April 25th marks ‘World DNA Day’, a celebration of the groundbreaking discovery in 1953 when James Watson, Francis Crick, Maurice Wilkins, Rosalind Franklin, and their colleagues published papers in the journal Nature, revealing the structure of DNA. In tribute to this landmark event, we explore how genetics are transforming livestock farming, going far beyond pedigree data to improve animal health and productivity, while also reducing carbon footprints on farms.
The application of advances in genetics to livestock farming is moving well beyond pedigree information and being implemented to enhance health and productivity of animals, and even reduce a farm’s carbon footprint.
Increasingly, we are looking for improvement in areas other than the main productivity traits e.g., growth, milk, reproduction, eggs, to target costs to the system, not just outputs.
Traditionally, assessing livestock health relied on subjective observations, leaving room to miss some cases of disease and undesirable genes in carrier animals where the effect of the gene is masked. Genetic testing, however, offers a proactive approach to addressing these issues. It enables detection of genetic markers associated with diseases or deleterious genes, targeted interventions and selection for desirable characteristics, allowing farmers to make precise and informed decisions about their livestock and be proactive about herd health and productivity.
There are many debilitating animal diseases that can be silently carried in a population, for instance inherited microphthalmia in Texel sheep. The parents can look the picture of health but if both carry the recessive gene for microphthalmia, lambs will be born blind. However, this disease can now be eliminated in live sheep using simple commercially available gene testing kits and selective breeding.
Taking this one step further, our partners at the Roslin Institute not only identified a gene delivering resistance to swine flu in pigs, and are now exploring gene editing to reduce both the risk and the impact of a repeat performance of the swine flu pandemic we saw in 2009.
Genetics can impact wellness of animal in other ways. In the dairy industry, high heat and high humidity produces an uncomfortable environment for dairy cows and can lead to reduced fertility and milk production. The ‘SLICK’ gene mutation discovered in 2014 gives the animals a sleek hair coat and increased capacity for sweating and better thermoregulation. This gene is now being integrated into cattle breeding programmes worldwide.
There are also opportunities to use genetics to reduce negative environmental impacts. The Breeding for CH4ange project looks at reducing the carbon footprint of sheep farms using a combination of genetic improvement tools and methane monitoring equipment to breed sheep that produce less methane. It is hoped that this will be extended to other sheep flocks using DNA markers associated with low methane production.
Incorporating advances in genetics into livestock farming not only enhances animal health and productivity but also holds the potential to mitigate environmental impacts. Through targeted innovative approaches like gene editing, farmers can proactively address disease risks, improve animal welfare, and contribute to sustainable agricultural practices.