Symposium review: Building a better cow-The Australian experience and future perspectives

Area of Science:

• Animal Breeding and Genetics
• Genomic Selection
• Quantitative Genetics

Background:

• Genomic selection utilizes phenotypes from genotyped reference populations to develop breeding values.
• Australia has implemented genomic breeding values for feed efficiency (feed saved) since 2015 and heat tolerance since 2017.
• Feed saved is integrated into the national breeding objective, prioritizing profitability and farmer preferences.

Purpose of the Study:

• To discuss the application and future directions of genomic selection in Australian cattle breeding.
• To address the challenges of lower genomic reliabilities in novel traits.
• To explore strategies for improving genomic prediction and trait inclusion in breeding objectives.

Main Methods:

• Application of genomic selection for feed efficiency and heat tolerance traits.
• Analysis of genomic reliabilities for established and novel traits.
• Discussion of methods to improve genomic prediction, including sequence data and gene expression studies.
• Consideration of international data pooling and reference population maintenance.

Main Results:

• Genomic breeding values for feed saved and heat tolerance are established in Australia.
• Novel genomic information-only traits often exhibit reliabilities below 50%, compared to 60-75% for established traits.
• Improved genomic prediction methods and data integration are key to enhancing reliability.

Conclusions:

• Despite lower reliabilities, novel traits contributing to the overall breeding objective (e.g., profit) are valuable.
• Future advancements include incorporating animal health traits and utilizing automated data capture.
• Enhanced use of data through bull selection tools and personalized genetic trends can improve farm management and selection decisions.