Findings showed that animals with a superior immune competence phenotype had significantly lower health related costs and mortality rates.
Angus Australia and the CSIRO partnered over a number of years to undertake research into genetic traits related to immune competence and resilience.
In a world first for the beef cattle industry, the research undertaken by Angus Australia and CSIRO has resulted in the development of the breeding index value, ImmuneDEX.
Announced at the Angus through the Ages National Conference, ImmuneDEX is a genetic description of an animal’s ability to react to an immune system challenge (i.e. disease).
Over the course of a number of years, Angus Australia and CSIRO have worked in collaboration to immune competence test calves from the Angus Sire Benchmarking Program (ASBP), with the research co-funded by the Australian Lot Feeders Association via Meat and Livestock Australia.
To develop the ImmuneDEX breeding value, immune competence phenotypes were collected on approximately 3000 Angus steers and heifers at weaning and analysed. This information, combined with genotypes (DNA Profiles) was analysed to determine genetic parameter estimates (heritability’s and correlations) and to produce Research Breeding Values for immune competence.
Christian Duff, Angus Australia Strategic Projects Manager, said that the work done to develop the ImmuneDEX breeding value was a successful collaborative effort between those at CSIRO and Angus Australia.
“It is has been excellent working in collaboration with CSIRO on this research,” Mr Duff said. “While there is still more research to be undertaken to further develop the ImmuneDEX breeding value and validate its potential to deliver health benefits to industry, this development is a definite stride for Angus breeders and the broader beef industry.”
Furthermore, on a subset of 900 steers from this study, disease incidence during feedlot feeding was examined.
Findings showed that animals with a superior immune competence phenotype had significantly lower health related costs and mortality rates.
Importantly, the genetic strategy is expected to assist in reducing the use of antibiotics, improving overall welfare and health of the animal, and maintaining consumer confidence.
While still in its early research stages, the information now available through the ImmuneDEX breeding value will assist beef producers make decisions about what the best animals are to breed from into the future with the goal of improving animal health while simultaneously improving productivity.
Dr Brad Hine, Research Scientist at CSIRO explained the perspective long term benefits of the ImmuneDEX research findings.
“We know if we continue breeding with a sole focus on production a consequence we will inadvertently increase susceptibility to disease and associated antibiotic use.”
“We envisage that ImmuneDEX will provide a long-term strategy to help address this problem by allowing the producer to put selection emphasis on the immune competence of animals and put that into our selection thinking to breed animals that are both productive and have a better ability to resist disease challenges.”
The ImmuneDEX value is moderately heritable and weakly negatively correlated with some production traits (eg carcase weight) while being weakly favourably correlated with stress-coping ability and temperament related traits.