Reducing the Environmental Footprint of Livestock Through Genomic Selection

Rapid growth of the global population has resulted in rising demand for animal products. In addition to meeting the world’s growing demand for animal protein, producers should respond to the call to become more environmentally sustainable. Selection for livestock that have smaller carbon and nitrogen footprints can reduce feed waste, farm costs, and the use of natural resources at the farm level. Livestock production, especially enteric methane produced by ruminants, contributes to almost 15% of global anthropogenic greenhouse gas emissions. Breeding livestock for reduced methane emissions is difficult and expensive because direct measurement of methane emission requires sophisticated equipment. Alternatively, methane emission can be measured indirectly with affordable techniques, or other traits can be used as a predictor for methane emission. For example, studies have shown that improved feed efficiency and reduced methane production are tightly linked through similar biological processes. Therefore, reduction in methane emission could be genetically achieved by selecting indirectly for more feed-efficient animals. Although environmental management practices are frequently used to mitigate the environmental footprints in livestock, genetic selection for reducing the environmental footprint using indirect methane measurements or a predictor trait such as feed efficiency is a practical long-term solution to respond to the increasing demand for animal products while considering climate change.

Over the past two decades, genomic selection has been demonstrated to be a promising tool for improving economically important traits, especially those that are difficult or costly to measure, such as feed efficiency and methane and nitrogen emissions. The economic, ecological, and social importance of traits associated with the environmental footprint of livestock are well recognized. Global efforts to reduce the environmental footprint of livestock production have been initiated. However, challenges remain for improving feed efficiency and reducing methane and nitrogen emissions in livestock programs through selective breeding. Improvement of those novel traits must also consider production, health, and fertility traits. The goal of this Research Topic is to collect and share the latest research papers from the global animal breeding community about traits that affect the environmental footprint of livestock and poultry production, specifically underlying biology, novel methods for measuring phenotypes and calculating genetic evaluations, and design of breeding programs.

We welcome the submission of Original Research, Methodology, and Review articles on topics related to livestock feed efficiency, methane and nitrogen emissions, and the overall environmental footprint of farm animals within the following themes:
• Strategies to implement genomic selection for optimal genetic gain.
• Design of reference populations to enhance response to selection for feed efficiency or methane and nitrogen emissions.
• Genome-wide association studies to identify genomic regions, candidate genes, and biological pathways associated with feed efficiency or methane and nitrogen emissions.
• Potential genomic selection models using predictor or indicator traits to reduce the environmental impact of livestock.
• Evaluation of the economic benefits from incorporating feed efficiency or methane and nitrogen emissions in breeding programs.
• Understanding of the biology of host-microbiome interactions and use of gut microbiome profiles for selective breeding or improved accuracy of genomic predictions for methane emission.

Topic Editor Dr. Mohammad Ali Nilforooshan is affiliated with Livestock Improvement Corporation (LLC) company in New Zealand. All other Topic Editors declare no competing interests with regard to the Research Topic subject.