Performance recording and genotyping reap benefits
Currently into its second year, a research project has proven that assigning performance records, parentage through DNA, and potentially genomic information to commercial sheep operations could add value to breeding programmes.
AbacusBio consultant Bruno Santos has been working on a study that compares different genotyping strategies and selection options on their economic effectiveness in large-scale commercial sheep breeding operations in New Zealand and Australia.
The project is a collaboration between AbacusBio, Beef + Lamb New Zealand Genetics, the Cooperative Research Centre for Sheep Industry Innovation, and the University of New England, both in Australia.
The higher profitability can be achieved from repeated trait records, DNA parentage, and genomic selection (GS) in the multiplier flock and, in some cases the commercial flock of multi-tier breeding schemes. However, genomic selection must be carefully planned, as genotyping costs are still prohibitive for strictly commercial operations.
“GS tends to be more expensive, and the benefits are relatively modest due to the low selection intensity in producing males for the commercial tier, unless the breeding scheme captures all the value through slaughter lambs or wool production,” Bruno explains.
Selecting multiplier replacements through genomic selection, including those from the commercial flock, can also result in higher profitability. The high selection intensity applied through a two-stage selection process in the large commercial population allows selection of ewes with the very best genetic merit, Bruno adds.
Overall, benefits of recording and genotyping were found in open multiplier scenarios in which replacement ewes are screened in from the commercial tier. The study also investigates the benefits of recording and genotyping efforts when genotype by environment interactions were assumed between the nucleus and commercial environment.
Our research has shown that there is scope to increase productivity and profitability by expanding on performance recording and introducing DNA testing in specific parts of the breeding programme. Nevertheless, careful planning must be applied to counter-balance the large initial investment in genotyping.