Selection indices in Holstein cattle of various countries

Area of Science:

• Animal Breeding and Genetics
• Dairy Science
• Agricultural Economics

Background:

• National breeding programs utilize selection indices to rank bulls for genetic improvement.
• Global dairy industries face evolving demands for production, durability, and health traits.

Purpose of the Study:

• To compare national selection indices and top bull listings across fifteen countries in August 2003.
• To analyze the relative emphasis on production, durability, and health/reproduction components in dairy cattle breeding.

Main Methods:

• Data collected from 15 countries based on geographical representation, Interbull membership, and progeny testing program size.
• Selection indices were analyzed by grouping traits into production, durability, and health/reproduction components.
• Comparison of relative emphasis on these components and commonality of top-listed bulls across countries.

Main Results:

• Average emphasis across countries was 59.5% for production, 28% for durability, and 12.5% for health/reproduction.
• Significant variation existed in the emphasis placed on production among national indices.
• The Danish S-Index demonstrated a balanced approach with 34% production, 29% durability, and 37% health/reproduction.

Conclusions:

• Dairy cattle breeding goals show considerable international variation, particularly in the weighting of production traits.
• Broadening breeding objectives has led to reduced overlap in top bull rankings internationally.
• The Danish S-Index serves as an example of a more balanced breeding strategy across key performance areas.