus CONNECT Research and Development event.

“Genomics, in relation to livestock production, is an advanced field of science that essentially interrogates an animal’s DNA profile. DNA being the genetic instructions for the development and functioning of all known organisms.” said Angus Australia’s, Strategic Projects Manager, Christian Duff. “Genomic technology, coupled with a highly effective reference population, and modern analytical models, a prediction of a commercial Angus animal’s genetic makeup, for important beef production traits, based on a simple DNA sample, is possible and available now for Angus heifers.” Mr Duff added. The highly effective reference population, linking phenotypes with genotypes, stems from Angus Australia member data, coupled with a suite of hard-to-measure traits (e.g. direct carcase, feed efficiency, immune competence) recorded in the Angus Sire Benchmarking Program. This is crucially formed from Australian Angus cattle run in Australia production systems. Genomic based selection is available for Angus heifers through the Angus HeiferSELECT product where genetic predictions are available for nine commercially relevant traits, along with a total breeding index and an associated star rating. The next generation of genomic tools for commercial Angus producers has been the focus of collaborative R&D over the past 12months with the CSIRO, being Australia’s national science agency. “As part of ongoing development and innovation, the Angus HeiferSELECT product will see the expansion from 9 to 13 traits, including genomic based predictions for two feedlot traits, being average daily gain and feed intake, and the disease resilience traits ImmuneDEX. Additionally, the carcase traits will see the transition from intramuscular fat to MSA marbling score and the inclusion of ossification.” Mr Duff highlighted An updated total breeding value has also been developed for the Angus HeiferSELECT product in collaboration with AbacusBio, who have global experience in developing selection indexes for a multitude of livestock species. “Angus SteerSELECT will present a new opportunity for Angus commercial producers. It is based on the same genomic based system to HeiferSELECT, and will include the 9 steer relevant traits covering growth, feed efficiency and gain, carcase attributes and disease resilience”. Said Mr Duff. “Importantly, Angus SteerSELECT in undergoing a thorough validation process, with initial work showing it to be an effective selection tool to draft steers for traits such as marbling and carcase weight particularly in mid-fed and long-fed feedlot production systems.” Mr Duff added. The next generation of Angus HeiferSELECT and the availability of Angus SteerSELECT has a target release for July 2021. Mr Duff finished the Angus CONNECT session on what the future holds “Angus Australia plans, with CSIRO, to regularly update the genomic predictions that underpin both the Angus HeiferSELECT and SteerSELECT products. This will ensure the large but growing and most contemporary Australian Angus reference population data is utilised.” “Additionally, as a feedback loop for Angus SteerSELECT, a model to include effective commercial data from the feedlot or abattoir into the Australian Angus reference population is also being explored with our colleagues at CSIRO.” Further information on the genomic opportunities for commercial Angus breeders is available from the Angus Australia website, or by contacting staff at Angus Australia.

Angus HeiferSELECT Angus SteerSELECT

Trait Group Trait Current New Cow-Calf/ On-farm Calving Ease Direct Yes Yes No Weaning Weight Yes Yes No Milk Yes Yes No Yearling Weight Yes Yes Yes Mature Cow Weight Yes Yes No Feedlot Average Daily Gain No Yes Yes Feed Intake No Yes Yes Carcase Carcase Weight Yes Yes Yes Eye Muscle Area Yes Yes Yes Rib Fat Yes Yes Yes IMF or MSA Marbling* Yes Yes Yes Ossification No Yes Yes Resilience ImmuneDEX No Yes Yes * Intramuscular (IMF) fat transitioned to MSA marbling score in next generation products Figure 1 – Angus HeiferSELECT will see the next generation product expand to 13 traits, while Angus SteerSELECT will be realised with 9 steer relevant traits.