Breeding strategies for optimum sustainable genetic progress in Canadian dairy cattle

Project Overview

The development of novel traits (e.g., feed efficiency, methane emission, etc.), new genotyping technologies (e.g., whole genome re-sequencing), and novel tools (e.g., machine learning, precision livestock data collection, artificial reproductive technologies, etc.) are advancing at an unprecedented rate. This research addressed the use of these new technologies to ensure sustainability, genetic diversity, and to further improve production efficiency.

What Did the Research Team Do?

Examined strategies for breed improvement: Researchers analyzed and compared the benefits of various strategies and novel tools for breed improvement.

Investigated the potential of novel phenotypes: Explored phenotypes, such as traits involving health, fertility, environmental efficiency, and animal activity.

Explored the impact of management strategies on reproduction: Investigated the potential use of calf health records in breeding programs and the effect of artificial reproductive technologies on fertility traits.

Examined pipelines for selection in dairy breeding programs: Particularly those for data collection via precision livestock tools like rumination or activity collars, calf feeding centres, or calf activity monitors.

What Did the Research Team Find?

• Developed a tool for looking at correlations between all genetically evaluated traits in Canadian Holsteins. https://cgil.shinyapps.io/correlations/ 
• The use of timed artificial insemination (AI) biases genetic evaluations of fertility traits in dairy cattle. Timed AI can mask cows’ fertility performance, resulting in an unfair comparison of treated animals and innately fertile animals. The industry needs a standardized way of recording breeding codes to correct the bias. 
• Current data on calf health suggests that an increasing number of farms are recording calf disease events (i.e., respiratory illness and diarrhea). Lactanet has taken over these results and will introduce calf health into the national breeding program by next year.

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