A research group led by Jack Dekkers, distinguished professor in the Department of Animal Science at Iowa State University, has received a grant from the National Institute of Food and Agriculture to further genetic improvement of livestock by integrating biological models of growth that have been developed by animal nutritionists.
The $500,000, two-year grant for Dekkers and his team will support the project, "Integration of Biological Models in Genomic Evaluation: Pig-Growth-Model Whole Genome Prediction (PGM-WGP)," as part of a national USDA initiative for Research in Tools and Resources for Animal Breeding, Genetics and Genomics Research.
Genomic evaluation and selection are used to improve the rate of genetic gain by identifying the animals with the best genetics for traits of economic importance. Using these animals for breeding future generations results in a more profitable final product, increased value of by-products and more. However, existing genomic evaluation models often fail to predict how the progeny of an animal will perform when they are exposed to diverse environmental conditions.
This research will take an existing genomic model and integrate it with models of growth that have been developed and used to formulate diets for pigs. This will allow breeders to better predict the genetics of an animal that underpin an animal's ability to grow under different environmental conditions, including temperature, humidity, diets and disease.
"The idea to incorporate a biological growth model into genomic evaluation of pigs is based on similar work that has been conducted by scientists at Corteva, formerly Pioneer, who have successfully integrated crop-growth models into genomic evaluation to predict the performance of corn hybrids under normal versus drought conditions," says Dekkers.
Co-director Nick Serão, assistant professor of animal breeding, agrees, "The integration of biological models with genomic models is expected to have a significant impact on genetic improvement for different environments in the swine industry."
To develop the model, the team will use in-depth data on feed intake, body weights and body composition on pigs from several lines from a commercial breeding company. The resulting model will be validated using this data to demonstrate its ability to improve prediction.
This project is being directed by Dekkers and will be co-directed by Serão and Andrea Doeschl-Wilson, reader and group leader of the Mathematical Modeling Group and Deputy Head of Genetics and Genomics Division of the Roslin Institute in Edinburgh. Other team members include Iowa State faculty Rohan Fernando, professor of animal breeding, Jayasooriya Ranga Appuhamy, assistant professor of animal nutrition, along with a post-doctoral fellow and a PhD student who will be appointed to help conduct the research. Another collaborator is Jaap van Milgen, senior researcher and deputy-head of the INRAe-Agrocampus West Research Unit and developer of the INRA-Porc growth nutrition model. Several industry partners are also involved to supply insight, provide access to data and help facilitate model validation.