J Newton1, J Pryce1,2
1Agriculture Victoria, AgriBio, Centre for Agricultural Biosciences; 2School of Applied Systems Biology, La Trobe University
ImProving Herds, an Australian dairy industry project, was initiated to accelerate genetic gain and increase usage of herd improvement tools through simple, data-driven decisions that deliver profits to farmers.
Twenty-seven farms provided economic and production data and the project provided genotypes on each farm’s heifers. Ten years of data (2007–2016) was used to compare the performance of herd contemporaries of differing genetic merit. Each cow’s margin over feed and herd costs (MOFH) was calculated by summing income from milk, calf sales and final salvage value and subtracting cost of rearing, feed and maintenance; costs associated with mating and mastitis events.
On average, the top 25% of cows (ranked on Balanced Performance Index, BPI; Australia’s dairy selection index) had a $300/cow/year greater MOFH than the bottom 25%. The top 25% of cows produced 88kg/cow/year more milk solids and lasted, on average, eight months longer in the milking herd. Additional milk income easily compensated for higher feed costs of high BPI cows.
Pre-calving genomic estimated breeding values (GEBV) were compared with first lactation production records corrected for fixed effects for each farm. The realised reliabilities between GEBV and corresponding production records ranged between 0.66 and 0.77 for milk, fat and protein yields, similar to published national mean reliabilities for equivalent traits. These results provide independent evidence of the accuracy of GEBVs in Australia
The ImProving Herds project is creating change in industry; 86% of survey respondents said their thinking about genetics had changed after seeing project results at industry events. Many of the farms involved have also become advocates of genetics, facilitating future farmer-to-farmer learning. A suite of legacy resources, new tool development, and a commitment to continue extending results to industry, means Australia’s dairy farms will reap the benefits of genetic improvement well into the future.
Dr Jo Newton works as a Research Scientist in Genetics for Agriculture Victoria. As a 2018 Endeavour Post-Doctoral Fellowship Recipient she spent 6 months as a visiting scientist at Teagasc, Moorepark in Ireland. Jo is passionate about undertaking research in animal breeding and genetics which delivers tangible benefits to industry. She is an advocate for young people working and studying in agriculture and champions agriculture as a diverse and rewarding career choice. Jo holds a PhD in quantitative genetics from the University of New England.